diff --git a/.gitignore b/.gitignore
index 82adae3..e35e31e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1 @@
-customvet
\ No newline at end of file
+linters
diff --git a/README.md b/README.md
index 7ad40d9..0fb904f 100644
--- a/README.md
+++ b/README.md
@@ -16,6 +16,25 @@ file which fills up memory leader to a denial of service attack). Users are
encouraged to use alternative constructs such as making use of
[io.LimitReader](https://pkg.go.dev/io#LimitReader).
+slowg
+-----
+
+`slowg` is an analyzer that checks for inappropriate use of `Logger.With` from
+the `log/slog` (or `golang.org/x/exp/slog`) package.
+
+`Logger.With()` (and `Logger.WithGroup()` creates a new Logger containing the
+provided attributes. The parent logger is cloned when arguments are supplied,
+which is a relatively expensive operation which should not be used in hot code
+path.
+
+For example, slowg would report the following call:
+
+ log.With("key", val).Info("message")
+
+Which should be replaced with the following call:
+
+ log.Info("message", "key", val)
+
timeafter
---------
diff --git a/go.mod b/go.mod
index f5a3c2c..cdccea5 100644
--- a/go.mod
+++ b/go.mod
@@ -2,7 +2,10 @@ module github.com/cilium/linters
go 1.19
-require golang.org/x/tools v0.11.0
+require (
+ golang.org/x/exp v0.0.0-20230711023510-fffb14384f22
+ golang.org/x/tools v0.11.0
+)
require (
golang.org/x/mod v0.12.0 // indirect
diff --git a/go.sum b/go.sum
index bf1aa7a..fe4d1d7 100644
--- a/go.sum
+++ b/go.sum
@@ -1,3 +1,5 @@
+golang.org/x/exp v0.0.0-20230711023510-fffb14384f22 h1:FqrVOBQxQ8r/UwwXibI0KMolVhvFiGobSfdE33deHJM=
+golang.org/x/exp v0.0.0-20230711023510-fffb14384f22/go.mod h1:FXUEEKJgO7OQYeo8N01OfiKP8RXMtf6e8aTskBGqWdc=
golang.org/x/mod v0.12.0 h1:rmsUpXtvNzj340zd98LZ4KntptpfRHwpFOHG188oHXc=
golang.org/x/mod v0.12.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
golang.org/x/sync v0.3.0 h1:ftCYgMx6zT/asHUrPw8BLLscYtGznsLAnjq5RH9P66E=
diff --git a/ioreadall/io_readall.go b/ioreadall/io_readall.go
index bc0d55e..e838342 100644
--- a/ioreadall/io_readall.go
+++ b/ioreadall/io_readall.go
@@ -22,8 +22,9 @@ var ioReadAllPkgs = []string{"io", "ioutil"}
// Analyzer implements an analysis function that checks for the use of
// io.ReadAll.
var Analyzer = &analysis.Analyzer{
- Name: "readall",
+ Name: "ioreadall",
Doc: `check for "io.ReadAll" instances`,
+ URL: "https://github.com/cilium/linters/ioreadall",
Requires: []*analysis.Analyzer{inspect.Analyzer},
Run: run,
}
diff --git a/main.go b/main.go
index 30ef12c..3b18a07 100644
--- a/main.go
+++ b/main.go
@@ -6,11 +6,16 @@ package main
import (
"github.com/cilium/linters/ioreadall"
+ "github.com/cilium/linters/slowg"
"github.com/cilium/linters/timeafter"
"golang.org/x/tools/go/analysis/multichecker"
)
func main() {
- multichecker.Main(timeafter.Analyzer, ioreadall.Analyzer)
+ multichecker.Main(
+ ioreadall.Analyzer,
+ slowg.Analyzer,
+ timeafter.Analyzer,
+ )
}
diff --git a/slowg/doc.go b/slowg/doc.go
new file mode 100644
index 0000000..9a17267
--- /dev/null
+++ b/slowg/doc.go
@@ -0,0 +1,22 @@
+// SPDX-License-Identifier: Apache-2.0
+// Copyright Authors of Cilium
+
+// Package slowg defines an Analyzer that checks for inappropriate use of
+// Logger.With() from the log/slog package.
+//
+// # Analyzer slowg
+//
+// slowg: check for inappropriate use of Logger.With().
+//
+// The slowg checker looks for calls to Logger.With() from the log/slog
+// package. Logger.With() constructs a new Logger containing the provided
+// attributes. The parent logger is cloned when arguments are supplied, which
+// is a relatively expensive operation which should not be used in hot code path.
+// For example, slowg would report the following call:
+//
+// log.With("key", val).Info("message")
+//
+// And suggest to replace it with the following call:
+//
+// log.Info("message", "key", val)
+package slowg
diff --git a/slowg/slowg.go b/slowg/slowg.go
new file mode 100644
index 0000000..36f873b
--- /dev/null
+++ b/slowg/slowg.go
@@ -0,0 +1,114 @@
+// SPDX-License-Identifier: Apache-2.0
+// Copyright Authors of Cilium
+
+package slowg
+
+import (
+ "errors"
+ "go/ast"
+ "go/types"
+
+ _ "golang.org/x/exp/slog" // require the exp module for the unit tests
+ "golang.org/x/tools/go/analysis"
+ "golang.org/x/tools/go/analysis/passes/inspect"
+ "golang.org/x/tools/go/ast/inspector"
+ "golang.org/x/tools/go/types/typeutil"
+)
+
+// Analyzer implements an analysis function that checks for inappropriate use
+// of Logger.With.
+var Analyzer = &analysis.Analyzer{
+ Name: "slowg",
+ Doc: "check for inappropriate use of Logger.With()",
+ URL: "https://github.com/cilium/linters/slowg",
+ Requires: []*analysis.Analyzer{inspect.Analyzer},
+ Run: run,
+}
+
+func run(pass *analysis.Pass) (any, error) {
+ inspect, ok := pass.ResultOf[inspect.Analyzer].(*inspector.Inspector)
+ if !ok {
+ return nil, errors.New("require analyzer of type *inspector.Inspector")
+ }
+ nodeFilter := []ast.Node{
+ (*ast.SelectorExpr)(nil),
+ }
+ inspect.Preorder(nodeFilter, func(node ast.Node) {
+ sel, ok := node.(*ast.SelectorExpr)
+ if !ok {
+ return
+ }
+
+ if sel.Sel == nil {
+ return
+ }
+ call, ok := sel.X.(*ast.CallExpr)
+ if !ok {
+ return
+ }
+ fn := typeutil.StaticCallee(pass.TypesInfo, call)
+ if fn == nil {
+ // not a static call
+ return
+ }
+ if !isSlogPkg(fn) {
+ // not the log/slog or x/exp/slog package
+ return
+ }
+ if recvName(fn) != "Logger" {
+ // not a receiver of the Logger struct
+ return
+ }
+ switch fn.Name() {
+ case "With", "WithGroup":
+ default:
+ // not one of the call we need to care about
+ return
+ }
+ meth := sel.Sel.Name
+ if !isLogMethod(meth) {
+ // not a logging method (e.g. Info, DebugCtx, ...)
+ return
+ }
+ pass.ReportRangef(call, "call to %s on a newly instantiated Logger", meth)
+ })
+ return nil, nil
+}
+
+func isSlogPkg(fn *types.Func) bool {
+ switch fn.Pkg().Path() {
+ case "log/slog":
+ return true
+ case "golang.org/x/exp/slog":
+ return true
+ }
+ return false
+}
+
+func isLogMethod(s string) bool {
+ switch s {
+ case "Log", "LogAttrs",
+ "Debug", "Info", "Warn", "Error",
+ "DebugCtx", "InfoCtx", "WarnCtx", "ErrorCtx":
+ return true
+ }
+ return false
+}
+
+func recvName(fn *types.Func) string {
+ sig, ok := fn.Type().(*types.Signature)
+ if !ok {
+ return ""
+ }
+ recv := sig.Recv()
+ if recv != nil {
+ t := recv.Type()
+ if pt, ok := t.(*types.Pointer); ok {
+ t = pt.Elem()
+ }
+ if nt, ok := t.(*types.Named); ok {
+ return nt.Obj().Name()
+ }
+ }
+ return ""
+}
diff --git a/slowg/slowg_stdlib_test.go b/slowg/slowg_stdlib_test.go
new file mode 100644
index 0000000..8a1bcf7
--- /dev/null
+++ b/slowg/slowg_stdlib_test.go
@@ -0,0 +1,17 @@
+// SPDX-License-Identifier: Apache-2.0
+// Copyright Authors of Cilium
+
+//go:build go1.21
+
+package slowg
+
+import (
+ "testing"
+
+ "golang.org/x/tools/go/analysis/analysistest"
+)
+
+func TestStdlib(t *testing.T) {
+ testdata := analysistest.TestData()
+ analysistest.Run(t, testdata, Analyzer, "stdlib")
+}
diff --git a/slowg/slowg_xexp_test.go b/slowg/slowg_xexp_test.go
new file mode 100644
index 0000000..87b18fa
--- /dev/null
+++ b/slowg/slowg_xexp_test.go
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: Apache-2.0
+// Copyright Authors of Cilium
+
+package slowg
+
+import (
+ "testing"
+
+ "golang.org/x/tools/go/analysis/analysistest"
+)
+
+func TestExp(t *testing.T) {
+ testdata := analysistest.TestData()
+ analysistest.Run(t, testdata, Analyzer, "xexp")
+}
diff --git a/slowg/testdata/src/golang.org b/slowg/testdata/src/golang.org
new file mode 120000
index 0000000..957acda
--- /dev/null
+++ b/slowg/testdata/src/golang.org
@@ -0,0 +1 @@
+../../../vendor/golang.org
\ No newline at end of file
diff --git a/slowg/testdata/src/stdlib/stdlib.go b/slowg/testdata/src/stdlib/stdlib.go
new file mode 100644
index 0000000..06f3513
--- /dev/null
+++ b/slowg/testdata/src/stdlib/stdlib.go
@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: Apache-2.0
+// Copyright Authors of Cilium
+
+//go:build go1.21
+
+package stdlib
+
+import (
+ "io"
+ "log/slog"
+)
+
+func main() {
+ log := slog.New(slog.NewTextHandler(io.Discard, nil))
+
+ log.Debug("debug")
+ log.Info("info")
+ log.Warn("warn")
+ log.Error("error")
+ log.DebugCtx(nil, "debug")
+ log.InfoCtx(nil, "info")
+ log.WarnCtx(nil, "warn")
+ log.ErrorCtx(nil, "error")
+ log.Log(nil, slog.LevelInfo, "log")
+ log.LogAttrs(nil, slog.LevelInfo, "log")
+
+ // With
+ log.With("key", "val").Debug("debug") // want `call to Debug on a newly instantiated Logger`
+ log.With("key", "val").Info("info") // want `call to Info on a newly instantiated Logger`
+ log.With("key", "val").Warn("warn") // want `call to Warn on a newly instantiated Logger`
+ log.With("key", "val").Error("error") // want `call to Error on a newly instantiated Logger`
+ log.With("key", "val").DebugCtx(nil, "debug") // want `call to DebugCtx on a newly instantiated Logger`
+ log.With("key", "val").InfoCtx(nil, "info") // want `call to InfoCtx on a newly instantiated Logger`
+ log.With("key", "val").WarnCtx(nil, "warn") // want `call to WarnCtx on a newly instantiated Logger`
+ log.With("key", "val").ErrorCtx(nil, "error") // want `call to ErrorCtx on a newly instantiated Logger`
+ log.With("key", "val").Log(nil, slog.LevelInfo, "log") // want `call to Log on a newly instantiated Logger`
+ log.With("key", "val").LogAttrs(nil, slog.LevelInfo, "log") // want `call to LogAttrs on a newly instantiated Logger`
+
+ // WithGroup
+ log.WithGroup("group").Debug("debug") // want `call to Debug on a newly instantiated Logger`
+ log.WithGroup("group").Info("info") // want `call to Info on a newly instantiated Logger`
+ log.WithGroup("group").Warn("warn") // want `call to Warn on a newly instantiated Logger`
+ log.WithGroup("group").Error("error") // want `call to Error on a newly instantiated Logger`
+ log.WithGroup("group").DebugCtx(nil, "debug") // want `call to DebugCtx on a newly instantiated Logger`
+ log.WithGroup("group").InfoCtx(nil, "info") // want `call to InfoCtx on a newly instantiated Logger`
+ log.WithGroup("group").WarnCtx(nil, "warn") // want `call to WarnCtx on a newly instantiated Logger`
+ log.WithGroup("group").ErrorCtx(nil, "error") // want `call to ErrorCtx on a newly instantiated Logger`
+ log.WithGroup("group").Log(nil, slog.LevelInfo, "log") // want `call to Log on a newly instantiated Logger`
+ log.WithGroup("group").LogAttrs(nil, slog.LevelInfo, "log") // want `call to LogAttrs on a newly instantiated Logger`
+}
diff --git a/slowg/testdata/src/xexp/xexp.go b/slowg/testdata/src/xexp/xexp.go
new file mode 100644
index 0000000..0d1486a
--- /dev/null
+++ b/slowg/testdata/src/xexp/xexp.go
@@ -0,0 +1,49 @@
+// SPDX-License-Identifier: Apache-2.0
+// Copyright Authors of Cilium
+
+package xexp
+
+import (
+ "io"
+
+ "golang.org/x/exp/slog"
+)
+
+func main() {
+ log := slog.New(slog.NewTextHandler(io.Discard, nil))
+
+ log.Debug("debug")
+ log.Info("info")
+ log.Warn("warn")
+ log.Error("error")
+ log.DebugCtx(nil, "debug")
+ log.InfoCtx(nil, "info")
+ log.WarnCtx(nil, "warn")
+ log.ErrorCtx(nil, "error")
+ log.Log(nil, slog.LevelInfo, "log")
+ log.LogAttrs(nil, slog.LevelInfo, "log")
+
+ // With
+ log.With("key", "val").Debug("debug") // want `call to Debug on a newly instantiated Logger`
+ log.With("key", "val").Info("info") // want `call to Info on a newly instantiated Logger`
+ log.With("key", "val").Warn("warn") // want `call to Warn on a newly instantiated Logger`
+ log.With("key", "val").Error("error") // want `call to Error on a newly instantiated Logger`
+ log.With("key", "val").DebugCtx(nil, "debug") // want `call to DebugCtx on a newly instantiated Logger`
+ log.With("key", "val").InfoCtx(nil, "info") // want `call to InfoCtx on a newly instantiated Logger`
+ log.With("key", "val").WarnCtx(nil, "warn") // want `call to WarnCtx on a newly instantiated Logger`
+ log.With("key", "val").ErrorCtx(nil, "error") // want `call to ErrorCtx on a newly instantiated Logger`
+ log.With("key", "val").Log(nil, slog.LevelInfo, "log") // want `call to Log on a newly instantiated Logger`
+ log.With("key", "val").LogAttrs(nil, slog.LevelInfo, "log") // want `call to LogAttrs on a newly instantiated Logger`
+
+ // WithGroup
+ log.WithGroup("group").Debug("debug") // want `call to Debug on a newly instantiated Logger`
+ log.WithGroup("group").Info("info") // want `call to Info on a newly instantiated Logger`
+ log.WithGroup("group").Warn("warn") // want `call to Warn on a newly instantiated Logger`
+ log.WithGroup("group").Error("error") // want `call to Error on a newly instantiated Logger`
+ log.WithGroup("group").DebugCtx(nil, "debug") // want `call to DebugCtx on a newly instantiated Logger`
+ log.WithGroup("group").InfoCtx(nil, "info") // want `call to InfoCtx on a newly instantiated Logger`
+ log.WithGroup("group").WarnCtx(nil, "warn") // want `call to WarnCtx on a newly instantiated Logger`
+ log.WithGroup("group").ErrorCtx(nil, "error") // want `call to ErrorCtx on a newly instantiated Logger`
+ log.WithGroup("group").Log(nil, slog.LevelInfo, "log") // want `call to Log on a newly instantiated Logger`
+ log.WithGroup("group").LogAttrs(nil, slog.LevelInfo, "log") // want `call to LogAttrs on a newly instantiated Logger`
+}
diff --git a/timeafter/time_after.go b/timeafter/time_after.go
index c0d55ee..84964ea 100644
--- a/timeafter/time_after.go
+++ b/timeafter/time_after.go
@@ -23,6 +23,7 @@ const (
var Analyzer = &analysis.Analyzer{
Name: "timeafter",
Doc: `check for "time.After" instances in loops`,
+ URL: "https://github.com/cilium/linters/timeafter",
Requires: []*analysis.Analyzer{inspect.Analyzer},
Run: run,
}
diff --git a/vendor/golang.org/x/exp/LICENSE b/vendor/golang.org/x/exp/LICENSE
new file mode 100644
index 0000000..6a66aea
--- /dev/null
+++ b/vendor/golang.org/x/exp/LICENSE
@@ -0,0 +1,27 @@
+Copyright (c) 2009 The Go Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+ * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+ * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/vendor/golang.org/x/exp/PATENTS b/vendor/golang.org/x/exp/PATENTS
new file mode 100644
index 0000000..7330990
--- /dev/null
+++ b/vendor/golang.org/x/exp/PATENTS
@@ -0,0 +1,22 @@
+Additional IP Rights Grant (Patents)
+
+"This implementation" means the copyrightable works distributed by
+Google as part of the Go project.
+
+Google hereby grants to You a perpetual, worldwide, non-exclusive,
+no-charge, royalty-free, irrevocable (except as stated in this section)
+patent license to make, have made, use, offer to sell, sell, import,
+transfer and otherwise run, modify and propagate the contents of this
+implementation of Go, where such license applies only to those patent
+claims, both currently owned or controlled by Google and acquired in
+the future, licensable by Google that are necessarily infringed by this
+implementation of Go. This grant does not include claims that would be
+infringed only as a consequence of further modification of this
+implementation. If you or your agent or exclusive licensee institute or
+order or agree to the institution of patent litigation against any
+entity (including a cross-claim or counterclaim in a lawsuit) alleging
+that this implementation of Go or any code incorporated within this
+implementation of Go constitutes direct or contributory patent
+infringement, or inducement of patent infringement, then any patent
+rights granted to you under this License for this implementation of Go
+shall terminate as of the date such litigation is filed.
diff --git a/vendor/golang.org/x/exp/constraints/constraints.go b/vendor/golang.org/x/exp/constraints/constraints.go
new file mode 100644
index 0000000..2c033df
--- /dev/null
+++ b/vendor/golang.org/x/exp/constraints/constraints.go
@@ -0,0 +1,50 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package constraints defines a set of useful constraints to be used
+// with type parameters.
+package constraints
+
+// Signed is a constraint that permits any signed integer type.
+// If future releases of Go add new predeclared signed integer types,
+// this constraint will be modified to include them.
+type Signed interface {
+ ~int | ~int8 | ~int16 | ~int32 | ~int64
+}
+
+// Unsigned is a constraint that permits any unsigned integer type.
+// If future releases of Go add new predeclared unsigned integer types,
+// this constraint will be modified to include them.
+type Unsigned interface {
+ ~uint | ~uint8 | ~uint16 | ~uint32 | ~uint64 | ~uintptr
+}
+
+// Integer is a constraint that permits any integer type.
+// If future releases of Go add new predeclared integer types,
+// this constraint will be modified to include them.
+type Integer interface {
+ Signed | Unsigned
+}
+
+// Float is a constraint that permits any floating-point type.
+// If future releases of Go add new predeclared floating-point types,
+// this constraint will be modified to include them.
+type Float interface {
+ ~float32 | ~float64
+}
+
+// Complex is a constraint that permits any complex numeric type.
+// If future releases of Go add new predeclared complex numeric types,
+// this constraint will be modified to include them.
+type Complex interface {
+ ~complex64 | ~complex128
+}
+
+// Ordered is a constraint that permits any ordered type: any type
+// that supports the operators < <= >= >.
+// If future releases of Go add new ordered types,
+// this constraint will be modified to include them.
+type Ordered interface {
+ Integer | Float | ~string
+}
diff --git a/vendor/golang.org/x/exp/slices/slices.go b/vendor/golang.org/x/exp/slices/slices.go
new file mode 100644
index 0000000..2540bd6
--- /dev/null
+++ b/vendor/golang.org/x/exp/slices/slices.go
@@ -0,0 +1,258 @@
+// Copyright 2021 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package slices defines various functions useful with slices of any type.
+// Unless otherwise specified, these functions all apply to the elements
+// of a slice at index 0 <= i < len(s).
+//
+// Note that the less function in IsSortedFunc, SortFunc, SortStableFunc requires a
+// strict weak ordering (https://en.wikipedia.org/wiki/Weak_ordering#Strict_weak_orderings),
+// or the sorting may fail to sort correctly. A common case is when sorting slices of
+// floating-point numbers containing NaN values.
+package slices
+
+import "golang.org/x/exp/constraints"
+
+// Equal reports whether two slices are equal: the same length and all
+// elements equal. If the lengths are different, Equal returns false.
+// Otherwise, the elements are compared in increasing index order, and the
+// comparison stops at the first unequal pair.
+// Floating point NaNs are not considered equal.
+func Equal[E comparable](s1, s2 []E) bool {
+ if len(s1) != len(s2) {
+ return false
+ }
+ for i := range s1 {
+ if s1[i] != s2[i] {
+ return false
+ }
+ }
+ return true
+}
+
+// EqualFunc reports whether two slices are equal using a comparison
+// function on each pair of elements. If the lengths are different,
+// EqualFunc returns false. Otherwise, the elements are compared in
+// increasing index order, and the comparison stops at the first index
+// for which eq returns false.
+func EqualFunc[E1, E2 any](s1 []E1, s2 []E2, eq func(E1, E2) bool) bool {
+ if len(s1) != len(s2) {
+ return false
+ }
+ for i, v1 := range s1 {
+ v2 := s2[i]
+ if !eq(v1, v2) {
+ return false
+ }
+ }
+ return true
+}
+
+// Compare compares the elements of s1 and s2.
+// The elements are compared sequentially, starting at index 0,
+// until one element is not equal to the other.
+// The result of comparing the first non-matching elements is returned.
+// If both slices are equal until one of them ends, the shorter slice is
+// considered less than the longer one.
+// The result is 0 if s1 == s2, -1 if s1 < s2, and +1 if s1 > s2.
+// Comparisons involving floating point NaNs are ignored.
+func Compare[E constraints.Ordered](s1, s2 []E) int {
+ s2len := len(s2)
+ for i, v1 := range s1 {
+ if i >= s2len {
+ return +1
+ }
+ v2 := s2[i]
+ switch {
+ case v1 < v2:
+ return -1
+ case v1 > v2:
+ return +1
+ }
+ }
+ if len(s1) < s2len {
+ return -1
+ }
+ return 0
+}
+
+// CompareFunc is like Compare but uses a comparison function
+// on each pair of elements. The elements are compared in increasing
+// index order, and the comparisons stop after the first time cmp
+// returns non-zero.
+// The result is the first non-zero result of cmp; if cmp always
+// returns 0 the result is 0 if len(s1) == len(s2), -1 if len(s1) < len(s2),
+// and +1 if len(s1) > len(s2).
+func CompareFunc[E1, E2 any](s1 []E1, s2 []E2, cmp func(E1, E2) int) int {
+ s2len := len(s2)
+ for i, v1 := range s1 {
+ if i >= s2len {
+ return +1
+ }
+ v2 := s2[i]
+ if c := cmp(v1, v2); c != 0 {
+ return c
+ }
+ }
+ if len(s1) < s2len {
+ return -1
+ }
+ return 0
+}
+
+// Index returns the index of the first occurrence of v in s,
+// or -1 if not present.
+func Index[E comparable](s []E, v E) int {
+ for i := range s {
+ if v == s[i] {
+ return i
+ }
+ }
+ return -1
+}
+
+// IndexFunc returns the first index i satisfying f(s[i]),
+// or -1 if none do.
+func IndexFunc[E any](s []E, f func(E) bool) int {
+ for i := range s {
+ if f(s[i]) {
+ return i
+ }
+ }
+ return -1
+}
+
+// Contains reports whether v is present in s.
+func Contains[E comparable](s []E, v E) bool {
+ return Index(s, v) >= 0
+}
+
+// ContainsFunc reports whether at least one
+// element e of s satisfies f(e).
+func ContainsFunc[E any](s []E, f func(E) bool) bool {
+ return IndexFunc(s, f) >= 0
+}
+
+// Insert inserts the values v... into s at index i,
+// returning the modified slice.
+// In the returned slice r, r[i] == v[0].
+// Insert panics if i is out of range.
+// This function is O(len(s) + len(v)).
+func Insert[S ~[]E, E any](s S, i int, v ...E) S {
+ tot := len(s) + len(v)
+ if tot <= cap(s) {
+ s2 := s[:tot]
+ copy(s2[i+len(v):], s[i:])
+ copy(s2[i:], v)
+ return s2
+ }
+ s2 := make(S, tot)
+ copy(s2, s[:i])
+ copy(s2[i:], v)
+ copy(s2[i+len(v):], s[i:])
+ return s2
+}
+
+// Delete removes the elements s[i:j] from s, returning the modified slice.
+// Delete panics if s[i:j] is not a valid slice of s.
+// Delete modifies the contents of the slice s; it does not create a new slice.
+// Delete is O(len(s)-j), so if many items must be deleted, it is better to
+// make a single call deleting them all together than to delete one at a time.
+// Delete might not modify the elements s[len(s)-(j-i):len(s)]. If those
+// elements contain pointers you might consider zeroing those elements so that
+// objects they reference can be garbage collected.
+func Delete[S ~[]E, E any](s S, i, j int) S {
+ _ = s[i:j] // bounds check
+
+ return append(s[:i], s[j:]...)
+}
+
+// Replace replaces the elements s[i:j] by the given v, and returns the
+// modified slice. Replace panics if s[i:j] is not a valid slice of s.
+func Replace[S ~[]E, E any](s S, i, j int, v ...E) S {
+ _ = s[i:j] // verify that i:j is a valid subslice
+ tot := len(s[:i]) + len(v) + len(s[j:])
+ if tot <= cap(s) {
+ s2 := s[:tot]
+ copy(s2[i+len(v):], s[j:])
+ copy(s2[i:], v)
+ return s2
+ }
+ s2 := make(S, tot)
+ copy(s2, s[:i])
+ copy(s2[i:], v)
+ copy(s2[i+len(v):], s[j:])
+ return s2
+}
+
+// Clone returns a copy of the slice.
+// The elements are copied using assignment, so this is a shallow clone.
+func Clone[S ~[]E, E any](s S) S {
+ // Preserve nil in case it matters.
+ if s == nil {
+ return nil
+ }
+ return append(S([]E{}), s...)
+}
+
+// Compact replaces consecutive runs of equal elements with a single copy.
+// This is like the uniq command found on Unix.
+// Compact modifies the contents of the slice s; it does not create a new slice.
+// When Compact discards m elements in total, it might not modify the elements
+// s[len(s)-m:len(s)]. If those elements contain pointers you might consider
+// zeroing those elements so that objects they reference can be garbage collected.
+func Compact[S ~[]E, E comparable](s S) S {
+ if len(s) < 2 {
+ return s
+ }
+ i := 1
+ for k := 1; k < len(s); k++ {
+ if s[k] != s[k-1] {
+ if i != k {
+ s[i] = s[k]
+ }
+ i++
+ }
+ }
+ return s[:i]
+}
+
+// CompactFunc is like Compact but uses a comparison function.
+func CompactFunc[S ~[]E, E any](s S, eq func(E, E) bool) S {
+ if len(s) < 2 {
+ return s
+ }
+ i := 1
+ for k := 1; k < len(s); k++ {
+ if !eq(s[k], s[k-1]) {
+ if i != k {
+ s[i] = s[k]
+ }
+ i++
+ }
+ }
+ return s[:i]
+}
+
+// Grow increases the slice's capacity, if necessary, to guarantee space for
+// another n elements. After Grow(n), at least n elements can be appended
+// to the slice without another allocation. If n is negative or too large to
+// allocate the memory, Grow panics.
+func Grow[S ~[]E, E any](s S, n int) S {
+ if n < 0 {
+ panic("cannot be negative")
+ }
+ if n -= cap(s) - len(s); n > 0 {
+ // TODO(https://go.dev/issue/53888): Make using []E instead of S
+ // to workaround a compiler bug where the runtime.growslice optimization
+ // does not take effect. Revert when the compiler is fixed.
+ s = append([]E(s)[:cap(s)], make([]E, n)...)[:len(s)]
+ }
+ return s
+}
+
+// Clip removes unused capacity from the slice, returning s[:len(s):len(s)].
+func Clip[S ~[]E, E any](s S) S {
+ return s[:len(s):len(s)]
+}
diff --git a/vendor/golang.org/x/exp/slices/sort.go b/vendor/golang.org/x/exp/slices/sort.go
new file mode 100644
index 0000000..231b644
--- /dev/null
+++ b/vendor/golang.org/x/exp/slices/sort.go
@@ -0,0 +1,128 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package slices
+
+import (
+ "math/bits"
+
+ "golang.org/x/exp/constraints"
+)
+
+// Sort sorts a slice of any ordered type in ascending order.
+// Sort may fail to sort correctly when sorting slices of floating-point
+// numbers containing Not-a-number (NaN) values.
+// Use slices.SortFunc(x, func(a, b float64) bool {return a < b || (math.IsNaN(a) && !math.IsNaN(b))})
+// instead if the input may contain NaNs.
+func Sort[E constraints.Ordered](x []E) {
+ n := len(x)
+ pdqsortOrdered(x, 0, n, bits.Len(uint(n)))
+}
+
+// SortFunc sorts the slice x in ascending order as determined by the less function.
+// This sort is not guaranteed to be stable.
+//
+// SortFunc requires that less is a strict weak ordering.
+// See https://en.wikipedia.org/wiki/Weak_ordering#Strict_weak_orderings.
+func SortFunc[E any](x []E, less func(a, b E) bool) {
+ n := len(x)
+ pdqsortLessFunc(x, 0, n, bits.Len(uint(n)), less)
+}
+
+// SortStableFunc sorts the slice x while keeping the original order of equal
+// elements, using less to compare elements.
+func SortStableFunc[E any](x []E, less func(a, b E) bool) {
+ stableLessFunc(x, len(x), less)
+}
+
+// IsSorted reports whether x is sorted in ascending order.
+func IsSorted[E constraints.Ordered](x []E) bool {
+ for i := len(x) - 1; i > 0; i-- {
+ if x[i] < x[i-1] {
+ return false
+ }
+ }
+ return true
+}
+
+// IsSortedFunc reports whether x is sorted in ascending order, with less as the
+// comparison function.
+func IsSortedFunc[E any](x []E, less func(a, b E) bool) bool {
+ for i := len(x) - 1; i > 0; i-- {
+ if less(x[i], x[i-1]) {
+ return false
+ }
+ }
+ return true
+}
+
+// BinarySearch searches for target in a sorted slice and returns the position
+// where target is found, or the position where target would appear in the
+// sort order; it also returns a bool saying whether the target is really found
+// in the slice. The slice must be sorted in increasing order.
+func BinarySearch[E constraints.Ordered](x []E, target E) (int, bool) {
+ // Inlining is faster than calling BinarySearchFunc with a lambda.
+ n := len(x)
+ // Define x[-1] < target and x[n] >= target.
+ // Invariant: x[i-1] < target, x[j] >= target.
+ i, j := 0, n
+ for i < j {
+ h := int(uint(i+j) >> 1) // avoid overflow when computing h
+ // i ≤ h < j
+ if x[h] < target {
+ i = h + 1 // preserves x[i-1] < target
+ } else {
+ j = h // preserves x[j] >= target
+ }
+ }
+ // i == j, x[i-1] < target, and x[j] (= x[i]) >= target => answer is i.
+ return i, i < n && x[i] == target
+}
+
+// BinarySearchFunc works like BinarySearch, but uses a custom comparison
+// function. The slice must be sorted in increasing order, where "increasing"
+// is defined by cmp. cmp should return 0 if the slice element matches
+// the target, a negative number if the slice element precedes the target,
+// or a positive number if the slice element follows the target.
+// cmp must implement the same ordering as the slice, such that if
+// cmp(a, t) < 0 and cmp(b, t) >= 0, then a must precede b in the slice.
+func BinarySearchFunc[E, T any](x []E, target T, cmp func(E, T) int) (int, bool) {
+ n := len(x)
+ // Define cmp(x[-1], target) < 0 and cmp(x[n], target) >= 0 .
+ // Invariant: cmp(x[i - 1], target) < 0, cmp(x[j], target) >= 0.
+ i, j := 0, n
+ for i < j {
+ h := int(uint(i+j) >> 1) // avoid overflow when computing h
+ // i ≤ h < j
+ if cmp(x[h], target) < 0 {
+ i = h + 1 // preserves cmp(x[i - 1], target) < 0
+ } else {
+ j = h // preserves cmp(x[j], target) >= 0
+ }
+ }
+ // i == j, cmp(x[i-1], target) < 0, and cmp(x[j], target) (= cmp(x[i], target)) >= 0 => answer is i.
+ return i, i < n && cmp(x[i], target) == 0
+}
+
+type sortedHint int // hint for pdqsort when choosing the pivot
+
+const (
+ unknownHint sortedHint = iota
+ increasingHint
+ decreasingHint
+)
+
+// xorshift paper: https://www.jstatsoft.org/article/view/v008i14/xorshift.pdf
+type xorshift uint64
+
+func (r *xorshift) Next() uint64 {
+ *r ^= *r << 13
+ *r ^= *r >> 17
+ *r ^= *r << 5
+ return uint64(*r)
+}
+
+func nextPowerOfTwo(length int) uint {
+ return 1 << bits.Len(uint(length))
+}
diff --git a/vendor/golang.org/x/exp/slices/zsortfunc.go b/vendor/golang.org/x/exp/slices/zsortfunc.go
new file mode 100644
index 0000000..2a63247
--- /dev/null
+++ b/vendor/golang.org/x/exp/slices/zsortfunc.go
@@ -0,0 +1,479 @@
+// Code generated by gen_sort_variants.go; DO NOT EDIT.
+
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package slices
+
+// insertionSortLessFunc sorts data[a:b] using insertion sort.
+func insertionSortLessFunc[E any](data []E, a, b int, less func(a, b E) bool) {
+ for i := a + 1; i < b; i++ {
+ for j := i; j > a && less(data[j], data[j-1]); j-- {
+ data[j], data[j-1] = data[j-1], data[j]
+ }
+ }
+}
+
+// siftDownLessFunc implements the heap property on data[lo:hi].
+// first is an offset into the array where the root of the heap lies.
+func siftDownLessFunc[E any](data []E, lo, hi, first int, less func(a, b E) bool) {
+ root := lo
+ for {
+ child := 2*root + 1
+ if child >= hi {
+ break
+ }
+ if child+1 < hi && less(data[first+child], data[first+child+1]) {
+ child++
+ }
+ if !less(data[first+root], data[first+child]) {
+ return
+ }
+ data[first+root], data[first+child] = data[first+child], data[first+root]
+ root = child
+ }
+}
+
+func heapSortLessFunc[E any](data []E, a, b int, less func(a, b E) bool) {
+ first := a
+ lo := 0
+ hi := b - a
+
+ // Build heap with greatest element at top.
+ for i := (hi - 1) / 2; i >= 0; i-- {
+ siftDownLessFunc(data, i, hi, first, less)
+ }
+
+ // Pop elements, largest first, into end of data.
+ for i := hi - 1; i >= 0; i-- {
+ data[first], data[first+i] = data[first+i], data[first]
+ siftDownLessFunc(data, lo, i, first, less)
+ }
+}
+
+// pdqsortLessFunc sorts data[a:b].
+// The algorithm based on pattern-defeating quicksort(pdqsort), but without the optimizations from BlockQuicksort.
+// pdqsort paper: https://arxiv.org/pdf/2106.05123.pdf
+// C++ implementation: https://github.com/orlp/pdqsort
+// Rust implementation: https://docs.rs/pdqsort/latest/pdqsort/
+// limit is the number of allowed bad (very unbalanced) pivots before falling back to heapsort.
+func pdqsortLessFunc[E any](data []E, a, b, limit int, less func(a, b E) bool) {
+ const maxInsertion = 12
+
+ var (
+ wasBalanced = true // whether the last partitioning was reasonably balanced
+ wasPartitioned = true // whether the slice was already partitioned
+ )
+
+ for {
+ length := b - a
+
+ if length <= maxInsertion {
+ insertionSortLessFunc(data, a, b, less)
+ return
+ }
+
+ // Fall back to heapsort if too many bad choices were made.
+ if limit == 0 {
+ heapSortLessFunc(data, a, b, less)
+ return
+ }
+
+ // If the last partitioning was imbalanced, we need to breaking patterns.
+ if !wasBalanced {
+ breakPatternsLessFunc(data, a, b, less)
+ limit--
+ }
+
+ pivot, hint := choosePivotLessFunc(data, a, b, less)
+ if hint == decreasingHint {
+ reverseRangeLessFunc(data, a, b, less)
+ // The chosen pivot was pivot-a elements after the start of the array.
+ // After reversing it is pivot-a elements before the end of the array.
+ // The idea came from Rust's implementation.
+ pivot = (b - 1) - (pivot - a)
+ hint = increasingHint
+ }
+
+ // The slice is likely already sorted.
+ if wasBalanced && wasPartitioned && hint == increasingHint {
+ if partialInsertionSortLessFunc(data, a, b, less) {
+ return
+ }
+ }
+
+ // Probably the slice contains many duplicate elements, partition the slice into
+ // elements equal to and elements greater than the pivot.
+ if a > 0 && !less(data[a-1], data[pivot]) {
+ mid := partitionEqualLessFunc(data, a, b, pivot, less)
+ a = mid
+ continue
+ }
+
+ mid, alreadyPartitioned := partitionLessFunc(data, a, b, pivot, less)
+ wasPartitioned = alreadyPartitioned
+
+ leftLen, rightLen := mid-a, b-mid
+ balanceThreshold := length / 8
+ if leftLen < rightLen {
+ wasBalanced = leftLen >= balanceThreshold
+ pdqsortLessFunc(data, a, mid, limit, less)
+ a = mid + 1
+ } else {
+ wasBalanced = rightLen >= balanceThreshold
+ pdqsortLessFunc(data, mid+1, b, limit, less)
+ b = mid
+ }
+ }
+}
+
+// partitionLessFunc does one quicksort partition.
+// Let p = data[pivot]
+// Moves elements in data[a:b] around, so that data[i]
=p for inewpivot.
+// On return, data[newpivot] = p
+func partitionLessFunc[E any](data []E, a, b, pivot int, less func(a, b E) bool) (newpivot int, alreadyPartitioned bool) {
+ data[a], data[pivot] = data[pivot], data[a]
+ i, j := a+1, b-1 // i and j are inclusive of the elements remaining to be partitioned
+
+ for i <= j && less(data[i], data[a]) {
+ i++
+ }
+ for i <= j && !less(data[j], data[a]) {
+ j--
+ }
+ if i > j {
+ data[j], data[a] = data[a], data[j]
+ return j, true
+ }
+ data[i], data[j] = data[j], data[i]
+ i++
+ j--
+
+ for {
+ for i <= j && less(data[i], data[a]) {
+ i++
+ }
+ for i <= j && !less(data[j], data[a]) {
+ j--
+ }
+ if i > j {
+ break
+ }
+ data[i], data[j] = data[j], data[i]
+ i++
+ j--
+ }
+ data[j], data[a] = data[a], data[j]
+ return j, false
+}
+
+// partitionEqualLessFunc partitions data[a:b] into elements equal to data[pivot] followed by elements greater than data[pivot].
+// It assumed that data[a:b] does not contain elements smaller than the data[pivot].
+func partitionEqualLessFunc[E any](data []E, a, b, pivot int, less func(a, b E) bool) (newpivot int) {
+ data[a], data[pivot] = data[pivot], data[a]
+ i, j := a+1, b-1 // i and j are inclusive of the elements remaining to be partitioned
+
+ for {
+ for i <= j && !less(data[a], data[i]) {
+ i++
+ }
+ for i <= j && less(data[a], data[j]) {
+ j--
+ }
+ if i > j {
+ break
+ }
+ data[i], data[j] = data[j], data[i]
+ i++
+ j--
+ }
+ return i
+}
+
+// partialInsertionSortLessFunc partially sorts a slice, returns true if the slice is sorted at the end.
+func partialInsertionSortLessFunc[E any](data []E, a, b int, less func(a, b E) bool) bool {
+ const (
+ maxSteps = 5 // maximum number of adjacent out-of-order pairs that will get shifted
+ shortestShifting = 50 // don't shift any elements on short arrays
+ )
+ i := a + 1
+ for j := 0; j < maxSteps; j++ {
+ for i < b && !less(data[i], data[i-1]) {
+ i++
+ }
+
+ if i == b {
+ return true
+ }
+
+ if b-a < shortestShifting {
+ return false
+ }
+
+ data[i], data[i-1] = data[i-1], data[i]
+
+ // Shift the smaller one to the left.
+ if i-a >= 2 {
+ for j := i - 1; j >= 1; j-- {
+ if !less(data[j], data[j-1]) {
+ break
+ }
+ data[j], data[j-1] = data[j-1], data[j]
+ }
+ }
+ // Shift the greater one to the right.
+ if b-i >= 2 {
+ for j := i + 1; j < b; j++ {
+ if !less(data[j], data[j-1]) {
+ break
+ }
+ data[j], data[j-1] = data[j-1], data[j]
+ }
+ }
+ }
+ return false
+}
+
+// breakPatternsLessFunc scatters some elements around in an attempt to break some patterns
+// that might cause imbalanced partitions in quicksort.
+func breakPatternsLessFunc[E any](data []E, a, b int, less func(a, b E) bool) {
+ length := b - a
+ if length >= 8 {
+ random := xorshift(length)
+ modulus := nextPowerOfTwo(length)
+
+ for idx := a + (length/4)*2 - 1; idx <= a+(length/4)*2+1; idx++ {
+ other := int(uint(random.Next()) & (modulus - 1))
+ if other >= length {
+ other -= length
+ }
+ data[idx], data[a+other] = data[a+other], data[idx]
+ }
+ }
+}
+
+// choosePivotLessFunc chooses a pivot in data[a:b].
+//
+// [0,8): chooses a static pivot.
+// [8,shortestNinther): uses the simple median-of-three method.
+// [shortestNinther,∞): uses the Tukey ninther method.
+func choosePivotLessFunc[E any](data []E, a, b int, less func(a, b E) bool) (pivot int, hint sortedHint) {
+ const (
+ shortestNinther = 50
+ maxSwaps = 4 * 3
+ )
+
+ l := b - a
+
+ var (
+ swaps int
+ i = a + l/4*1
+ j = a + l/4*2
+ k = a + l/4*3
+ )
+
+ if l >= 8 {
+ if l >= shortestNinther {
+ // Tukey ninther method, the idea came from Rust's implementation.
+ i = medianAdjacentLessFunc(data, i, &swaps, less)
+ j = medianAdjacentLessFunc(data, j, &swaps, less)
+ k = medianAdjacentLessFunc(data, k, &swaps, less)
+ }
+ // Find the median among i, j, k and stores it into j.
+ j = medianLessFunc(data, i, j, k, &swaps, less)
+ }
+
+ switch swaps {
+ case 0:
+ return j, increasingHint
+ case maxSwaps:
+ return j, decreasingHint
+ default:
+ return j, unknownHint
+ }
+}
+
+// order2LessFunc returns x,y where data[x] <= data[y], where x,y=a,b or x,y=b,a.
+func order2LessFunc[E any](data []E, a, b int, swaps *int, less func(a, b E) bool) (int, int) {
+ if less(data[b], data[a]) {
+ *swaps++
+ return b, a
+ }
+ return a, b
+}
+
+// medianLessFunc returns x where data[x] is the median of data[a],data[b],data[c], where x is a, b, or c.
+func medianLessFunc[E any](data []E, a, b, c int, swaps *int, less func(a, b E) bool) int {
+ a, b = order2LessFunc(data, a, b, swaps, less)
+ b, c = order2LessFunc(data, b, c, swaps, less)
+ a, b = order2LessFunc(data, a, b, swaps, less)
+ return b
+}
+
+// medianAdjacentLessFunc finds the median of data[a - 1], data[a], data[a + 1] and stores the index into a.
+func medianAdjacentLessFunc[E any](data []E, a int, swaps *int, less func(a, b E) bool) int {
+ return medianLessFunc(data, a-1, a, a+1, swaps, less)
+}
+
+func reverseRangeLessFunc[E any](data []E, a, b int, less func(a, b E) bool) {
+ i := a
+ j := b - 1
+ for i < j {
+ data[i], data[j] = data[j], data[i]
+ i++
+ j--
+ }
+}
+
+func swapRangeLessFunc[E any](data []E, a, b, n int, less func(a, b E) bool) {
+ for i := 0; i < n; i++ {
+ data[a+i], data[b+i] = data[b+i], data[a+i]
+ }
+}
+
+func stableLessFunc[E any](data []E, n int, less func(a, b E) bool) {
+ blockSize := 20 // must be > 0
+ a, b := 0, blockSize
+ for b <= n {
+ insertionSortLessFunc(data, a, b, less)
+ a = b
+ b += blockSize
+ }
+ insertionSortLessFunc(data, a, n, less)
+
+ for blockSize < n {
+ a, b = 0, 2*blockSize
+ for b <= n {
+ symMergeLessFunc(data, a, a+blockSize, b, less)
+ a = b
+ b += 2 * blockSize
+ }
+ if m := a + blockSize; m < n {
+ symMergeLessFunc(data, a, m, n, less)
+ }
+ blockSize *= 2
+ }
+}
+
+// symMergeLessFunc merges the two sorted subsequences data[a:m] and data[m:b] using
+// the SymMerge algorithm from Pok-Son Kim and Arne Kutzner, "Stable Minimum
+// Storage Merging by Symmetric Comparisons", in Susanne Albers and Tomasz
+// Radzik, editors, Algorithms - ESA 2004, volume 3221 of Lecture Notes in
+// Computer Science, pages 714-723. Springer, 2004.
+//
+// Let M = m-a and N = b-n. Wolog M < N.
+// The recursion depth is bound by ceil(log(N+M)).
+// The algorithm needs O(M*log(N/M + 1)) calls to data.Less.
+// The algorithm needs O((M+N)*log(M)) calls to data.Swap.
+//
+// The paper gives O((M+N)*log(M)) as the number of assignments assuming a
+// rotation algorithm which uses O(M+N+gcd(M+N)) assignments. The argumentation
+// in the paper carries through for Swap operations, especially as the block
+// swapping rotate uses only O(M+N) Swaps.
+//
+// symMerge assumes non-degenerate arguments: a < m && m < b.
+// Having the caller check this condition eliminates many leaf recursion calls,
+// which improves performance.
+func symMergeLessFunc[E any](data []E, a, m, b int, less func(a, b E) bool) {
+ // Avoid unnecessary recursions of symMerge
+ // by direct insertion of data[a] into data[m:b]
+ // if data[a:m] only contains one element.
+ if m-a == 1 {
+ // Use binary search to find the lowest index i
+ // such that data[i] >= data[a] for m <= i < b.
+ // Exit the search loop with i == b in case no such index exists.
+ i := m
+ j := b
+ for i < j {
+ h := int(uint(i+j) >> 1)
+ if less(data[h], data[a]) {
+ i = h + 1
+ } else {
+ j = h
+ }
+ }
+ // Swap values until data[a] reaches the position before i.
+ for k := a; k < i-1; k++ {
+ data[k], data[k+1] = data[k+1], data[k]
+ }
+ return
+ }
+
+ // Avoid unnecessary recursions of symMerge
+ // by direct insertion of data[m] into data[a:m]
+ // if data[m:b] only contains one element.
+ if b-m == 1 {
+ // Use binary search to find the lowest index i
+ // such that data[i] > data[m] for a <= i < m.
+ // Exit the search loop with i == m in case no such index exists.
+ i := a
+ j := m
+ for i < j {
+ h := int(uint(i+j) >> 1)
+ if !less(data[m], data[h]) {
+ i = h + 1
+ } else {
+ j = h
+ }
+ }
+ // Swap values until data[m] reaches the position i.
+ for k := m; k > i; k-- {
+ data[k], data[k-1] = data[k-1], data[k]
+ }
+ return
+ }
+
+ mid := int(uint(a+b) >> 1)
+ n := mid + m
+ var start, r int
+ if m > mid {
+ start = n - b
+ r = mid
+ } else {
+ start = a
+ r = m
+ }
+ p := n - 1
+
+ for start < r {
+ c := int(uint(start+r) >> 1)
+ if !less(data[p-c], data[c]) {
+ start = c + 1
+ } else {
+ r = c
+ }
+ }
+
+ end := n - start
+ if start < m && m < end {
+ rotateLessFunc(data, start, m, end, less)
+ }
+ if a < start && start < mid {
+ symMergeLessFunc(data, a, start, mid, less)
+ }
+ if mid < end && end < b {
+ symMergeLessFunc(data, mid, end, b, less)
+ }
+}
+
+// rotateLessFunc rotates two consecutive blocks u = data[a:m] and v = data[m:b] in data:
+// Data of the form 'x u v y' is changed to 'x v u y'.
+// rotate performs at most b-a many calls to data.Swap,
+// and it assumes non-degenerate arguments: a < m && m < b.
+func rotateLessFunc[E any](data []E, a, m, b int, less func(a, b E) bool) {
+ i := m - a
+ j := b - m
+
+ for i != j {
+ if i > j {
+ swapRangeLessFunc(data, m-i, m, j, less)
+ i -= j
+ } else {
+ swapRangeLessFunc(data, m-i, m+j-i, i, less)
+ j -= i
+ }
+ }
+ // i == j
+ swapRangeLessFunc(data, m-i, m, i, less)
+}
diff --git a/vendor/golang.org/x/exp/slices/zsortordered.go b/vendor/golang.org/x/exp/slices/zsortordered.go
new file mode 100644
index 0000000..efaa1c8
--- /dev/null
+++ b/vendor/golang.org/x/exp/slices/zsortordered.go
@@ -0,0 +1,481 @@
+// Code generated by gen_sort_variants.go; DO NOT EDIT.
+
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package slices
+
+import "golang.org/x/exp/constraints"
+
+// insertionSortOrdered sorts data[a:b] using insertion sort.
+func insertionSortOrdered[E constraints.Ordered](data []E, a, b int) {
+ for i := a + 1; i < b; i++ {
+ for j := i; j > a && (data[j] < data[j-1]); j-- {
+ data[j], data[j-1] = data[j-1], data[j]
+ }
+ }
+}
+
+// siftDownOrdered implements the heap property on data[lo:hi].
+// first is an offset into the array where the root of the heap lies.
+func siftDownOrdered[E constraints.Ordered](data []E, lo, hi, first int) {
+ root := lo
+ for {
+ child := 2*root + 1
+ if child >= hi {
+ break
+ }
+ if child+1 < hi && (data[first+child] < data[first+child+1]) {
+ child++
+ }
+ if !(data[first+root] < data[first+child]) {
+ return
+ }
+ data[first+root], data[first+child] = data[first+child], data[first+root]
+ root = child
+ }
+}
+
+func heapSortOrdered[E constraints.Ordered](data []E, a, b int) {
+ first := a
+ lo := 0
+ hi := b - a
+
+ // Build heap with greatest element at top.
+ for i := (hi - 1) / 2; i >= 0; i-- {
+ siftDownOrdered(data, i, hi, first)
+ }
+
+ // Pop elements, largest first, into end of data.
+ for i := hi - 1; i >= 0; i-- {
+ data[first], data[first+i] = data[first+i], data[first]
+ siftDownOrdered(data, lo, i, first)
+ }
+}
+
+// pdqsortOrdered sorts data[a:b].
+// The algorithm based on pattern-defeating quicksort(pdqsort), but without the optimizations from BlockQuicksort.
+// pdqsort paper: https://arxiv.org/pdf/2106.05123.pdf
+// C++ implementation: https://github.com/orlp/pdqsort
+// Rust implementation: https://docs.rs/pdqsort/latest/pdqsort/
+// limit is the number of allowed bad (very unbalanced) pivots before falling back to heapsort.
+func pdqsortOrdered[E constraints.Ordered](data []E, a, b, limit int) {
+ const maxInsertion = 12
+
+ var (
+ wasBalanced = true // whether the last partitioning was reasonably balanced
+ wasPartitioned = true // whether the slice was already partitioned
+ )
+
+ for {
+ length := b - a
+
+ if length <= maxInsertion {
+ insertionSortOrdered(data, a, b)
+ return
+ }
+
+ // Fall back to heapsort if too many bad choices were made.
+ if limit == 0 {
+ heapSortOrdered(data, a, b)
+ return
+ }
+
+ // If the last partitioning was imbalanced, we need to breaking patterns.
+ if !wasBalanced {
+ breakPatternsOrdered(data, a, b)
+ limit--
+ }
+
+ pivot, hint := choosePivotOrdered(data, a, b)
+ if hint == decreasingHint {
+ reverseRangeOrdered(data, a, b)
+ // The chosen pivot was pivot-a elements after the start of the array.
+ // After reversing it is pivot-a elements before the end of the array.
+ // The idea came from Rust's implementation.
+ pivot = (b - 1) - (pivot - a)
+ hint = increasingHint
+ }
+
+ // The slice is likely already sorted.
+ if wasBalanced && wasPartitioned && hint == increasingHint {
+ if partialInsertionSortOrdered(data, a, b) {
+ return
+ }
+ }
+
+ // Probably the slice contains many duplicate elements, partition the slice into
+ // elements equal to and elements greater than the pivot.
+ if a > 0 && !(data[a-1] < data[pivot]) {
+ mid := partitionEqualOrdered(data, a, b, pivot)
+ a = mid
+ continue
+ }
+
+ mid, alreadyPartitioned := partitionOrdered(data, a, b, pivot)
+ wasPartitioned = alreadyPartitioned
+
+ leftLen, rightLen := mid-a, b-mid
+ balanceThreshold := length / 8
+ if leftLen < rightLen {
+ wasBalanced = leftLen >= balanceThreshold
+ pdqsortOrdered(data, a, mid, limit)
+ a = mid + 1
+ } else {
+ wasBalanced = rightLen >= balanceThreshold
+ pdqsortOrdered(data, mid+1, b, limit)
+ b = mid
+ }
+ }
+}
+
+// partitionOrdered does one quicksort partition.
+// Let p = data[pivot]
+// Moves elements in data[a:b] around, so that data[i]=p for inewpivot.
+// On return, data[newpivot] = p
+func partitionOrdered[E constraints.Ordered](data []E, a, b, pivot int) (newpivot int, alreadyPartitioned bool) {
+ data[a], data[pivot] = data[pivot], data[a]
+ i, j := a+1, b-1 // i and j are inclusive of the elements remaining to be partitioned
+
+ for i <= j && (data[i] < data[a]) {
+ i++
+ }
+ for i <= j && !(data[j] < data[a]) {
+ j--
+ }
+ if i > j {
+ data[j], data[a] = data[a], data[j]
+ return j, true
+ }
+ data[i], data[j] = data[j], data[i]
+ i++
+ j--
+
+ for {
+ for i <= j && (data[i] < data[a]) {
+ i++
+ }
+ for i <= j && !(data[j] < data[a]) {
+ j--
+ }
+ if i > j {
+ break
+ }
+ data[i], data[j] = data[j], data[i]
+ i++
+ j--
+ }
+ data[j], data[a] = data[a], data[j]
+ return j, false
+}
+
+// partitionEqualOrdered partitions data[a:b] into elements equal to data[pivot] followed by elements greater than data[pivot].
+// It assumed that data[a:b] does not contain elements smaller than the data[pivot].
+func partitionEqualOrdered[E constraints.Ordered](data []E, a, b, pivot int) (newpivot int) {
+ data[a], data[pivot] = data[pivot], data[a]
+ i, j := a+1, b-1 // i and j are inclusive of the elements remaining to be partitioned
+
+ for {
+ for i <= j && !(data[a] < data[i]) {
+ i++
+ }
+ for i <= j && (data[a] < data[j]) {
+ j--
+ }
+ if i > j {
+ break
+ }
+ data[i], data[j] = data[j], data[i]
+ i++
+ j--
+ }
+ return i
+}
+
+// partialInsertionSortOrdered partially sorts a slice, returns true if the slice is sorted at the end.
+func partialInsertionSortOrdered[E constraints.Ordered](data []E, a, b int) bool {
+ const (
+ maxSteps = 5 // maximum number of adjacent out-of-order pairs that will get shifted
+ shortestShifting = 50 // don't shift any elements on short arrays
+ )
+ i := a + 1
+ for j := 0; j < maxSteps; j++ {
+ for i < b && !(data[i] < data[i-1]) {
+ i++
+ }
+
+ if i == b {
+ return true
+ }
+
+ if b-a < shortestShifting {
+ return false
+ }
+
+ data[i], data[i-1] = data[i-1], data[i]
+
+ // Shift the smaller one to the left.
+ if i-a >= 2 {
+ for j := i - 1; j >= 1; j-- {
+ if !(data[j] < data[j-1]) {
+ break
+ }
+ data[j], data[j-1] = data[j-1], data[j]
+ }
+ }
+ // Shift the greater one to the right.
+ if b-i >= 2 {
+ for j := i + 1; j < b; j++ {
+ if !(data[j] < data[j-1]) {
+ break
+ }
+ data[j], data[j-1] = data[j-1], data[j]
+ }
+ }
+ }
+ return false
+}
+
+// breakPatternsOrdered scatters some elements around in an attempt to break some patterns
+// that might cause imbalanced partitions in quicksort.
+func breakPatternsOrdered[E constraints.Ordered](data []E, a, b int) {
+ length := b - a
+ if length >= 8 {
+ random := xorshift(length)
+ modulus := nextPowerOfTwo(length)
+
+ for idx := a + (length/4)*2 - 1; idx <= a+(length/4)*2+1; idx++ {
+ other := int(uint(random.Next()) & (modulus - 1))
+ if other >= length {
+ other -= length
+ }
+ data[idx], data[a+other] = data[a+other], data[idx]
+ }
+ }
+}
+
+// choosePivotOrdered chooses a pivot in data[a:b].
+//
+// [0,8): chooses a static pivot.
+// [8,shortestNinther): uses the simple median-of-three method.
+// [shortestNinther,∞): uses the Tukey ninther method.
+func choosePivotOrdered[E constraints.Ordered](data []E, a, b int) (pivot int, hint sortedHint) {
+ const (
+ shortestNinther = 50
+ maxSwaps = 4 * 3
+ )
+
+ l := b - a
+
+ var (
+ swaps int
+ i = a + l/4*1
+ j = a + l/4*2
+ k = a + l/4*3
+ )
+
+ if l >= 8 {
+ if l >= shortestNinther {
+ // Tukey ninther method, the idea came from Rust's implementation.
+ i = medianAdjacentOrdered(data, i, &swaps)
+ j = medianAdjacentOrdered(data, j, &swaps)
+ k = medianAdjacentOrdered(data, k, &swaps)
+ }
+ // Find the median among i, j, k and stores it into j.
+ j = medianOrdered(data, i, j, k, &swaps)
+ }
+
+ switch swaps {
+ case 0:
+ return j, increasingHint
+ case maxSwaps:
+ return j, decreasingHint
+ default:
+ return j, unknownHint
+ }
+}
+
+// order2Ordered returns x,y where data[x] <= data[y], where x,y=a,b or x,y=b,a.
+func order2Ordered[E constraints.Ordered](data []E, a, b int, swaps *int) (int, int) {
+ if data[b] < data[a] {
+ *swaps++
+ return b, a
+ }
+ return a, b
+}
+
+// medianOrdered returns x where data[x] is the median of data[a],data[b],data[c], where x is a, b, or c.
+func medianOrdered[E constraints.Ordered](data []E, a, b, c int, swaps *int) int {
+ a, b = order2Ordered(data, a, b, swaps)
+ b, c = order2Ordered(data, b, c, swaps)
+ a, b = order2Ordered(data, a, b, swaps)
+ return b
+}
+
+// medianAdjacentOrdered finds the median of data[a - 1], data[a], data[a + 1] and stores the index into a.
+func medianAdjacentOrdered[E constraints.Ordered](data []E, a int, swaps *int) int {
+ return medianOrdered(data, a-1, a, a+1, swaps)
+}
+
+func reverseRangeOrdered[E constraints.Ordered](data []E, a, b int) {
+ i := a
+ j := b - 1
+ for i < j {
+ data[i], data[j] = data[j], data[i]
+ i++
+ j--
+ }
+}
+
+func swapRangeOrdered[E constraints.Ordered](data []E, a, b, n int) {
+ for i := 0; i < n; i++ {
+ data[a+i], data[b+i] = data[b+i], data[a+i]
+ }
+}
+
+func stableOrdered[E constraints.Ordered](data []E, n int) {
+ blockSize := 20 // must be > 0
+ a, b := 0, blockSize
+ for b <= n {
+ insertionSortOrdered(data, a, b)
+ a = b
+ b += blockSize
+ }
+ insertionSortOrdered(data, a, n)
+
+ for blockSize < n {
+ a, b = 0, 2*blockSize
+ for b <= n {
+ symMergeOrdered(data, a, a+blockSize, b)
+ a = b
+ b += 2 * blockSize
+ }
+ if m := a + blockSize; m < n {
+ symMergeOrdered(data, a, m, n)
+ }
+ blockSize *= 2
+ }
+}
+
+// symMergeOrdered merges the two sorted subsequences data[a:m] and data[m:b] using
+// the SymMerge algorithm from Pok-Son Kim and Arne Kutzner, "Stable Minimum
+// Storage Merging by Symmetric Comparisons", in Susanne Albers and Tomasz
+// Radzik, editors, Algorithms - ESA 2004, volume 3221 of Lecture Notes in
+// Computer Science, pages 714-723. Springer, 2004.
+//
+// Let M = m-a and N = b-n. Wolog M < N.
+// The recursion depth is bound by ceil(log(N+M)).
+// The algorithm needs O(M*log(N/M + 1)) calls to data.Less.
+// The algorithm needs O((M+N)*log(M)) calls to data.Swap.
+//
+// The paper gives O((M+N)*log(M)) as the number of assignments assuming a
+// rotation algorithm which uses O(M+N+gcd(M+N)) assignments. The argumentation
+// in the paper carries through for Swap operations, especially as the block
+// swapping rotate uses only O(M+N) Swaps.
+//
+// symMerge assumes non-degenerate arguments: a < m && m < b.
+// Having the caller check this condition eliminates many leaf recursion calls,
+// which improves performance.
+func symMergeOrdered[E constraints.Ordered](data []E, a, m, b int) {
+ // Avoid unnecessary recursions of symMerge
+ // by direct insertion of data[a] into data[m:b]
+ // if data[a:m] only contains one element.
+ if m-a == 1 {
+ // Use binary search to find the lowest index i
+ // such that data[i] >= data[a] for m <= i < b.
+ // Exit the search loop with i == b in case no such index exists.
+ i := m
+ j := b
+ for i < j {
+ h := int(uint(i+j) >> 1)
+ if data[h] < data[a] {
+ i = h + 1
+ } else {
+ j = h
+ }
+ }
+ // Swap values until data[a] reaches the position before i.
+ for k := a; k < i-1; k++ {
+ data[k], data[k+1] = data[k+1], data[k]
+ }
+ return
+ }
+
+ // Avoid unnecessary recursions of symMerge
+ // by direct insertion of data[m] into data[a:m]
+ // if data[m:b] only contains one element.
+ if b-m == 1 {
+ // Use binary search to find the lowest index i
+ // such that data[i] > data[m] for a <= i < m.
+ // Exit the search loop with i == m in case no such index exists.
+ i := a
+ j := m
+ for i < j {
+ h := int(uint(i+j) >> 1)
+ if !(data[m] < data[h]) {
+ i = h + 1
+ } else {
+ j = h
+ }
+ }
+ // Swap values until data[m] reaches the position i.
+ for k := m; k > i; k-- {
+ data[k], data[k-1] = data[k-1], data[k]
+ }
+ return
+ }
+
+ mid := int(uint(a+b) >> 1)
+ n := mid + m
+ var start, r int
+ if m > mid {
+ start = n - b
+ r = mid
+ } else {
+ start = a
+ r = m
+ }
+ p := n - 1
+
+ for start < r {
+ c := int(uint(start+r) >> 1)
+ if !(data[p-c] < data[c]) {
+ start = c + 1
+ } else {
+ r = c
+ }
+ }
+
+ end := n - start
+ if start < m && m < end {
+ rotateOrdered(data, start, m, end)
+ }
+ if a < start && start < mid {
+ symMergeOrdered(data, a, start, mid)
+ }
+ if mid < end && end < b {
+ symMergeOrdered(data, mid, end, b)
+ }
+}
+
+// rotateOrdered rotates two consecutive blocks u = data[a:m] and v = data[m:b] in data:
+// Data of the form 'x u v y' is changed to 'x v u y'.
+// rotate performs at most b-a many calls to data.Swap,
+// and it assumes non-degenerate arguments: a < m && m < b.
+func rotateOrdered[E constraints.Ordered](data []E, a, m, b int) {
+ i := m - a
+ j := b - m
+
+ for i != j {
+ if i > j {
+ swapRangeOrdered(data, m-i, m, j)
+ i -= j
+ } else {
+ swapRangeOrdered(data, m-i, m+j-i, i)
+ j -= i
+ }
+ }
+ // i == j
+ swapRangeOrdered(data, m-i, m, i)
+}
diff --git a/vendor/golang.org/x/exp/slog/attr.go b/vendor/golang.org/x/exp/slog/attr.go
new file mode 100644
index 0000000..a180d0e
--- /dev/null
+++ b/vendor/golang.org/x/exp/slog/attr.go
@@ -0,0 +1,102 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package slog
+
+import (
+ "fmt"
+ "time"
+)
+
+// An Attr is a key-value pair.
+type Attr struct {
+ Key string
+ Value Value
+}
+
+// String returns an Attr for a string value.
+func String(key, value string) Attr {
+ return Attr{key, StringValue(value)}
+}
+
+// Int64 returns an Attr for an int64.
+func Int64(key string, value int64) Attr {
+ return Attr{key, Int64Value(value)}
+}
+
+// Int converts an int to an int64 and returns
+// an Attr with that value.
+func Int(key string, value int) Attr {
+ return Int64(key, int64(value))
+}
+
+// Uint64 returns an Attr for a uint64.
+func Uint64(key string, v uint64) Attr {
+ return Attr{key, Uint64Value(v)}
+}
+
+// Float64 returns an Attr for a floating-point number.
+func Float64(key string, v float64) Attr {
+ return Attr{key, Float64Value(v)}
+}
+
+// Bool returns an Attr for a bool.
+func Bool(key string, v bool) Attr {
+ return Attr{key, BoolValue(v)}
+}
+
+// Time returns an Attr for a time.Time.
+// It discards the monotonic portion.
+func Time(key string, v time.Time) Attr {
+ return Attr{key, TimeValue(v)}
+}
+
+// Duration returns an Attr for a time.Duration.
+func Duration(key string, v time.Duration) Attr {
+ return Attr{key, DurationValue(v)}
+}
+
+// Group returns an Attr for a Group Value.
+// The first argument is the key; the remaining arguments
+// are converted to Attrs as in [Logger.Log].
+//
+// Use Group to collect several key-value pairs under a single
+// key on a log line, or as the result of LogValue
+// in order to log a single value as multiple Attrs.
+func Group(key string, args ...any) Attr {
+ return Attr{key, GroupValue(argsToAttrSlice(args)...)}
+}
+
+func argsToAttrSlice(args []any) []Attr {
+ var (
+ attr Attr
+ attrs []Attr
+ )
+ for len(args) > 0 {
+ attr, args = argsToAttr(args)
+ attrs = append(attrs, attr)
+ }
+ return attrs
+}
+
+// Any returns an Attr for the supplied value.
+// See [Value.AnyValue] for how values are treated.
+func Any(key string, value any) Attr {
+ return Attr{key, AnyValue(value)}
+}
+
+// Equal reports whether a and b have equal keys and values.
+func (a Attr) Equal(b Attr) bool {
+ return a.Key == b.Key && a.Value.Equal(b.Value)
+}
+
+func (a Attr) String() string {
+ return fmt.Sprintf("%s=%s", a.Key, a.Value)
+}
+
+// isEmpty reports whether a has an empty key and a nil value.
+// That can be written as Attr{} or Any("", nil).
+func (a Attr) isEmpty() bool {
+ return a.Key == "" && a.Value.num == 0 && a.Value.any == nil
+}
diff --git a/vendor/golang.org/x/exp/slog/doc.go b/vendor/golang.org/x/exp/slog/doc.go
new file mode 100644
index 0000000..3b24259
--- /dev/null
+++ b/vendor/golang.org/x/exp/slog/doc.go
@@ -0,0 +1,316 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+/*
+Package slog provides structured logging,
+in which log records include a message,
+a severity level, and various other attributes
+expressed as key-value pairs.
+
+It defines a type, [Logger],
+which provides several methods (such as [Logger.Info] and [Logger.Error])
+for reporting events of interest.
+
+Each Logger is associated with a [Handler].
+A Logger output method creates a [Record] from the method arguments
+and passes it to the Handler, which decides how to handle it.
+There is a default Logger accessible through top-level functions
+(such as [Info] and [Error]) that call the corresponding Logger methods.
+
+A log record consists of a time, a level, a message, and a set of key-value
+pairs, where the keys are strings and the values may be of any type.
+As an example,
+
+ slog.Info("hello", "count", 3)
+
+creates a record containing the time of the call,
+a level of Info, the message "hello", and a single
+pair with key "count" and value 3.
+
+The [Info] top-level function calls the [Logger.Info] method on the default Logger.
+In addition to [Logger.Info], there are methods for Debug, Warn and Error levels.
+Besides these convenience methods for common levels,
+there is also a [Logger.Log] method which takes the level as an argument.
+Each of these methods has a corresponding top-level function that uses the
+default logger.
+
+The default handler formats the log record's message, time, level, and attributes
+as a string and passes it to the [log] package.
+
+ 2022/11/08 15:28:26 INFO hello count=3
+
+For more control over the output format, create a logger with a different handler.
+This statement uses [New] to create a new logger with a TextHandler
+that writes structured records in text form to standard error:
+
+ logger := slog.New(slog.NewTextHandler(os.Stderr, nil))
+
+[TextHandler] output is a sequence of key=value pairs, easily and unambiguously
+parsed by machine. This statement:
+
+ logger.Info("hello", "count", 3)
+
+produces this output:
+
+ time=2022-11-08T15:28:26.000-05:00 level=INFO msg=hello count=3
+
+The package also provides [JSONHandler], whose output is line-delimited JSON:
+
+ logger := slog.New(slog.NewJSONHandler(os.Stdout, nil))
+ logger.Info("hello", "count", 3)
+
+produces this output:
+
+ {"time":"2022-11-08T15:28:26.000000000-05:00","level":"INFO","msg":"hello","count":3}
+
+Both [TextHandler] and [JSONHandler] can be configured with [HandlerOptions].
+There are options for setting the minimum level (see Levels, below),
+displaying the source file and line of the log call, and
+modifying attributes before they are logged.
+
+Setting a logger as the default with
+
+ slog.SetDefault(logger)
+
+will cause the top-level functions like [Info] to use it.
+[SetDefault] also updates the default logger used by the [log] package,
+so that existing applications that use [log.Printf] and related functions
+will send log records to the logger's handler without needing to be rewritten.
+
+Some attributes are common to many log calls.
+For example, you may wish to include the URL or trace identifier of a server request
+with all log events arising from the request.
+Rather than repeat the attribute with every log call, you can use [Logger.With]
+to construct a new Logger containing the attributes:
+
+ logger2 := logger.With("url", r.URL)
+
+The arguments to With are the same key-value pairs used in [Logger.Info].
+The result is a new Logger with the same handler as the original, but additional
+attributes that will appear in the output of every call.
+
+# Levels
+
+A [Level] is an integer representing the importance or severity of a log event.
+The higher the level, the more severe the event.
+This package defines constants for the most common levels,
+but any int can be used as a level.
+
+In an application, you may wish to log messages only at a certain level or greater.
+One common configuration is to log messages at Info or higher levels,
+suppressing debug logging until it is needed.
+The built-in handlers can be configured with the minimum level to output by
+setting [HandlerOptions.Level].
+The program's `main` function typically does this.
+The default value is LevelInfo.
+
+Setting the [HandlerOptions.Level] field to a [Level] value
+fixes the handler's minimum level throughout its lifetime.
+Setting it to a [LevelVar] allows the level to be varied dynamically.
+A LevelVar holds a Level and is safe to read or write from multiple
+goroutines.
+To vary the level dynamically for an entire program, first initialize
+a global LevelVar:
+
+ var programLevel = new(slog.LevelVar) // Info by default
+
+Then use the LevelVar to construct a handler, and make it the default:
+
+ h := slog.NewJSONHandler(os.Stderr, &slog.HandlerOptions{Level: programLevel})
+ slog.SetDefault(slog.New(h))
+
+Now the program can change its logging level with a single statement:
+
+ programLevel.Set(slog.LevelDebug)
+
+# Groups
+
+Attributes can be collected into groups.
+A group has a name that is used to qualify the names of its attributes.
+How this qualification is displayed depends on the handler.
+[TextHandler] separates the group and attribute names with a dot.
+[JSONHandler] treats each group as a separate JSON object, with the group name as the key.
+
+Use [Group] to create a Group attribute from a name and a list of key-value pairs:
+
+ slog.Group("request",
+ "method", r.Method,
+ "url", r.URL)
+
+TextHandler would display this group as
+
+ request.method=GET request.url=http://example.com
+
+JSONHandler would display it as
+
+ "request":{"method":"GET","url":"http://example.com"}
+
+Use [Logger.WithGroup] to qualify all of a Logger's output
+with a group name. Calling WithGroup on a Logger results in a
+new Logger with the same Handler as the original, but with all
+its attributes qualified by the group name.
+
+This can help prevent duplicate attribute keys in large systems,
+where subsystems might use the same keys.
+Pass each subsystem a different Logger with its own group name so that
+potential duplicates are qualified:
+
+ logger := slog.Default().With("id", systemID)
+ parserLogger := logger.WithGroup("parser")
+ parseInput(input, parserLogger)
+
+When parseInput logs with parserLogger, its keys will be qualified with "parser",
+so even if it uses the common key "id", the log line will have distinct keys.
+
+# Contexts
+
+Some handlers may wish to include information from the [context.Context] that is
+available at the call site. One example of such information
+is the identifier for the current span when tracing is enabled.
+
+The [Logger.Log] and [Logger.LogAttrs] methods take a context as a first
+argument, as do their corresponding top-level functions.
+
+Although the convenience methods on Logger (Info and so on) and the
+corresponding top-level functions do not take a context, the alternatives ending
+in "Ctx" do. For example,
+
+ slog.InfoCtx(ctx, "message")
+
+It is recommended to pass a context to an output method if one is available.
+
+# Attrs and Values
+
+An [Attr] is a key-value pair. The Logger output methods accept Attrs as well as
+alternating keys and values. The statement
+
+ slog.Info("hello", slog.Int("count", 3))
+
+behaves the same as
+
+ slog.Info("hello", "count", 3)
+
+There are convenience constructors for [Attr] such as [Int], [String], and [Bool]
+for common types, as well as the function [Any] for constructing Attrs of any
+type.
+
+The value part of an Attr is a type called [Value].
+Like an [any], a Value can hold any Go value,
+but it can represent typical values, including all numbers and strings,
+without an allocation.
+
+For the most efficient log output, use [Logger.LogAttrs].
+It is similar to [Logger.Log] but accepts only Attrs, not alternating
+keys and values; this allows it, too, to avoid allocation.
+
+The call
+
+ logger.LogAttrs(nil, slog.LevelInfo, "hello", slog.Int("count", 3))
+
+is the most efficient way to achieve the same output as
+
+ slog.Info("hello", "count", 3)
+
+# Customizing a type's logging behavior
+
+If a type implements the [LogValuer] interface, the [Value] returned from its LogValue
+method is used for logging. You can use this to control how values of the type
+appear in logs. For example, you can redact secret information like passwords,
+or gather a struct's fields in a Group. See the examples under [LogValuer] for
+details.
+
+A LogValue method may return a Value that itself implements [LogValuer]. The [Value.Resolve]
+method handles these cases carefully, avoiding infinite loops and unbounded recursion.
+Handler authors and others may wish to use Value.Resolve instead of calling LogValue directly.
+
+# Wrapping output methods
+
+The logger functions use reflection over the call stack to find the file name
+and line number of the logging call within the application. This can produce
+incorrect source information for functions that wrap slog. For instance, if you
+define this function in file mylog.go:
+
+ func Infof(format string, args ...any) {
+ slog.Default().Info(fmt.Sprintf(format, args...))
+ }
+
+and you call it like this in main.go:
+
+ Infof(slog.Default(), "hello, %s", "world")
+
+then slog will report the source file as mylog.go, not main.go.
+
+A correct implementation of Infof will obtain the source location
+(pc) and pass it to NewRecord.
+The Infof function in the package-level example called "wrapping"
+demonstrates how to do this.
+
+# Working with Records
+
+Sometimes a Handler will need to modify a Record
+before passing it on to another Handler or backend.
+A Record contains a mixture of simple public fields (e.g. Time, Level, Message)
+and hidden fields that refer to state (such as attributes) indirectly. This
+means that modifying a simple copy of a Record (e.g. by calling
+[Record.Add] or [Record.AddAttrs] to add attributes)
+may have unexpected effects on the original.
+Before modifying a Record, use [Clone] to
+create a copy that shares no state with the original,
+or create a new Record with [NewRecord]
+and build up its Attrs by traversing the old ones with [Record.Attrs].
+
+# Performance considerations
+
+If profiling your application demonstrates that logging is taking significant time,
+the following suggestions may help.
+
+If many log lines have a common attribute, use [Logger.With] to create a Logger with
+that attribute. The built-in handlers will format that attribute only once, at the
+call to [Logger.With]. The [Handler] interface is designed to allow that optimization,
+and a well-written Handler should take advantage of it.
+
+The arguments to a log call are always evaluated, even if the log event is discarded.
+If possible, defer computation so that it happens only if the value is actually logged.
+For example, consider the call
+
+ slog.Info("starting request", "url", r.URL.String()) // may compute String unnecessarily
+
+The URL.String method will be called even if the logger discards Info-level events.
+Instead, pass the URL directly:
+
+ slog.Info("starting request", "url", &r.URL) // calls URL.String only if needed
+
+The built-in [TextHandler] will call its String method, but only
+if the log event is enabled.
+Avoiding the call to String also preserves the structure of the underlying value.
+For example [JSONHandler] emits the components of the parsed URL as a JSON object.
+If you want to avoid eagerly paying the cost of the String call
+without causing the handler to potentially inspect the structure of the value,
+wrap the value in a fmt.Stringer implementation that hides its Marshal methods.
+
+You can also use the [LogValuer] interface to avoid unnecessary work in disabled log
+calls. Say you need to log some expensive value:
+
+ slog.Debug("frobbing", "value", computeExpensiveValue(arg))
+
+Even if this line is disabled, computeExpensiveValue will be called.
+To avoid that, define a type implementing LogValuer:
+
+ type expensive struct { arg int }
+
+ func (e expensive) LogValue() slog.Value {
+ return slog.AnyValue(computeExpensiveValue(e.arg))
+ }
+
+Then use a value of that type in log calls:
+
+ slog.Debug("frobbing", "value", expensive{arg})
+
+Now computeExpensiveValue will only be called when the line is enabled.
+
+The built-in handlers acquire a lock before calling [io.Writer.Write]
+to ensure that each record is written in one piece. User-defined
+handlers are responsible for their own locking.
+*/
+package slog
diff --git a/vendor/golang.org/x/exp/slog/handler.go b/vendor/golang.org/x/exp/slog/handler.go
new file mode 100644
index 0000000..74f8873
--- /dev/null
+++ b/vendor/golang.org/x/exp/slog/handler.go
@@ -0,0 +1,559 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package slog
+
+import (
+ "context"
+ "fmt"
+ "io"
+ "strconv"
+ "sync"
+ "time"
+
+ "golang.org/x/exp/slices"
+ "golang.org/x/exp/slog/internal/buffer"
+)
+
+// A Handler handles log records produced by a Logger..
+//
+// A typical handler may print log records to standard error,
+// or write them to a file or database, or perhaps augment them
+// with additional attributes and pass them on to another handler.
+//
+// Any of the Handler's methods may be called concurrently with itself
+// or with other methods. It is the responsibility of the Handler to
+// manage this concurrency.
+//
+// Users of the slog package should not invoke Handler methods directly.
+// They should use the methods of [Logger] instead.
+type Handler interface {
+ // Enabled reports whether the handler handles records at the given level.
+ // The handler ignores records whose level is lower.
+ // It is called early, before any arguments are processed,
+ // to save effort if the log event should be discarded.
+ // If called from a Logger method, the first argument is the context
+ // passed to that method, or context.Background() if nil was passed
+ // or the method does not take a context.
+ // The context is passed so Enabled can use its values
+ // to make a decision.
+ Enabled(context.Context, Level) bool
+
+ // Handle handles the Record.
+ // It will only be called when Enabled returns true.
+ // The Context argument is as for Enabled.
+ // It is present solely to provide Handlers access to the context's values.
+ // Canceling the context should not affect record processing.
+ // (Among other things, log messages may be necessary to debug a
+ // cancellation-related problem.)
+ //
+ // Handle methods that produce output should observe the following rules:
+ // - If r.Time is the zero time, ignore the time.
+ // - If r.PC is zero, ignore it.
+ // - Attr's values should be resolved.
+ // - If an Attr's key and value are both the zero value, ignore the Attr.
+ // This can be tested with attr.Equal(Attr{}).
+ // - If a group's key is empty, inline the group's Attrs.
+ // - If a group has no Attrs (even if it has a non-empty key),
+ // ignore it.
+ Handle(context.Context, Record) error
+
+ // WithAttrs returns a new Handler whose attributes consist of
+ // both the receiver's attributes and the arguments.
+ // The Handler owns the slice: it may retain, modify or discard it.
+ WithAttrs(attrs []Attr) Handler
+
+ // WithGroup returns a new Handler with the given group appended to
+ // the receiver's existing groups.
+ // The keys of all subsequent attributes, whether added by With or in a
+ // Record, should be qualified by the sequence of group names.
+ //
+ // How this qualification happens is up to the Handler, so long as
+ // this Handler's attribute keys differ from those of another Handler
+ // with a different sequence of group names.
+ //
+ // A Handler should treat WithGroup as starting a Group of Attrs that ends
+ // at the end of the log event. That is,
+ //
+ // logger.WithGroup("s").LogAttrs(level, msg, slog.Int("a", 1), slog.Int("b", 2))
+ //
+ // should behave like
+ //
+ // logger.LogAttrs(level, msg, slog.Group("s", slog.Int("a", 1), slog.Int("b", 2)))
+ //
+ // If the name is empty, WithGroup returns the receiver.
+ WithGroup(name string) Handler
+}
+
+type defaultHandler struct {
+ ch *commonHandler
+ // log.Output, except for testing
+ output func(calldepth int, message string) error
+}
+
+func newDefaultHandler(output func(int, string) error) *defaultHandler {
+ return &defaultHandler{
+ ch: &commonHandler{json: false},
+ output: output,
+ }
+}
+
+func (*defaultHandler) Enabled(_ context.Context, l Level) bool {
+ return l >= LevelInfo
+}
+
+// Collect the level, attributes and message in a string and
+// write it with the default log.Logger.
+// Let the log.Logger handle time and file/line.
+func (h *defaultHandler) Handle(ctx context.Context, r Record) error {
+ buf := buffer.New()
+ buf.WriteString(r.Level.String())
+ buf.WriteByte(' ')
+ buf.WriteString(r.Message)
+ state := h.ch.newHandleState(buf, true, " ", nil)
+ defer state.free()
+ state.appendNonBuiltIns(r)
+
+ // skip [h.output, defaultHandler.Handle, handlerWriter.Write, log.Output]
+ return h.output(4, buf.String())
+}
+
+func (h *defaultHandler) WithAttrs(as []Attr) Handler {
+ return &defaultHandler{h.ch.withAttrs(as), h.output}
+}
+
+func (h *defaultHandler) WithGroup(name string) Handler {
+ return &defaultHandler{h.ch.withGroup(name), h.output}
+}
+
+// HandlerOptions are options for a TextHandler or JSONHandler.
+// A zero HandlerOptions consists entirely of default values.
+type HandlerOptions struct {
+ // AddSource causes the handler to compute the source code position
+ // of the log statement and add a SourceKey attribute to the output.
+ AddSource bool
+
+ // Level reports the minimum record level that will be logged.
+ // The handler discards records with lower levels.
+ // If Level is nil, the handler assumes LevelInfo.
+ // The handler calls Level.Level for each record processed;
+ // to adjust the minimum level dynamically, use a LevelVar.
+ Level Leveler
+
+ // ReplaceAttr is called to rewrite each non-group attribute before it is logged.
+ // The attribute's value has been resolved (see [Value.Resolve]).
+ // If ReplaceAttr returns an Attr with Key == "", the attribute is discarded.
+ //
+ // The built-in attributes with keys "time", "level", "source", and "msg"
+ // are passed to this function, except that time is omitted
+ // if zero, and source is omitted if AddSource is false.
+ //
+ // The first argument is a list of currently open groups that contain the
+ // Attr. It must not be retained or modified. ReplaceAttr is never called
+ // for Group attributes, only their contents. For example, the attribute
+ // list
+ //
+ // Int("a", 1), Group("g", Int("b", 2)), Int("c", 3)
+ //
+ // results in consecutive calls to ReplaceAttr with the following arguments:
+ //
+ // nil, Int("a", 1)
+ // []string{"g"}, Int("b", 2)
+ // nil, Int("c", 3)
+ //
+ // ReplaceAttr can be used to change the default keys of the built-in
+ // attributes, convert types (for example, to replace a `time.Time` with the
+ // integer seconds since the Unix epoch), sanitize personal information, or
+ // remove attributes from the output.
+ ReplaceAttr func(groups []string, a Attr) Attr
+}
+
+// Keys for "built-in" attributes.
+const (
+ // TimeKey is the key used by the built-in handlers for the time
+ // when the log method is called. The associated Value is a [time.Time].
+ TimeKey = "time"
+ // LevelKey is the key used by the built-in handlers for the level
+ // of the log call. The associated value is a [Level].
+ LevelKey = "level"
+ // MessageKey is the key used by the built-in handlers for the
+ // message of the log call. The associated value is a string.
+ MessageKey = "msg"
+ // SourceKey is the key used by the built-in handlers for the source file
+ // and line of the log call. The associated value is a string.
+ SourceKey = "source"
+)
+
+type commonHandler struct {
+ json bool // true => output JSON; false => output text
+ opts HandlerOptions
+ preformattedAttrs []byte
+ groupPrefix string // for text: prefix of groups opened in preformatting
+ groups []string // all groups started from WithGroup
+ nOpenGroups int // the number of groups opened in preformattedAttrs
+ mu sync.Mutex
+ w io.Writer
+}
+
+func (h *commonHandler) clone() *commonHandler {
+ // We can't use assignment because we can't copy the mutex.
+ return &commonHandler{
+ json: h.json,
+ opts: h.opts,
+ preformattedAttrs: slices.Clip(h.preformattedAttrs),
+ groupPrefix: h.groupPrefix,
+ groups: slices.Clip(h.groups),
+ nOpenGroups: h.nOpenGroups,
+ w: h.w,
+ }
+}
+
+// enabled reports whether l is greater than or equal to the
+// minimum level.
+func (h *commonHandler) enabled(l Level) bool {
+ minLevel := LevelInfo
+ if h.opts.Level != nil {
+ minLevel = h.opts.Level.Level()
+ }
+ return l >= minLevel
+}
+
+func (h *commonHandler) withAttrs(as []Attr) *commonHandler {
+ h2 := h.clone()
+ // Pre-format the attributes as an optimization.
+ prefix := buffer.New()
+ defer prefix.Free()
+ prefix.WriteString(h.groupPrefix)
+ state := h2.newHandleState((*buffer.Buffer)(&h2.preformattedAttrs), false, "", prefix)
+ defer state.free()
+ if len(h2.preformattedAttrs) > 0 {
+ state.sep = h.attrSep()
+ }
+ state.openGroups()
+ for _, a := range as {
+ state.appendAttr(a)
+ }
+ // Remember the new prefix for later keys.
+ h2.groupPrefix = state.prefix.String()
+ // Remember how many opened groups are in preformattedAttrs,
+ // so we don't open them again when we handle a Record.
+ h2.nOpenGroups = len(h2.groups)
+ return h2
+}
+
+func (h *commonHandler) withGroup(name string) *commonHandler {
+ if name == "" {
+ return h
+ }
+ h2 := h.clone()
+ h2.groups = append(h2.groups, name)
+ return h2
+}
+
+func (h *commonHandler) handle(r Record) error {
+ state := h.newHandleState(buffer.New(), true, "", nil)
+ defer state.free()
+ if h.json {
+ state.buf.WriteByte('{')
+ }
+ // Built-in attributes. They are not in a group.
+ stateGroups := state.groups
+ state.groups = nil // So ReplaceAttrs sees no groups instead of the pre groups.
+ rep := h.opts.ReplaceAttr
+ // time
+ if !r.Time.IsZero() {
+ key := TimeKey
+ val := r.Time.Round(0) // strip monotonic to match Attr behavior
+ if rep == nil {
+ state.appendKey(key)
+ state.appendTime(val)
+ } else {
+ state.appendAttr(Time(key, val))
+ }
+ }
+ // level
+ key := LevelKey
+ val := r.Level
+ if rep == nil {
+ state.appendKey(key)
+ state.appendString(val.String())
+ } else {
+ state.appendAttr(Any(key, val))
+ }
+ // source
+ if h.opts.AddSource {
+ state.appendAttr(Any(SourceKey, r.source()))
+ }
+ key = MessageKey
+ msg := r.Message
+ if rep == nil {
+ state.appendKey(key)
+ state.appendString(msg)
+ } else {
+ state.appendAttr(String(key, msg))
+ }
+ state.groups = stateGroups // Restore groups passed to ReplaceAttrs.
+ state.appendNonBuiltIns(r)
+ state.buf.WriteByte('\n')
+
+ h.mu.Lock()
+ defer h.mu.Unlock()
+ _, err := h.w.Write(*state.buf)
+ return err
+}
+
+func (s *handleState) appendNonBuiltIns(r Record) {
+ // preformatted Attrs
+ if len(s.h.preformattedAttrs) > 0 {
+ s.buf.WriteString(s.sep)
+ s.buf.Write(s.h.preformattedAttrs)
+ s.sep = s.h.attrSep()
+ }
+ // Attrs in Record -- unlike the built-in ones, they are in groups started
+ // from WithGroup.
+ s.prefix = buffer.New()
+ defer s.prefix.Free()
+ s.prefix.WriteString(s.h.groupPrefix)
+ s.openGroups()
+ r.Attrs(func(a Attr) bool {
+ s.appendAttr(a)
+ return true
+ })
+ if s.h.json {
+ // Close all open groups.
+ for range s.h.groups {
+ s.buf.WriteByte('}')
+ }
+ // Close the top-level object.
+ s.buf.WriteByte('}')
+ }
+}
+
+// attrSep returns the separator between attributes.
+func (h *commonHandler) attrSep() string {
+ if h.json {
+ return ","
+ }
+ return " "
+}
+
+// handleState holds state for a single call to commonHandler.handle.
+// The initial value of sep determines whether to emit a separator
+// before the next key, after which it stays true.
+type handleState struct {
+ h *commonHandler
+ buf *buffer.Buffer
+ freeBuf bool // should buf be freed?
+ sep string // separator to write before next key
+ prefix *buffer.Buffer // for text: key prefix
+ groups *[]string // pool-allocated slice of active groups, for ReplaceAttr
+}
+
+var groupPool = sync.Pool{New: func() any {
+ s := make([]string, 0, 10)
+ return &s
+}}
+
+func (h *commonHandler) newHandleState(buf *buffer.Buffer, freeBuf bool, sep string, prefix *buffer.Buffer) handleState {
+ s := handleState{
+ h: h,
+ buf: buf,
+ freeBuf: freeBuf,
+ sep: sep,
+ prefix: prefix,
+ }
+ if h.opts.ReplaceAttr != nil {
+ s.groups = groupPool.Get().(*[]string)
+ *s.groups = append(*s.groups, h.groups[:h.nOpenGroups]...)
+ }
+ return s
+}
+
+func (s *handleState) free() {
+ if s.freeBuf {
+ s.buf.Free()
+ }
+ if gs := s.groups; gs != nil {
+ *gs = (*gs)[:0]
+ groupPool.Put(gs)
+ }
+}
+
+func (s *handleState) openGroups() {
+ for _, n := range s.h.groups[s.h.nOpenGroups:] {
+ s.openGroup(n)
+ }
+}
+
+// Separator for group names and keys.
+const keyComponentSep = '.'
+
+// openGroup starts a new group of attributes
+// with the given name.
+func (s *handleState) openGroup(name string) {
+ if s.h.json {
+ s.appendKey(name)
+ s.buf.WriteByte('{')
+ s.sep = ""
+ } else {
+ s.prefix.WriteString(name)
+ s.prefix.WriteByte(keyComponentSep)
+ }
+ // Collect group names for ReplaceAttr.
+ if s.groups != nil {
+ *s.groups = append(*s.groups, name)
+ }
+}
+
+// closeGroup ends the group with the given name.
+func (s *handleState) closeGroup(name string) {
+ if s.h.json {
+ s.buf.WriteByte('}')
+ } else {
+ (*s.prefix) = (*s.prefix)[:len(*s.prefix)-len(name)-1 /* for keyComponentSep */]
+ }
+ s.sep = s.h.attrSep()
+ if s.groups != nil {
+ *s.groups = (*s.groups)[:len(*s.groups)-1]
+ }
+}
+
+// appendAttr appends the Attr's key and value using app.
+// It handles replacement and checking for an empty key.
+// after replacement).
+func (s *handleState) appendAttr(a Attr) {
+ if rep := s.h.opts.ReplaceAttr; rep != nil && a.Value.Kind() != KindGroup {
+ var gs []string
+ if s.groups != nil {
+ gs = *s.groups
+ }
+ // Resolve before calling ReplaceAttr, so the user doesn't have to.
+ a.Value = a.Value.Resolve()
+ a = rep(gs, a)
+ }
+ a.Value = a.Value.Resolve()
+ // Elide empty Attrs.
+ if a.isEmpty() {
+ return
+ }
+ // Special case: Source.
+ if v := a.Value; v.Kind() == KindAny {
+ if src, ok := v.Any().(*Source); ok {
+ if s.h.json {
+ a.Value = src.group()
+ } else {
+ a.Value = StringValue(fmt.Sprintf("%s:%d", src.File, src.Line))
+ }
+ }
+ }
+ if a.Value.Kind() == KindGroup {
+ attrs := a.Value.Group()
+ // Output only non-empty groups.
+ if len(attrs) > 0 {
+ // Inline a group with an empty key.
+ if a.Key != "" {
+ s.openGroup(a.Key)
+ }
+ for _, aa := range attrs {
+ s.appendAttr(aa)
+ }
+ if a.Key != "" {
+ s.closeGroup(a.Key)
+ }
+ }
+ } else {
+ s.appendKey(a.Key)
+ s.appendValue(a.Value)
+ }
+}
+
+func (s *handleState) appendError(err error) {
+ s.appendString(fmt.Sprintf("!ERROR:%v", err))
+}
+
+func (s *handleState) appendKey(key string) {
+ s.buf.WriteString(s.sep)
+ if s.prefix != nil {
+ // TODO: optimize by avoiding allocation.
+ s.appendString(string(*s.prefix) + key)
+ } else {
+ s.appendString(key)
+ }
+ if s.h.json {
+ s.buf.WriteByte(':')
+ } else {
+ s.buf.WriteByte('=')
+ }
+ s.sep = s.h.attrSep()
+}
+
+func (s *handleState) appendString(str string) {
+ if s.h.json {
+ s.buf.WriteByte('"')
+ *s.buf = appendEscapedJSONString(*s.buf, str)
+ s.buf.WriteByte('"')
+ } else {
+ // text
+ if needsQuoting(str) {
+ *s.buf = strconv.AppendQuote(*s.buf, str)
+ } else {
+ s.buf.WriteString(str)
+ }
+ }
+}
+
+func (s *handleState) appendValue(v Value) {
+ var err error
+ if s.h.json {
+ err = appendJSONValue(s, v)
+ } else {
+ err = appendTextValue(s, v)
+ }
+ if err != nil {
+ s.appendError(err)
+ }
+}
+
+func (s *handleState) appendTime(t time.Time) {
+ if s.h.json {
+ appendJSONTime(s, t)
+ } else {
+ writeTimeRFC3339Millis(s.buf, t)
+ }
+}
+
+// This takes half the time of Time.AppendFormat.
+func writeTimeRFC3339Millis(buf *buffer.Buffer, t time.Time) {
+ year, month, day := t.Date()
+ buf.WritePosIntWidth(year, 4)
+ buf.WriteByte('-')
+ buf.WritePosIntWidth(int(month), 2)
+ buf.WriteByte('-')
+ buf.WritePosIntWidth(day, 2)
+ buf.WriteByte('T')
+ hour, min, sec := t.Clock()
+ buf.WritePosIntWidth(hour, 2)
+ buf.WriteByte(':')
+ buf.WritePosIntWidth(min, 2)
+ buf.WriteByte(':')
+ buf.WritePosIntWidth(sec, 2)
+ ns := t.Nanosecond()
+ buf.WriteByte('.')
+ buf.WritePosIntWidth(ns/1e6, 3)
+ _, offsetSeconds := t.Zone()
+ if offsetSeconds == 0 {
+ buf.WriteByte('Z')
+ } else {
+ offsetMinutes := offsetSeconds / 60
+ if offsetMinutes < 0 {
+ buf.WriteByte('-')
+ offsetMinutes = -offsetMinutes
+ } else {
+ buf.WriteByte('+')
+ }
+ buf.WritePosIntWidth(offsetMinutes/60, 2)
+ buf.WriteByte(':')
+ buf.WritePosIntWidth(offsetMinutes%60, 2)
+ }
+}
diff --git a/vendor/golang.org/x/exp/slog/internal/buffer/buffer.go b/vendor/golang.org/x/exp/slog/internal/buffer/buffer.go
new file mode 100644
index 0000000..7786c16
--- /dev/null
+++ b/vendor/golang.org/x/exp/slog/internal/buffer/buffer.go
@@ -0,0 +1,84 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package buffer provides a pool-allocated byte buffer.
+package buffer
+
+import (
+ "sync"
+)
+
+// Buffer adapted from go/src/fmt/print.go
+type Buffer []byte
+
+// Having an initial size gives a dramatic speedup.
+var bufPool = sync.Pool{
+ New: func() any {
+ b := make([]byte, 0, 1024)
+ return (*Buffer)(&b)
+ },
+}
+
+func New() *Buffer {
+ return bufPool.Get().(*Buffer)
+}
+
+func (b *Buffer) Free() {
+ // To reduce peak allocation, return only smaller buffers to the pool.
+ const maxBufferSize = 16 << 10
+ if cap(*b) <= maxBufferSize {
+ *b = (*b)[:0]
+ bufPool.Put(b)
+ }
+}
+
+func (b *Buffer) Reset() {
+ *b = (*b)[:0]
+}
+
+func (b *Buffer) Write(p []byte) (int, error) {
+ *b = append(*b, p...)
+ return len(p), nil
+}
+
+func (b *Buffer) WriteString(s string) {
+ *b = append(*b, s...)
+}
+
+func (b *Buffer) WriteByte(c byte) {
+ *b = append(*b, c)
+}
+
+func (b *Buffer) WritePosInt(i int) {
+ b.WritePosIntWidth(i, 0)
+}
+
+// WritePosIntWidth writes non-negative integer i to the buffer, padded on the left
+// by zeroes to the given width. Use a width of 0 to omit padding.
+func (b *Buffer) WritePosIntWidth(i, width int) {
+ // Cheap integer to fixed-width decimal ASCII.
+ // Copied from log/log.go.
+
+ if i < 0 {
+ panic("negative int")
+ }
+
+ // Assemble decimal in reverse order.
+ var bb [20]byte
+ bp := len(bb) - 1
+ for i >= 10 || width > 1 {
+ width--
+ q := i / 10
+ bb[bp] = byte('0' + i - q*10)
+ bp--
+ i = q
+ }
+ // i < 10
+ bb[bp] = byte('0' + i)
+ b.Write(bb[bp:])
+}
+
+func (b *Buffer) String() string {
+ return string(*b)
+}
diff --git a/vendor/golang.org/x/exp/slog/internal/ignorepc.go b/vendor/golang.org/x/exp/slog/internal/ignorepc.go
new file mode 100644
index 0000000..d125642
--- /dev/null
+++ b/vendor/golang.org/x/exp/slog/internal/ignorepc.go
@@ -0,0 +1,9 @@
+// Copyright 2023 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package internal
+
+// If IgnorePC is true, do not invoke runtime.Callers to get the pc.
+// This is solely for benchmarking the slowdown from runtime.Callers.
+var IgnorePC = false
diff --git a/vendor/golang.org/x/exp/slog/json_handler.go b/vendor/golang.org/x/exp/slog/json_handler.go
new file mode 100644
index 0000000..157ada8
--- /dev/null
+++ b/vendor/golang.org/x/exp/slog/json_handler.go
@@ -0,0 +1,336 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package slog
+
+import (
+ "bytes"
+ "context"
+ "encoding/json"
+ "errors"
+ "fmt"
+ "io"
+ "strconv"
+ "time"
+ "unicode/utf8"
+
+ "golang.org/x/exp/slog/internal/buffer"
+)
+
+// JSONHandler is a Handler that writes Records to an io.Writer as
+// line-delimited JSON objects.
+type JSONHandler struct {
+ *commonHandler
+}
+
+// NewJSONHandler creates a JSONHandler that writes to w,
+// using the given options.
+// If opts is nil, the default options are used.
+func NewJSONHandler(w io.Writer, opts *HandlerOptions) *JSONHandler {
+ if opts == nil {
+ opts = &HandlerOptions{}
+ }
+ return &JSONHandler{
+ &commonHandler{
+ json: true,
+ w: w,
+ opts: *opts,
+ },
+ }
+}
+
+// Enabled reports whether the handler handles records at the given level.
+// The handler ignores records whose level is lower.
+func (h *JSONHandler) Enabled(_ context.Context, level Level) bool {
+ return h.commonHandler.enabled(level)
+}
+
+// WithAttrs returns a new JSONHandler whose attributes consists
+// of h's attributes followed by attrs.
+func (h *JSONHandler) WithAttrs(attrs []Attr) Handler {
+ return &JSONHandler{commonHandler: h.commonHandler.withAttrs(attrs)}
+}
+
+func (h *JSONHandler) WithGroup(name string) Handler {
+ return &JSONHandler{commonHandler: h.commonHandler.withGroup(name)}
+}
+
+// Handle formats its argument Record as a JSON object on a single line.
+//
+// If the Record's time is zero, the time is omitted.
+// Otherwise, the key is "time"
+// and the value is output as with json.Marshal.
+//
+// If the Record's level is zero, the level is omitted.
+// Otherwise, the key is "level"
+// and the value of [Level.String] is output.
+//
+// If the AddSource option is set and source information is available,
+// the key is "source"
+// and the value is output as "FILE:LINE".
+//
+// The message's key is "msg".
+//
+// To modify these or other attributes, or remove them from the output, use
+// [HandlerOptions.ReplaceAttr].
+//
+// Values are formatted as with an [encoding/json.Encoder] with SetEscapeHTML(false),
+// with two exceptions.
+//
+// First, an Attr whose Value is of type error is formatted as a string, by
+// calling its Error method. Only errors in Attrs receive this special treatment,
+// not errors embedded in structs, slices, maps or other data structures that
+// are processed by the encoding/json package.
+//
+// Second, an encoding failure does not cause Handle to return an error.
+// Instead, the error message is formatted as a string.
+//
+// Each call to Handle results in a single serialized call to io.Writer.Write.
+func (h *JSONHandler) Handle(_ context.Context, r Record) error {
+ return h.commonHandler.handle(r)
+}
+
+// Adapted from time.Time.MarshalJSON to avoid allocation.
+func appendJSONTime(s *handleState, t time.Time) {
+ if y := t.Year(); y < 0 || y >= 10000 {
+ // RFC 3339 is clear that years are 4 digits exactly.
+ // See golang.org/issue/4556#c15 for more discussion.
+ s.appendError(errors.New("time.Time year outside of range [0,9999]"))
+ }
+ s.buf.WriteByte('"')
+ *s.buf = t.AppendFormat(*s.buf, time.RFC3339Nano)
+ s.buf.WriteByte('"')
+}
+
+func appendJSONValue(s *handleState, v Value) error {
+ switch v.Kind() {
+ case KindString:
+ s.appendString(v.str())
+ case KindInt64:
+ *s.buf = strconv.AppendInt(*s.buf, v.Int64(), 10)
+ case KindUint64:
+ *s.buf = strconv.AppendUint(*s.buf, v.Uint64(), 10)
+ case KindFloat64:
+ // json.Marshal is funny about floats; it doesn't
+ // always match strconv.AppendFloat. So just call it.
+ // That's expensive, but floats are rare.
+ if err := appendJSONMarshal(s.buf, v.Float64()); err != nil {
+ return err
+ }
+ case KindBool:
+ *s.buf = strconv.AppendBool(*s.buf, v.Bool())
+ case KindDuration:
+ // Do what json.Marshal does.
+ *s.buf = strconv.AppendInt(*s.buf, int64(v.Duration()), 10)
+ case KindTime:
+ s.appendTime(v.Time())
+ case KindAny:
+ a := v.Any()
+ _, jm := a.(json.Marshaler)
+ if err, ok := a.(error); ok && !jm {
+ s.appendString(err.Error())
+ } else {
+ return appendJSONMarshal(s.buf, a)
+ }
+ default:
+ panic(fmt.Sprintf("bad kind: %s", v.Kind()))
+ }
+ return nil
+}
+
+func appendJSONMarshal(buf *buffer.Buffer, v any) error {
+ // Use a json.Encoder to avoid escaping HTML.
+ var bb bytes.Buffer
+ enc := json.NewEncoder(&bb)
+ enc.SetEscapeHTML(false)
+ if err := enc.Encode(v); err != nil {
+ return err
+ }
+ bs := bb.Bytes()
+ buf.Write(bs[:len(bs)-1]) // remove final newline
+ return nil
+}
+
+// appendEscapedJSONString escapes s for JSON and appends it to buf.
+// It does not surround the string in quotation marks.
+//
+// Modified from encoding/json/encode.go:encodeState.string,
+// with escapeHTML set to false.
+func appendEscapedJSONString(buf []byte, s string) []byte {
+ char := func(b byte) { buf = append(buf, b) }
+ str := func(s string) { buf = append(buf, s...) }
+
+ start := 0
+ for i := 0; i < len(s); {
+ if b := s[i]; b < utf8.RuneSelf {
+ if safeSet[b] {
+ i++
+ continue
+ }
+ if start < i {
+ str(s[start:i])
+ }
+ char('\\')
+ switch b {
+ case '\\', '"':
+ char(b)
+ case '\n':
+ char('n')
+ case '\r':
+ char('r')
+ case '\t':
+ char('t')
+ default:
+ // This encodes bytes < 0x20 except for \t, \n and \r.
+ str(`u00`)
+ char(hex[b>>4])
+ char(hex[b&0xF])
+ }
+ i++
+ start = i
+ continue
+ }
+ c, size := utf8.DecodeRuneInString(s[i:])
+ if c == utf8.RuneError && size == 1 {
+ if start < i {
+ str(s[start:i])
+ }
+ str(`\ufffd`)
+ i += size
+ start = i
+ continue
+ }
+ // U+2028 is LINE SEPARATOR.
+ // U+2029 is PARAGRAPH SEPARATOR.
+ // They are both technically valid characters in JSON strings,
+ // but don't work in JSONP, which has to be evaluated as JavaScript,
+ // and can lead to security holes there. It is valid JSON to
+ // escape them, so we do so unconditionally.
+ // See http://timelessrepo.com/json-isnt-a-javascript-subset for discussion.
+ if c == '\u2028' || c == '\u2029' {
+ if start < i {
+ str(s[start:i])
+ }
+ str(`\u202`)
+ char(hex[c&0xF])
+ i += size
+ start = i
+ continue
+ }
+ i += size
+ }
+ if start < len(s) {
+ str(s[start:])
+ }
+ return buf
+}
+
+var hex = "0123456789abcdef"
+
+// Copied from encoding/json/tables.go.
+//
+// safeSet holds the value true if the ASCII character with the given array
+// position can be represented inside a JSON string without any further
+// escaping.
+//
+// All values are true except for the ASCII control characters (0-31), the
+// double quote ("), and the backslash character ("\").
+var safeSet = [utf8.RuneSelf]bool{
+ ' ': true,
+ '!': true,
+ '"': false,
+ '#': true,
+ '$': true,
+ '%': true,
+ '&': true,
+ '\'': true,
+ '(': true,
+ ')': true,
+ '*': true,
+ '+': true,
+ ',': true,
+ '-': true,
+ '.': true,
+ '/': true,
+ '0': true,
+ '1': true,
+ '2': true,
+ '3': true,
+ '4': true,
+ '5': true,
+ '6': true,
+ '7': true,
+ '8': true,
+ '9': true,
+ ':': true,
+ ';': true,
+ '<': true,
+ '=': true,
+ '>': true,
+ '?': true,
+ '@': true,
+ 'A': true,
+ 'B': true,
+ 'C': true,
+ 'D': true,
+ 'E': true,
+ 'F': true,
+ 'G': true,
+ 'H': true,
+ 'I': true,
+ 'J': true,
+ 'K': true,
+ 'L': true,
+ 'M': true,
+ 'N': true,
+ 'O': true,
+ 'P': true,
+ 'Q': true,
+ 'R': true,
+ 'S': true,
+ 'T': true,
+ 'U': true,
+ 'V': true,
+ 'W': true,
+ 'X': true,
+ 'Y': true,
+ 'Z': true,
+ '[': true,
+ '\\': false,
+ ']': true,
+ '^': true,
+ '_': true,
+ '`': true,
+ 'a': true,
+ 'b': true,
+ 'c': true,
+ 'd': true,
+ 'e': true,
+ 'f': true,
+ 'g': true,
+ 'h': true,
+ 'i': true,
+ 'j': true,
+ 'k': true,
+ 'l': true,
+ 'm': true,
+ 'n': true,
+ 'o': true,
+ 'p': true,
+ 'q': true,
+ 'r': true,
+ 's': true,
+ 't': true,
+ 'u': true,
+ 'v': true,
+ 'w': true,
+ 'x': true,
+ 'y': true,
+ 'z': true,
+ '{': true,
+ '|': true,
+ '}': true,
+ '~': true,
+ '\u007f': true,
+}
diff --git a/vendor/golang.org/x/exp/slog/level.go b/vendor/golang.org/x/exp/slog/level.go
new file mode 100644
index 0000000..b2365f0
--- /dev/null
+++ b/vendor/golang.org/x/exp/slog/level.go
@@ -0,0 +1,201 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package slog
+
+import (
+ "errors"
+ "fmt"
+ "strconv"
+ "strings"
+ "sync/atomic"
+)
+
+// A Level is the importance or severity of a log event.
+// The higher the level, the more important or severe the event.
+type Level int
+
+// Level numbers are inherently arbitrary,
+// but we picked them to satisfy three constraints.
+// Any system can map them to another numbering scheme if it wishes.
+//
+// First, we wanted the default level to be Info, Since Levels are ints, Info is
+// the default value for int, zero.
+//
+
+// Second, we wanted to make it easy to use levels to specify logger verbosity.
+// Since a larger level means a more severe event, a logger that accepts events
+// with smaller (or more negative) level means a more verbose logger. Logger
+// verbosity is thus the negation of event severity, and the default verbosity
+// of 0 accepts all events at least as severe as INFO.
+//
+// Third, we wanted some room between levels to accommodate schemes with named
+// levels between ours. For example, Google Cloud Logging defines a Notice level
+// between Info and Warn. Since there are only a few of these intermediate
+// levels, the gap between the numbers need not be large. Our gap of 4 matches
+// OpenTelemetry's mapping. Subtracting 9 from an OpenTelemetry level in the
+// DEBUG, INFO, WARN and ERROR ranges converts it to the corresponding slog
+// Level range. OpenTelemetry also has the names TRACE and FATAL, which slog
+// does not. But those OpenTelemetry levels can still be represented as slog
+// Levels by using the appropriate integers.
+//
+// Names for common levels.
+const (
+ LevelDebug Level = -4
+ LevelInfo Level = 0
+ LevelWarn Level = 4
+ LevelError Level = 8
+)
+
+// String returns a name for the level.
+// If the level has a name, then that name
+// in uppercase is returned.
+// If the level is between named values, then
+// an integer is appended to the uppercased name.
+// Examples:
+//
+// LevelWarn.String() => "WARN"
+// (LevelInfo+2).String() => "INFO+2"
+func (l Level) String() string {
+ str := func(base string, val Level) string {
+ if val == 0 {
+ return base
+ }
+ return fmt.Sprintf("%s%+d", base, val)
+ }
+
+ switch {
+ case l < LevelInfo:
+ return str("DEBUG", l-LevelDebug)
+ case l < LevelWarn:
+ return str("INFO", l-LevelInfo)
+ case l < LevelError:
+ return str("WARN", l-LevelWarn)
+ default:
+ return str("ERROR", l-LevelError)
+ }
+}
+
+// MarshalJSON implements [encoding/json.Marshaler]
+// by quoting the output of [Level.String].
+func (l Level) MarshalJSON() ([]byte, error) {
+ // AppendQuote is sufficient for JSON-encoding all Level strings.
+ // They don't contain any runes that would produce invalid JSON
+ // when escaped.
+ return strconv.AppendQuote(nil, l.String()), nil
+}
+
+// UnmarshalJSON implements [encoding/json.Unmarshaler]
+// It accepts any string produced by [Level.MarshalJSON],
+// ignoring case.
+// It also accepts numeric offsets that would result in a different string on
+// output. For example, "Error-8" would marshal as "INFO".
+func (l *Level) UnmarshalJSON(data []byte) error {
+ s, err := strconv.Unquote(string(data))
+ if err != nil {
+ return err
+ }
+ return l.parse(s)
+}
+
+// MarshalText implements [encoding.TextMarshaler]
+// by calling [Level.String].
+func (l Level) MarshalText() ([]byte, error) {
+ return []byte(l.String()), nil
+}
+
+// UnmarshalText implements [encoding.TextUnmarshaler].
+// It accepts any string produced by [Level.MarshalText],
+// ignoring case.
+// It also accepts numeric offsets that would result in a different string on
+// output. For example, "Error-8" would marshal as "INFO".
+func (l *Level) UnmarshalText(data []byte) error {
+ return l.parse(string(data))
+}
+
+func (l *Level) parse(s string) (err error) {
+ defer func() {
+ if err != nil {
+ err = fmt.Errorf("slog: level string %q: %w", s, err)
+ }
+ }()
+
+ name := s
+ offset := 0
+ if i := strings.IndexAny(s, "+-"); i >= 0 {
+ name = s[:i]
+ offset, err = strconv.Atoi(s[i:])
+ if err != nil {
+ return err
+ }
+ }
+ switch strings.ToUpper(name) {
+ case "DEBUG":
+ *l = LevelDebug
+ case "INFO":
+ *l = LevelInfo
+ case "WARN":
+ *l = LevelWarn
+ case "ERROR":
+ *l = LevelError
+ default:
+ return errors.New("unknown name")
+ }
+ *l += Level(offset)
+ return nil
+}
+
+// Level returns the receiver.
+// It implements Leveler.
+func (l Level) Level() Level { return l }
+
+// A LevelVar is a Level variable, to allow a Handler level to change
+// dynamically.
+// It implements Leveler as well as a Set method,
+// and it is safe for use by multiple goroutines.
+// The zero LevelVar corresponds to LevelInfo.
+type LevelVar struct {
+ val atomic.Int64
+}
+
+// Level returns v's level.
+func (v *LevelVar) Level() Level {
+ return Level(int(v.val.Load()))
+}
+
+// Set sets v's level to l.
+func (v *LevelVar) Set(l Level) {
+ v.val.Store(int64(l))
+}
+
+func (v *LevelVar) String() string {
+ return fmt.Sprintf("LevelVar(%s)", v.Level())
+}
+
+// MarshalText implements [encoding.TextMarshaler]
+// by calling [Level.MarshalText].
+func (v *LevelVar) MarshalText() ([]byte, error) {
+ return v.Level().MarshalText()
+}
+
+// UnmarshalText implements [encoding.TextUnmarshaler]
+// by calling [Level.UnmarshalText].
+func (v *LevelVar) UnmarshalText(data []byte) error {
+ var l Level
+ if err := l.UnmarshalText(data); err != nil {
+ return err
+ }
+ v.Set(l)
+ return nil
+}
+
+// A Leveler provides a Level value.
+//
+// As Level itself implements Leveler, clients typically supply
+// a Level value wherever a Leveler is needed, such as in HandlerOptions.
+// Clients who need to vary the level dynamically can provide a more complex
+// Leveler implementation such as *LevelVar.
+type Leveler interface {
+ Level() Level
+}
diff --git a/vendor/golang.org/x/exp/slog/logger.go b/vendor/golang.org/x/exp/slog/logger.go
new file mode 100644
index 0000000..6ad93bf
--- /dev/null
+++ b/vendor/golang.org/x/exp/slog/logger.go
@@ -0,0 +1,295 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package slog
+
+import (
+ "context"
+ "log"
+ "runtime"
+ "sync/atomic"
+ "time"
+
+ "golang.org/x/exp/slog/internal"
+)
+
+var defaultLogger atomic.Value
+
+func init() {
+ defaultLogger.Store(New(newDefaultHandler(log.Output)))
+}
+
+// Default returns the default Logger.
+func Default() *Logger { return defaultLogger.Load().(*Logger) }
+
+// SetDefault makes l the default Logger.
+// After this call, output from the log package's default Logger
+// (as with [log.Print], etc.) will be logged at LevelInfo using l's Handler.
+func SetDefault(l *Logger) {
+ defaultLogger.Store(l)
+ // If the default's handler is a defaultHandler, then don't use a handleWriter,
+ // or we'll deadlock as they both try to acquire the log default mutex.
+ // The defaultHandler will use whatever the log default writer is currently
+ // set to, which is correct.
+ // This can occur with SetDefault(Default()).
+ // See TestSetDefault.
+ if _, ok := l.Handler().(*defaultHandler); !ok {
+ capturePC := log.Flags()&(log.Lshortfile|log.Llongfile) != 0
+ log.SetOutput(&handlerWriter{l.Handler(), LevelInfo, capturePC})
+ log.SetFlags(0) // we want just the log message, no time or location
+ }
+}
+
+// handlerWriter is an io.Writer that calls a Handler.
+// It is used to link the default log.Logger to the default slog.Logger.
+type handlerWriter struct {
+ h Handler
+ level Level
+ capturePC bool
+}
+
+func (w *handlerWriter) Write(buf []byte) (int, error) {
+ if !w.h.Enabled(context.Background(), w.level) {
+ return 0, nil
+ }
+ var pc uintptr
+ if !internal.IgnorePC && w.capturePC {
+ // skip [runtime.Callers, w.Write, Logger.Output, log.Print]
+ var pcs [1]uintptr
+ runtime.Callers(4, pcs[:])
+ pc = pcs[0]
+ }
+
+ // Remove final newline.
+ origLen := len(buf) // Report that the entire buf was written.
+ if len(buf) > 0 && buf[len(buf)-1] == '\n' {
+ buf = buf[:len(buf)-1]
+ }
+ r := NewRecord(time.Now(), w.level, string(buf), pc)
+ return origLen, w.h.Handle(context.Background(), r)
+}
+
+// A Logger records structured information about each call to its
+// Log, Debug, Info, Warn, and Error methods.
+// For each call, it creates a Record and passes it to a Handler.
+//
+// To create a new Logger, call [New] or a Logger method
+// that begins "With".
+type Logger struct {
+ handler Handler // for structured logging
+}
+
+func (l *Logger) clone() *Logger {
+ c := *l
+ return &c
+}
+
+// Handler returns l's Handler.
+func (l *Logger) Handler() Handler { return l.handler }
+
+// With returns a new Logger that includes the given arguments, converted to
+// Attrs as in [Logger.Log].
+// The Attrs will be added to each output from the Logger.
+// The new Logger shares the old Logger's context.
+// The new Logger's handler is the result of calling WithAttrs on the receiver's
+// handler.
+func (l *Logger) With(args ...any) *Logger {
+ c := l.clone()
+ c.handler = l.handler.WithAttrs(argsToAttrSlice(args))
+ return c
+}
+
+// WithGroup returns a new Logger that starts a group. The keys of all
+// attributes added to the Logger will be qualified by the given name.
+// (How that qualification happens depends on the [Handler.WithGroup]
+// method of the Logger's Handler.)
+// The new Logger shares the old Logger's context.
+//
+// The new Logger's handler is the result of calling WithGroup on the receiver's
+// handler.
+func (l *Logger) WithGroup(name string) *Logger {
+ c := l.clone()
+ c.handler = l.handler.WithGroup(name)
+ return c
+
+}
+
+// New creates a new Logger with the given non-nil Handler and a nil context.
+func New(h Handler) *Logger {
+ if h == nil {
+ panic("nil Handler")
+ }
+ return &Logger{handler: h}
+}
+
+// With calls Logger.With on the default logger.
+func With(args ...any) *Logger {
+ return Default().With(args...)
+}
+
+// Enabled reports whether l emits log records at the given context and level.
+func (l *Logger) Enabled(ctx context.Context, level Level) bool {
+ if ctx == nil {
+ ctx = context.Background()
+ }
+ return l.Handler().Enabled(ctx, level)
+}
+
+// NewLogLogger returns a new log.Logger such that each call to its Output method
+// dispatches a Record to the specified handler. The logger acts as a bridge from
+// the older log API to newer structured logging handlers.
+func NewLogLogger(h Handler, level Level) *log.Logger {
+ return log.New(&handlerWriter{h, level, true}, "", 0)
+}
+
+// Log emits a log record with the current time and the given level and message.
+// The Record's Attrs consist of the Logger's attributes followed by
+// the Attrs specified by args.
+//
+// The attribute arguments are processed as follows:
+// - If an argument is an Attr, it is used as is.
+// - If an argument is a string and this is not the last argument,
+// the following argument is treated as the value and the two are combined
+// into an Attr.
+// - Otherwise, the argument is treated as a value with key "!BADKEY".
+func (l *Logger) Log(ctx context.Context, level Level, msg string, args ...any) {
+ l.log(ctx, level, msg, args...)
+}
+
+// LogAttrs is a more efficient version of [Logger.Log] that accepts only Attrs.
+func (l *Logger) LogAttrs(ctx context.Context, level Level, msg string, attrs ...Attr) {
+ l.logAttrs(ctx, level, msg, attrs...)
+}
+
+// Debug logs at LevelDebug.
+func (l *Logger) Debug(msg string, args ...any) {
+ l.log(nil, LevelDebug, msg, args...)
+}
+
+// DebugCtx logs at LevelDebug with the given context.
+func (l *Logger) DebugCtx(ctx context.Context, msg string, args ...any) {
+ l.log(ctx, LevelDebug, msg, args...)
+}
+
+// Info logs at LevelInfo.
+func (l *Logger) Info(msg string, args ...any) {
+ l.log(nil, LevelInfo, msg, args...)
+}
+
+// InfoCtx logs at LevelInfo with the given context.
+func (l *Logger) InfoCtx(ctx context.Context, msg string, args ...any) {
+ l.log(ctx, LevelInfo, msg, args...)
+}
+
+// Warn logs at LevelWarn.
+func (l *Logger) Warn(msg string, args ...any) {
+ l.log(nil, LevelWarn, msg, args...)
+}
+
+// WarnCtx logs at LevelWarn with the given context.
+func (l *Logger) WarnCtx(ctx context.Context, msg string, args ...any) {
+ l.log(ctx, LevelWarn, msg, args...)
+}
+
+// Error logs at LevelError.
+func (l *Logger) Error(msg string, args ...any) {
+ l.log(nil, LevelError, msg, args...)
+}
+
+// ErrorCtx logs at LevelError with the given context.
+func (l *Logger) ErrorCtx(ctx context.Context, msg string, args ...any) {
+ l.log(ctx, LevelError, msg, args...)
+}
+
+// log is the low-level logging method for methods that take ...any.
+// It must always be called directly by an exported logging method
+// or function, because it uses a fixed call depth to obtain the pc.
+func (l *Logger) log(ctx context.Context, level Level, msg string, args ...any) {
+ if !l.Enabled(ctx, level) {
+ return
+ }
+ var pc uintptr
+ if !internal.IgnorePC {
+ var pcs [1]uintptr
+ // skip [runtime.Callers, this function, this function's caller]
+ runtime.Callers(3, pcs[:])
+ pc = pcs[0]
+ }
+ r := NewRecord(time.Now(), level, msg, pc)
+ r.Add(args...)
+ if ctx == nil {
+ ctx = context.Background()
+ }
+ _ = l.Handler().Handle(ctx, r)
+}
+
+// logAttrs is like [Logger.log], but for methods that take ...Attr.
+func (l *Logger) logAttrs(ctx context.Context, level Level, msg string, attrs ...Attr) {
+ if !l.Enabled(ctx, level) {
+ return
+ }
+ var pc uintptr
+ if !internal.IgnorePC {
+ var pcs [1]uintptr
+ // skip [runtime.Callers, this function, this function's caller]
+ runtime.Callers(3, pcs[:])
+ pc = pcs[0]
+ }
+ r := NewRecord(time.Now(), level, msg, pc)
+ r.AddAttrs(attrs...)
+ if ctx == nil {
+ ctx = context.Background()
+ }
+ _ = l.Handler().Handle(ctx, r)
+}
+
+// Debug calls Logger.Debug on the default logger.
+func Debug(msg string, args ...any) {
+ Default().log(nil, LevelDebug, msg, args...)
+}
+
+// DebugCtx calls Logger.DebugCtx on the default logger.
+func DebugCtx(ctx context.Context, msg string, args ...any) {
+ Default().log(ctx, LevelDebug, msg, args...)
+}
+
+// Info calls Logger.Info on the default logger.
+func Info(msg string, args ...any) {
+ Default().log(nil, LevelInfo, msg, args...)
+}
+
+// InfoCtx calls Logger.InfoCtx on the default logger.
+func InfoCtx(ctx context.Context, msg string, args ...any) {
+ Default().log(ctx, LevelInfo, msg, args...)
+}
+
+// Warn calls Logger.Warn on the default logger.
+func Warn(msg string, args ...any) {
+ Default().log(nil, LevelWarn, msg, args...)
+}
+
+// WarnCtx calls Logger.WarnCtx on the default logger.
+func WarnCtx(ctx context.Context, msg string, args ...any) {
+ Default().log(ctx, LevelWarn, msg, args...)
+}
+
+// Error calls Logger.Error on the default logger.
+func Error(msg string, args ...any) {
+ Default().log(nil, LevelError, msg, args...)
+}
+
+// ErrorCtx calls Logger.ErrorCtx on the default logger.
+func ErrorCtx(ctx context.Context, msg string, args ...any) {
+ Default().log(ctx, LevelError, msg, args...)
+}
+
+// Log calls Logger.Log on the default logger.
+func Log(ctx context.Context, level Level, msg string, args ...any) {
+ Default().log(ctx, level, msg, args...)
+}
+
+// LogAttrs calls Logger.LogAttrs on the default logger.
+func LogAttrs(ctx context.Context, level Level, msg string, attrs ...Attr) {
+ Default().logAttrs(ctx, level, msg, attrs...)
+}
diff --git a/vendor/golang.org/x/exp/slog/noplog.bench b/vendor/golang.org/x/exp/slog/noplog.bench
new file mode 100644
index 0000000..ed9296f
--- /dev/null
+++ b/vendor/golang.org/x/exp/slog/noplog.bench
@@ -0,0 +1,36 @@
+goos: linux
+goarch: amd64
+pkg: golang.org/x/exp/slog
+cpu: Intel(R) Xeon(R) CPU @ 2.20GHz
+BenchmarkNopLog/attrs-8 1000000 1090 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/attrs-8 1000000 1097 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/attrs-8 1000000 1078 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/attrs-8 1000000 1095 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/attrs-8 1000000 1096 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/attrs-parallel-8 4007268 308.2 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/attrs-parallel-8 4016138 299.7 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/attrs-parallel-8 4020529 305.9 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/attrs-parallel-8 3977829 303.4 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/attrs-parallel-8 3225438 318.5 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/keys-values-8 1179256 994.2 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/keys-values-8 1000000 1002 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/keys-values-8 1216710 993.2 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/keys-values-8 1000000 1013 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/keys-values-8 1000000 1016 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/WithContext-8 989066 1163 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/WithContext-8 994116 1163 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/WithContext-8 1000000 1152 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/WithContext-8 991675 1165 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/WithContext-8 965268 1166 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/WithContext-parallel-8 3955503 303.3 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/WithContext-parallel-8 3861188 307.8 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/WithContext-parallel-8 3967752 303.9 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/WithContext-parallel-8 3955203 302.7 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/WithContext-parallel-8 3948278 301.1 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/Ctx-8 940622 1247 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/Ctx-8 936381 1257 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/Ctx-8 959730 1266 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/Ctx-8 943473 1290 ns/op 0 B/op 0 allocs/op
+BenchmarkNopLog/Ctx-8 919414 1259 ns/op 0 B/op 0 allocs/op
+PASS
+ok golang.org/x/exp/slog 40.566s
diff --git a/vendor/golang.org/x/exp/slog/record.go b/vendor/golang.org/x/exp/slog/record.go
new file mode 100644
index 0000000..38b3440
--- /dev/null
+++ b/vendor/golang.org/x/exp/slog/record.go
@@ -0,0 +1,207 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package slog
+
+import (
+ "runtime"
+ "time"
+
+ "golang.org/x/exp/slices"
+)
+
+const nAttrsInline = 5
+
+// A Record holds information about a log event.
+// Copies of a Record share state.
+// Do not modify a Record after handing out a copy to it.
+// Use [Record.Clone] to create a copy with no shared state.
+type Record struct {
+ // The time at which the output method (Log, Info, etc.) was called.
+ Time time.Time
+
+ // The log message.
+ Message string
+
+ // The level of the event.
+ Level Level
+
+ // The program counter at the time the record was constructed, as determined
+ // by runtime.Callers. If zero, no program counter is available.
+ //
+ // The only valid use for this value is as an argument to
+ // [runtime.CallersFrames]. In particular, it must not be passed to
+ // [runtime.FuncForPC].
+ PC uintptr
+
+ // Allocation optimization: an inline array sized to hold
+ // the majority of log calls (based on examination of open-source
+ // code). It holds the start of the list of Attrs.
+ front [nAttrsInline]Attr
+
+ // The number of Attrs in front.
+ nFront int
+
+ // The list of Attrs except for those in front.
+ // Invariants:
+ // - len(back) > 0 iff nFront == len(front)
+ // - Unused array elements are zero. Used to detect mistakes.
+ back []Attr
+}
+
+// NewRecord creates a Record from the given arguments.
+// Use [Record.AddAttrs] to add attributes to the Record.
+//
+// NewRecord is intended for logging APIs that want to support a [Handler] as
+// a backend.
+func NewRecord(t time.Time, level Level, msg string, pc uintptr) Record {
+ return Record{
+ Time: t,
+ Message: msg,
+ Level: level,
+ PC: pc,
+ }
+}
+
+// Clone returns a copy of the record with no shared state.
+// The original record and the clone can both be modified
+// without interfering with each other.
+func (r Record) Clone() Record {
+ r.back = slices.Clip(r.back) // prevent append from mutating shared array
+ return r
+}
+
+// NumAttrs returns the number of attributes in the Record.
+func (r Record) NumAttrs() int {
+ return r.nFront + len(r.back)
+}
+
+// Attrs calls f on each Attr in the Record.
+// Iteration stops if f returns false.
+func (r Record) Attrs(f func(Attr) bool) {
+ for i := 0; i < r.nFront; i++ {
+ if !f(r.front[i]) {
+ return
+ }
+ }
+ for _, a := range r.back {
+ if !f(a) {
+ return
+ }
+ }
+}
+
+// AddAttrs appends the given Attrs to the Record's list of Attrs.
+func (r *Record) AddAttrs(attrs ...Attr) {
+ n := copy(r.front[r.nFront:], attrs)
+ r.nFront += n
+ // Check if a copy was modified by slicing past the end
+ // and seeing if the Attr there is non-zero.
+ if cap(r.back) > len(r.back) {
+ end := r.back[:len(r.back)+1][len(r.back)]
+ if !end.isEmpty() {
+ panic("copies of a slog.Record were both modified")
+ }
+ }
+ r.back = append(r.back, attrs[n:]...)
+}
+
+// Add converts the args to Attrs as described in [Logger.Log],
+// then appends the Attrs to the Record's list of Attrs.
+func (r *Record) Add(args ...any) {
+ var a Attr
+ for len(args) > 0 {
+ a, args = argsToAttr(args)
+ if r.nFront < len(r.front) {
+ r.front[r.nFront] = a
+ r.nFront++
+ } else {
+ if r.back == nil {
+ r.back = make([]Attr, 0, countAttrs(args))
+ }
+ r.back = append(r.back, a)
+ }
+ }
+
+}
+
+// countAttrs returns the number of Attrs that would be created from args.
+func countAttrs(args []any) int {
+ n := 0
+ for i := 0; i < len(args); i++ {
+ n++
+ if _, ok := args[i].(string); ok {
+ i++
+ }
+ }
+ return n
+}
+
+const badKey = "!BADKEY"
+
+// argsToAttr turns a prefix of the nonempty args slice into an Attr
+// and returns the unconsumed portion of the slice.
+// If args[0] is an Attr, it returns it.
+// If args[0] is a string, it treats the first two elements as
+// a key-value pair.
+// Otherwise, it treats args[0] as a value with a missing key.
+func argsToAttr(args []any) (Attr, []any) {
+ switch x := args[0].(type) {
+ case string:
+ if len(args) == 1 {
+ return String(badKey, x), nil
+ }
+ return Any(x, args[1]), args[2:]
+
+ case Attr:
+ return x, args[1:]
+
+ default:
+ return Any(badKey, x), args[1:]
+ }
+}
+
+// Source describes the location of a line of source code.
+type Source struct {
+ // Function is the package path-qualified function name containing the
+ // source line. If non-empty, this string uniquely identifies a single
+ // function in the program. This may be the empty string if not known.
+ Function string `json:"function"`
+ // File and Line are the file name and line number (1-based) of the source
+ // line. These may be the empty string and zero, respectively, if not known.
+ File string `json:"file"`
+ Line int `json:"line"`
+}
+
+// attrs returns the non-zero fields of s as a slice of attrs.
+// It is similar to a LogValue method, but we don't want Source
+// to implement LogValuer because it would be resolved before
+// the ReplaceAttr function was called.
+func (s *Source) group() Value {
+ var as []Attr
+ if s.Function != "" {
+ as = append(as, String("function", s.Function))
+ }
+ if s.File != "" {
+ as = append(as, String("file", s.File))
+ }
+ if s.Line != 0 {
+ as = append(as, Int("line", s.Line))
+ }
+ return GroupValue(as...)
+}
+
+// source returns a Source for the log event.
+// If the Record was created without the necessary information,
+// or if the location is unavailable, it returns a non-nil *Source
+// with zero fields.
+func (r Record) source() *Source {
+ fs := runtime.CallersFrames([]uintptr{r.PC})
+ f, _ := fs.Next()
+ return &Source{
+ Function: f.Function,
+ File: f.File,
+ Line: f.Line,
+ }
+}
diff --git a/vendor/golang.org/x/exp/slog/text_handler.go b/vendor/golang.org/x/exp/slog/text_handler.go
new file mode 100644
index 0000000..75b66b7
--- /dev/null
+++ b/vendor/golang.org/x/exp/slog/text_handler.go
@@ -0,0 +1,161 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package slog
+
+import (
+ "context"
+ "encoding"
+ "fmt"
+ "io"
+ "reflect"
+ "strconv"
+ "unicode"
+ "unicode/utf8"
+)
+
+// TextHandler is a Handler that writes Records to an io.Writer as a
+// sequence of key=value pairs separated by spaces and followed by a newline.
+type TextHandler struct {
+ *commonHandler
+}
+
+// NewTextHandler creates a TextHandler that writes to w,
+// using the given options.
+// If opts is nil, the default options are used.
+func NewTextHandler(w io.Writer, opts *HandlerOptions) *TextHandler {
+ if opts == nil {
+ opts = &HandlerOptions{}
+ }
+ return &TextHandler{
+ &commonHandler{
+ json: false,
+ w: w,
+ opts: *opts,
+ },
+ }
+}
+
+// Enabled reports whether the handler handles records at the given level.
+// The handler ignores records whose level is lower.
+func (h *TextHandler) Enabled(_ context.Context, level Level) bool {
+ return h.commonHandler.enabled(level)
+}
+
+// WithAttrs returns a new TextHandler whose attributes consists
+// of h's attributes followed by attrs.
+func (h *TextHandler) WithAttrs(attrs []Attr) Handler {
+ return &TextHandler{commonHandler: h.commonHandler.withAttrs(attrs)}
+}
+
+func (h *TextHandler) WithGroup(name string) Handler {
+ return &TextHandler{commonHandler: h.commonHandler.withGroup(name)}
+}
+
+// Handle formats its argument Record as a single line of space-separated
+// key=value items.
+//
+// If the Record's time is zero, the time is omitted.
+// Otherwise, the key is "time"
+// and the value is output in RFC3339 format with millisecond precision.
+//
+// If the Record's level is zero, the level is omitted.
+// Otherwise, the key is "level"
+// and the value of [Level.String] is output.
+//
+// If the AddSource option is set and source information is available,
+// the key is "source" and the value is output as FILE:LINE.
+//
+// The message's key is "msg".
+//
+// To modify these or other attributes, or remove them from the output, use
+// [HandlerOptions.ReplaceAttr].
+//
+// If a value implements [encoding.TextMarshaler], the result of MarshalText is
+// written. Otherwise, the result of fmt.Sprint is written.
+//
+// Keys and values are quoted with [strconv.Quote] if they contain Unicode space
+// characters, non-printing characters, '"' or '='.
+//
+// Keys inside groups consist of components (keys or group names) separated by
+// dots. No further escaping is performed.
+// Thus there is no way to determine from the key "a.b.c" whether there
+// are two groups "a" and "b" and a key "c", or a single group "a.b" and a key "c",
+// or single group "a" and a key "b.c".
+// If it is necessary to reconstruct the group structure of a key
+// even in the presence of dots inside components, use
+// [HandlerOptions.ReplaceAttr] to encode that information in the key.
+//
+// Each call to Handle results in a single serialized call to
+// io.Writer.Write.
+func (h *TextHandler) Handle(_ context.Context, r Record) error {
+ return h.commonHandler.handle(r)
+}
+
+func appendTextValue(s *handleState, v Value) error {
+ switch v.Kind() {
+ case KindString:
+ s.appendString(v.str())
+ case KindTime:
+ s.appendTime(v.time())
+ case KindAny:
+ if tm, ok := v.any.(encoding.TextMarshaler); ok {
+ data, err := tm.MarshalText()
+ if err != nil {
+ return err
+ }
+ // TODO: avoid the conversion to string.
+ s.appendString(string(data))
+ return nil
+ }
+ if bs, ok := byteSlice(v.any); ok {
+ // As of Go 1.19, this only allocates for strings longer than 32 bytes.
+ s.buf.WriteString(strconv.Quote(string(bs)))
+ return nil
+ }
+ s.appendString(fmt.Sprintf("%+v", v.Any()))
+ default:
+ *s.buf = v.append(*s.buf)
+ }
+ return nil
+}
+
+// byteSlice returns its argument as a []byte if the argument's
+// underlying type is []byte, along with a second return value of true.
+// Otherwise it returns nil, false.
+func byteSlice(a any) ([]byte, bool) {
+ if bs, ok := a.([]byte); ok {
+ return bs, true
+ }
+ // Like Printf's %s, we allow both the slice type and the byte element type to be named.
+ t := reflect.TypeOf(a)
+ if t != nil && t.Kind() == reflect.Slice && t.Elem().Kind() == reflect.Uint8 {
+ return reflect.ValueOf(a).Bytes(), true
+ }
+ return nil, false
+}
+
+func needsQuoting(s string) bool {
+ if len(s) == 0 {
+ return true
+ }
+ for i := 0; i < len(s); {
+ b := s[i]
+ if b < utf8.RuneSelf {
+ // Quote anything except a backslash that would need quoting in a
+ // JSON string, as well as space and '='
+ if b != '\\' && (b == ' ' || b == '=' || !safeSet[b]) {
+ return true
+ }
+ i++
+ continue
+ }
+ r, size := utf8.DecodeRuneInString(s[i:])
+ if r == utf8.RuneError || unicode.IsSpace(r) || !unicode.IsPrint(r) {
+ return true
+ }
+ i += size
+ }
+ return false
+}
diff --git a/vendor/golang.org/x/exp/slog/value.go b/vendor/golang.org/x/exp/slog/value.go
new file mode 100644
index 0000000..df9b047
--- /dev/null
+++ b/vendor/golang.org/x/exp/slog/value.go
@@ -0,0 +1,456 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package slog
+
+import (
+ "fmt"
+ "math"
+ "runtime"
+ "strconv"
+ "strings"
+ "time"
+ "unsafe"
+
+ "golang.org/x/exp/slices"
+)
+
+// A Value can represent any Go value, but unlike type any,
+// it can represent most small values without an allocation.
+// The zero Value corresponds to nil.
+type Value struct {
+ _ [0]func() // disallow ==
+ // num holds the value for Kinds Int64, Uint64, Float64, Bool and Duration,
+ // the string length for KindString, and nanoseconds since the epoch for KindTime.
+ num uint64
+ // If any is of type Kind, then the value is in num as described above.
+ // If any is of type *time.Location, then the Kind is Time and time.Time value
+ // can be constructed from the Unix nanos in num and the location (monotonic time
+ // is not preserved).
+ // If any is of type stringptr, then the Kind is String and the string value
+ // consists of the length in num and the pointer in any.
+ // Otherwise, the Kind is Any and any is the value.
+ // (This implies that Attrs cannot store values of type Kind, *time.Location
+ // or stringptr.)
+ any any
+}
+
+// Kind is the kind of a Value.
+type Kind int
+
+// The following list is sorted alphabetically, but it's also important that
+// KindAny is 0 so that a zero Value represents nil.
+
+const (
+ KindAny Kind = iota
+ KindBool
+ KindDuration
+ KindFloat64
+ KindInt64
+ KindString
+ KindTime
+ KindUint64
+ KindGroup
+ KindLogValuer
+)
+
+var kindStrings = []string{
+ "Any",
+ "Bool",
+ "Duration",
+ "Float64",
+ "Int64",
+ "String",
+ "Time",
+ "Uint64",
+ "Group",
+ "LogValuer",
+}
+
+func (k Kind) String() string {
+ if k >= 0 && int(k) < len(kindStrings) {
+ return kindStrings[k]
+ }
+ return ""
+}
+
+// Unexported version of Kind, just so we can store Kinds in Values.
+// (No user-provided value has this type.)
+type kind Kind
+
+// Kind returns v's Kind.
+func (v Value) Kind() Kind {
+ switch x := v.any.(type) {
+ case Kind:
+ return x
+ case stringptr:
+ return KindString
+ case timeLocation:
+ return KindTime
+ case groupptr:
+ return KindGroup
+ case LogValuer:
+ return KindLogValuer
+ case kind: // a kind is just a wrapper for a Kind
+ return KindAny
+ default:
+ return KindAny
+ }
+}
+
+//////////////// Constructors
+
+// IntValue returns a Value for an int.
+func IntValue(v int) Value {
+ return Int64Value(int64(v))
+}
+
+// Int64Value returns a Value for an int64.
+func Int64Value(v int64) Value {
+ return Value{num: uint64(v), any: KindInt64}
+}
+
+// Uint64Value returns a Value for a uint64.
+func Uint64Value(v uint64) Value {
+ return Value{num: v, any: KindUint64}
+}
+
+// Float64Value returns a Value for a floating-point number.
+func Float64Value(v float64) Value {
+ return Value{num: math.Float64bits(v), any: KindFloat64}
+}
+
+// BoolValue returns a Value for a bool.
+func BoolValue(v bool) Value {
+ u := uint64(0)
+ if v {
+ u = 1
+ }
+ return Value{num: u, any: KindBool}
+}
+
+// Unexported version of *time.Location, just so we can store *time.Locations in
+// Values. (No user-provided value has this type.)
+type timeLocation *time.Location
+
+// TimeValue returns a Value for a time.Time.
+// It discards the monotonic portion.
+func TimeValue(v time.Time) Value {
+ if v.IsZero() {
+ // UnixNano on the zero time is undefined, so represent the zero time
+ // with a nil *time.Location instead. time.Time.Location method never
+ // returns nil, so a Value with any == timeLocation(nil) cannot be
+ // mistaken for any other Value, time.Time or otherwise.
+ return Value{any: timeLocation(nil)}
+ }
+ return Value{num: uint64(v.UnixNano()), any: timeLocation(v.Location())}
+}
+
+// DurationValue returns a Value for a time.Duration.
+func DurationValue(v time.Duration) Value {
+ return Value{num: uint64(v.Nanoseconds()), any: KindDuration}
+}
+
+// AnyValue returns a Value for the supplied value.
+//
+// If the supplied value is of type Value, it is returned
+// unmodified.
+//
+// Given a value of one of Go's predeclared string, bool, or
+// (non-complex) numeric types, AnyValue returns a Value of kind
+// String, Bool, Uint64, Int64, or Float64. The width of the
+// original numeric type is not preserved.
+//
+// Given a time.Time or time.Duration value, AnyValue returns a Value of kind
+// KindTime or KindDuration. The monotonic time is not preserved.
+//
+// For nil, or values of all other types, including named types whose
+// underlying type is numeric, AnyValue returns a value of kind KindAny.
+func AnyValue(v any) Value {
+ switch v := v.(type) {
+ case string:
+ return StringValue(v)
+ case int:
+ return Int64Value(int64(v))
+ case uint:
+ return Uint64Value(uint64(v))
+ case int64:
+ return Int64Value(v)
+ case uint64:
+ return Uint64Value(v)
+ case bool:
+ return BoolValue(v)
+ case time.Duration:
+ return DurationValue(v)
+ case time.Time:
+ return TimeValue(v)
+ case uint8:
+ return Uint64Value(uint64(v))
+ case uint16:
+ return Uint64Value(uint64(v))
+ case uint32:
+ return Uint64Value(uint64(v))
+ case uintptr:
+ return Uint64Value(uint64(v))
+ case int8:
+ return Int64Value(int64(v))
+ case int16:
+ return Int64Value(int64(v))
+ case int32:
+ return Int64Value(int64(v))
+ case float64:
+ return Float64Value(v)
+ case float32:
+ return Float64Value(float64(v))
+ case []Attr:
+ return GroupValue(v...)
+ case Kind:
+ return Value{any: kind(v)}
+ case Value:
+ return v
+ default:
+ return Value{any: v}
+ }
+}
+
+//////////////// Accessors
+
+// Any returns v's value as an any.
+func (v Value) Any() any {
+ switch v.Kind() {
+ case KindAny:
+ if k, ok := v.any.(kind); ok {
+ return Kind(k)
+ }
+ return v.any
+ case KindLogValuer:
+ return v.any
+ case KindGroup:
+ return v.group()
+ case KindInt64:
+ return int64(v.num)
+ case KindUint64:
+ return v.num
+ case KindFloat64:
+ return v.float()
+ case KindString:
+ return v.str()
+ case KindBool:
+ return v.bool()
+ case KindDuration:
+ return v.duration()
+ case KindTime:
+ return v.time()
+ default:
+ panic(fmt.Sprintf("bad kind: %s", v.Kind()))
+ }
+}
+
+// Int64 returns v's value as an int64. It panics
+// if v is not a signed integer.
+func (v Value) Int64() int64 {
+ if g, w := v.Kind(), KindInt64; g != w {
+ panic(fmt.Sprintf("Value kind is %s, not %s", g, w))
+ }
+ return int64(v.num)
+}
+
+// Uint64 returns v's value as a uint64. It panics
+// if v is not an unsigned integer.
+func (v Value) Uint64() uint64 {
+ if g, w := v.Kind(), KindUint64; g != w {
+ panic(fmt.Sprintf("Value kind is %s, not %s", g, w))
+ }
+ return v.num
+}
+
+// Bool returns v's value as a bool. It panics
+// if v is not a bool.
+func (v Value) Bool() bool {
+ if g, w := v.Kind(), KindBool; g != w {
+ panic(fmt.Sprintf("Value kind is %s, not %s", g, w))
+ }
+ return v.bool()
+}
+
+func (a Value) bool() bool {
+ return a.num == 1
+}
+
+// Duration returns v's value as a time.Duration. It panics
+// if v is not a time.Duration.
+func (a Value) Duration() time.Duration {
+ if g, w := a.Kind(), KindDuration; g != w {
+ panic(fmt.Sprintf("Value kind is %s, not %s", g, w))
+ }
+
+ return a.duration()
+}
+
+func (a Value) duration() time.Duration {
+ return time.Duration(int64(a.num))
+}
+
+// Float64 returns v's value as a float64. It panics
+// if v is not a float64.
+func (v Value) Float64() float64 {
+ if g, w := v.Kind(), KindFloat64; g != w {
+ panic(fmt.Sprintf("Value kind is %s, not %s", g, w))
+ }
+
+ return v.float()
+}
+
+func (a Value) float() float64 {
+ return math.Float64frombits(a.num)
+}
+
+// Time returns v's value as a time.Time. It panics
+// if v is not a time.Time.
+func (v Value) Time() time.Time {
+ if g, w := v.Kind(), KindTime; g != w {
+ panic(fmt.Sprintf("Value kind is %s, not %s", g, w))
+ }
+ return v.time()
+}
+
+func (v Value) time() time.Time {
+ loc := v.any.(timeLocation)
+ if loc == nil {
+ return time.Time{}
+ }
+ return time.Unix(0, int64(v.num)).In(loc)
+}
+
+// LogValuer returns v's value as a LogValuer. It panics
+// if v is not a LogValuer.
+func (v Value) LogValuer() LogValuer {
+ return v.any.(LogValuer)
+}
+
+// Group returns v's value as a []Attr.
+// It panics if v's Kind is not KindGroup.
+func (v Value) Group() []Attr {
+ if sp, ok := v.any.(groupptr); ok {
+ return unsafe.Slice((*Attr)(sp), v.num)
+ }
+ panic("Group: bad kind")
+}
+
+func (v Value) group() []Attr {
+ return unsafe.Slice((*Attr)(v.any.(groupptr)), v.num)
+}
+
+//////////////// Other
+
+// Equal reports whether v and w represent the same Go value.
+func (v Value) Equal(w Value) bool {
+ k1 := v.Kind()
+ k2 := w.Kind()
+ if k1 != k2 {
+ return false
+ }
+ switch k1 {
+ case KindInt64, KindUint64, KindBool, KindDuration:
+ return v.num == w.num
+ case KindString:
+ return v.str() == w.str()
+ case KindFloat64:
+ return v.float() == w.float()
+ case KindTime:
+ return v.time().Equal(w.time())
+ case KindAny, KindLogValuer:
+ return v.any == w.any // may panic if non-comparable
+ case KindGroup:
+ return slices.EqualFunc(v.group(), w.group(), Attr.Equal)
+ default:
+ panic(fmt.Sprintf("bad kind: %s", k1))
+ }
+}
+
+// append appends a text representation of v to dst.
+// v is formatted as with fmt.Sprint.
+func (v Value) append(dst []byte) []byte {
+ switch v.Kind() {
+ case KindString:
+ return append(dst, v.str()...)
+ case KindInt64:
+ return strconv.AppendInt(dst, int64(v.num), 10)
+ case KindUint64:
+ return strconv.AppendUint(dst, v.num, 10)
+ case KindFloat64:
+ return strconv.AppendFloat(dst, v.float(), 'g', -1, 64)
+ case KindBool:
+ return strconv.AppendBool(dst, v.bool())
+ case KindDuration:
+ return append(dst, v.duration().String()...)
+ case KindTime:
+ return append(dst, v.time().String()...)
+ case KindGroup:
+ return fmt.Append(dst, v.group())
+ case KindAny, KindLogValuer:
+ return fmt.Append(dst, v.any)
+ default:
+ panic(fmt.Sprintf("bad kind: %s", v.Kind()))
+ }
+}
+
+// A LogValuer is any Go value that can convert itself into a Value for logging.
+//
+// This mechanism may be used to defer expensive operations until they are
+// needed, or to expand a single value into a sequence of components.
+type LogValuer interface {
+ LogValue() Value
+}
+
+const maxLogValues = 100
+
+// Resolve repeatedly calls LogValue on v while it implements LogValuer,
+// and returns the result.
+// If v resolves to a group, the group's attributes' values are not recursively
+// resolved.
+// If the number of LogValue calls exceeds a threshold, a Value containing an
+// error is returned.
+// Resolve's return value is guaranteed not to be of Kind KindLogValuer.
+func (v Value) Resolve() (rv Value) {
+ orig := v
+ defer func() {
+ if r := recover(); r != nil {
+ rv = AnyValue(fmt.Errorf("LogValue panicked\n%s", stack(3, 5)))
+ }
+ }()
+
+ for i := 0; i < maxLogValues; i++ {
+ if v.Kind() != KindLogValuer {
+ return v
+ }
+ v = v.LogValuer().LogValue()
+ }
+ err := fmt.Errorf("LogValue called too many times on Value of type %T", orig.Any())
+ return AnyValue(err)
+}
+
+func stack(skip, nFrames int) string {
+ pcs := make([]uintptr, nFrames+1)
+ n := runtime.Callers(skip+1, pcs)
+ if n == 0 {
+ return "(no stack)"
+ }
+ frames := runtime.CallersFrames(pcs[:n])
+ var b strings.Builder
+ i := 0
+ for {
+ frame, more := frames.Next()
+ fmt.Fprintf(&b, "called from %s (%s:%d)\n", frame.Function, frame.File, frame.Line)
+ if !more {
+ break
+ }
+ i++
+ if i >= nFrames {
+ fmt.Fprintf(&b, "(rest of stack elided)\n")
+ break
+ }
+ }
+ return b.String()
+}
diff --git a/vendor/golang.org/x/exp/slog/value_119.go b/vendor/golang.org/x/exp/slog/value_119.go
new file mode 100644
index 0000000..29b0d73
--- /dev/null
+++ b/vendor/golang.org/x/exp/slog/value_119.go
@@ -0,0 +1,53 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build go1.19 && !go1.20
+
+package slog
+
+import (
+ "reflect"
+ "unsafe"
+)
+
+type (
+ stringptr unsafe.Pointer // used in Value.any when the Value is a string
+ groupptr unsafe.Pointer // used in Value.any when the Value is a []Attr
+)
+
+// StringValue returns a new Value for a string.
+func StringValue(value string) Value {
+ hdr := (*reflect.StringHeader)(unsafe.Pointer(&value))
+ return Value{num: uint64(hdr.Len), any: stringptr(hdr.Data)}
+}
+
+func (v Value) str() string {
+ var s string
+ hdr := (*reflect.StringHeader)(unsafe.Pointer(&s))
+ hdr.Data = uintptr(v.any.(stringptr))
+ hdr.Len = int(v.num)
+ return s
+}
+
+// String returns Value's value as a string, formatted like fmt.Sprint. Unlike
+// the methods Int64, Float64, and so on, which panic if v is of the
+// wrong kind, String never panics.
+func (v Value) String() string {
+ if sp, ok := v.any.(stringptr); ok {
+ // Inlining this code makes a huge difference.
+ var s string
+ hdr := (*reflect.StringHeader)(unsafe.Pointer(&s))
+ hdr.Data = uintptr(sp)
+ hdr.Len = int(v.num)
+ return s
+ }
+ return string(v.append(nil))
+}
+
+// GroupValue returns a new Value for a list of Attrs.
+// The caller must not subsequently mutate the argument slice.
+func GroupValue(as ...Attr) Value {
+ hdr := (*reflect.SliceHeader)(unsafe.Pointer(&as))
+ return Value{num: uint64(hdr.Len), any: groupptr(hdr.Data)}
+}
diff --git a/vendor/golang.org/x/exp/slog/value_120.go b/vendor/golang.org/x/exp/slog/value_120.go
new file mode 100644
index 0000000..f7d4c09
--- /dev/null
+++ b/vendor/golang.org/x/exp/slog/value_120.go
@@ -0,0 +1,39 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build go1.20
+
+package slog
+
+import "unsafe"
+
+type (
+ stringptr *byte // used in Value.any when the Value is a string
+ groupptr *Attr // used in Value.any when the Value is a []Attr
+)
+
+// StringValue returns a new Value for a string.
+func StringValue(value string) Value {
+ return Value{num: uint64(len(value)), any: stringptr(unsafe.StringData(value))}
+}
+
+// GroupValue returns a new Value for a list of Attrs.
+// The caller must not subsequently mutate the argument slice.
+func GroupValue(as ...Attr) Value {
+ return Value{num: uint64(len(as)), any: groupptr(unsafe.SliceData(as))}
+}
+
+// String returns Value's value as a string, formatted like fmt.Sprint. Unlike
+// the methods Int64, Float64, and so on, which panic if v is of the
+// wrong kind, String never panics.
+func (v Value) String() string {
+ if sp, ok := v.any.(stringptr); ok {
+ return unsafe.String(sp, v.num)
+ }
+ return string(v.append(nil))
+}
+
+func (v Value) str() string {
+ return unsafe.String(v.any.(stringptr), v.num)
+}
diff --git a/vendor/golang.org/x/tools/go/ast/astutil/enclosing.go b/vendor/golang.org/x/tools/go/ast/astutil/enclosing.go
new file mode 100644
index 0000000..9fa5aa1
--- /dev/null
+++ b/vendor/golang.org/x/tools/go/ast/astutil/enclosing.go
@@ -0,0 +1,636 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package astutil
+
+// This file defines utilities for working with source positions.
+
+import (
+ "fmt"
+ "go/ast"
+ "go/token"
+ "sort"
+
+ "golang.org/x/tools/internal/typeparams"
+)
+
+// PathEnclosingInterval returns the node that encloses the source
+// interval [start, end), and all its ancestors up to the AST root.
+//
+// The definition of "enclosing" used by this function considers
+// additional whitespace abutting a node to be enclosed by it.
+// In this example:
+//
+// z := x + y // add them
+// <-A->
+// <----B----->
+//
+// the ast.BinaryExpr(+) node is considered to enclose interval B
+// even though its [Pos()..End()) is actually only interval A.
+// This behaviour makes user interfaces more tolerant of imperfect
+// input.
+//
+// This function treats tokens as nodes, though they are not included
+// in the result. e.g. PathEnclosingInterval("+") returns the
+// enclosing ast.BinaryExpr("x + y").
+//
+// If start==end, the 1-char interval following start is used instead.
+//
+// The 'exact' result is true if the interval contains only path[0]
+// and perhaps some adjacent whitespace. It is false if the interval
+// overlaps multiple children of path[0], or if it contains only
+// interior whitespace of path[0].
+// In this example:
+//
+// z := x + y // add them
+// <--C--> <---E-->
+// ^
+// D
+//
+// intervals C, D and E are inexact. C is contained by the
+// z-assignment statement, because it spans three of its children (:=,
+// x, +). So too is the 1-char interval D, because it contains only
+// interior whitespace of the assignment. E is considered interior
+// whitespace of the BlockStmt containing the assignment.
+//
+// The resulting path is never empty; it always contains at least the
+// 'root' *ast.File. Ideally PathEnclosingInterval would reject
+// intervals that lie wholly or partially outside the range of the
+// file, but unfortunately ast.File records only the token.Pos of
+// the 'package' keyword, but not of the start of the file itself.
+func PathEnclosingInterval(root *ast.File, start, end token.Pos) (path []ast.Node, exact bool) {
+ // fmt.Printf("EnclosingInterval %d %d\n", start, end) // debugging
+
+ // Precondition: node.[Pos..End) and adjoining whitespace contain [start, end).
+ var visit func(node ast.Node) bool
+ visit = func(node ast.Node) bool {
+ path = append(path, node)
+
+ nodePos := node.Pos()
+ nodeEnd := node.End()
+
+ // fmt.Printf("visit(%T, %d, %d)\n", node, nodePos, nodeEnd) // debugging
+
+ // Intersect [start, end) with interval of node.
+ if start < nodePos {
+ start = nodePos
+ }
+ if end > nodeEnd {
+ end = nodeEnd
+ }
+
+ // Find sole child that contains [start, end).
+ children := childrenOf(node)
+ l := len(children)
+ for i, child := range children {
+ // [childPos, childEnd) is unaugmented interval of child.
+ childPos := child.Pos()
+ childEnd := child.End()
+
+ // [augPos, augEnd) is whitespace-augmented interval of child.
+ augPos := childPos
+ augEnd := childEnd
+ if i > 0 {
+ augPos = children[i-1].End() // start of preceding whitespace
+ }
+ if i < l-1 {
+ nextChildPos := children[i+1].Pos()
+ // Does [start, end) lie between child and next child?
+ if start >= augEnd && end <= nextChildPos {
+ return false // inexact match
+ }
+ augEnd = nextChildPos // end of following whitespace
+ }
+
+ // fmt.Printf("\tchild %d: [%d..%d)\tcontains interval [%d..%d)?\n",
+ // i, augPos, augEnd, start, end) // debugging
+
+ // Does augmented child strictly contain [start, end)?
+ if augPos <= start && end <= augEnd {
+ _, isToken := child.(tokenNode)
+ return isToken || visit(child)
+ }
+
+ // Does [start, end) overlap multiple children?
+ // i.e. left-augmented child contains start
+ // but LR-augmented child does not contain end.
+ if start < childEnd && end > augEnd {
+ break
+ }
+ }
+
+ // No single child contained [start, end),
+ // so node is the result. Is it exact?
+
+ // (It's tempting to put this condition before the
+ // child loop, but it gives the wrong result in the
+ // case where a node (e.g. ExprStmt) and its sole
+ // child have equal intervals.)
+ if start == nodePos && end == nodeEnd {
+ return true // exact match
+ }
+
+ return false // inexact: overlaps multiple children
+ }
+
+ // Ensure [start,end) is nondecreasing.
+ if start > end {
+ start, end = end, start
+ }
+
+ if start < root.End() && end > root.Pos() {
+ if start == end {
+ end = start + 1 // empty interval => interval of size 1
+ }
+ exact = visit(root)
+
+ // Reverse the path:
+ for i, l := 0, len(path); i < l/2; i++ {
+ path[i], path[l-1-i] = path[l-1-i], path[i]
+ }
+ } else {
+ // Selection lies within whitespace preceding the
+ // first (or following the last) declaration in the file.
+ // The result nonetheless always includes the ast.File.
+ path = append(path, root)
+ }
+
+ return
+}
+
+// tokenNode is a dummy implementation of ast.Node for a single token.
+// They are used transiently by PathEnclosingInterval but never escape
+// this package.
+type tokenNode struct {
+ pos token.Pos
+ end token.Pos
+}
+
+func (n tokenNode) Pos() token.Pos {
+ return n.pos
+}
+
+func (n tokenNode) End() token.Pos {
+ return n.end
+}
+
+func tok(pos token.Pos, len int) ast.Node {
+ return tokenNode{pos, pos + token.Pos(len)}
+}
+
+// childrenOf returns the direct non-nil children of ast.Node n.
+// It may include fake ast.Node implementations for bare tokens.
+// it is not safe to call (e.g.) ast.Walk on such nodes.
+func childrenOf(n ast.Node) []ast.Node {
+ var children []ast.Node
+
+ // First add nodes for all true subtrees.
+ ast.Inspect(n, func(node ast.Node) bool {
+ if node == n { // push n
+ return true // recur
+ }
+ if node != nil { // push child
+ children = append(children, node)
+ }
+ return false // no recursion
+ })
+
+ // Then add fake Nodes for bare tokens.
+ switch n := n.(type) {
+ case *ast.ArrayType:
+ children = append(children,
+ tok(n.Lbrack, len("[")),
+ tok(n.Elt.End(), len("]")))
+
+ case *ast.AssignStmt:
+ children = append(children,
+ tok(n.TokPos, len(n.Tok.String())))
+
+ case *ast.BasicLit:
+ children = append(children,
+ tok(n.ValuePos, len(n.Value)))
+
+ case *ast.BinaryExpr:
+ children = append(children, tok(n.OpPos, len(n.Op.String())))
+
+ case *ast.BlockStmt:
+ children = append(children,
+ tok(n.Lbrace, len("{")),
+ tok(n.Rbrace, len("}")))
+
+ case *ast.BranchStmt:
+ children = append(children,
+ tok(n.TokPos, len(n.Tok.String())))
+
+ case *ast.CallExpr:
+ children = append(children,
+ tok(n.Lparen, len("(")),
+ tok(n.Rparen, len(")")))
+ if n.Ellipsis != 0 {
+ children = append(children, tok(n.Ellipsis, len("...")))
+ }
+
+ case *ast.CaseClause:
+ if n.List == nil {
+ children = append(children,
+ tok(n.Case, len("default")))
+ } else {
+ children = append(children,
+ tok(n.Case, len("case")))
+ }
+ children = append(children, tok(n.Colon, len(":")))
+
+ case *ast.ChanType:
+ switch n.Dir {
+ case ast.RECV:
+ children = append(children, tok(n.Begin, len("<-chan")))
+ case ast.SEND:
+ children = append(children, tok(n.Begin, len("chan<-")))
+ case ast.RECV | ast.SEND:
+ children = append(children, tok(n.Begin, len("chan")))
+ }
+
+ case *ast.CommClause:
+ if n.Comm == nil {
+ children = append(children,
+ tok(n.Case, len("default")))
+ } else {
+ children = append(children,
+ tok(n.Case, len("case")))
+ }
+ children = append(children, tok(n.Colon, len(":")))
+
+ case *ast.Comment:
+ // nop
+
+ case *ast.CommentGroup:
+ // nop
+
+ case *ast.CompositeLit:
+ children = append(children,
+ tok(n.Lbrace, len("{")),
+ tok(n.Rbrace, len("{")))
+
+ case *ast.DeclStmt:
+ // nop
+
+ case *ast.DeferStmt:
+ children = append(children,
+ tok(n.Defer, len("defer")))
+
+ case *ast.Ellipsis:
+ children = append(children,
+ tok(n.Ellipsis, len("...")))
+
+ case *ast.EmptyStmt:
+ // nop
+
+ case *ast.ExprStmt:
+ // nop
+
+ case *ast.Field:
+ // TODO(adonovan): Field.{Doc,Comment,Tag}?
+
+ case *ast.FieldList:
+ children = append(children,
+ tok(n.Opening, len("(")), // or len("[")
+ tok(n.Closing, len(")"))) // or len("]")
+
+ case *ast.File:
+ // TODO test: Doc
+ children = append(children,
+ tok(n.Package, len("package")))
+
+ case *ast.ForStmt:
+ children = append(children,
+ tok(n.For, len("for")))
+
+ case *ast.FuncDecl:
+ // TODO(adonovan): FuncDecl.Comment?
+
+ // Uniquely, FuncDecl breaks the invariant that
+ // preorder traversal yields tokens in lexical order:
+ // in fact, FuncDecl.Recv precedes FuncDecl.Type.Func.
+ //
+ // As a workaround, we inline the case for FuncType
+ // here and order things correctly.
+ //
+ children = nil // discard ast.Walk(FuncDecl) info subtrees
+ children = append(children, tok(n.Type.Func, len("func")))
+ if n.Recv != nil {
+ children = append(children, n.Recv)
+ }
+ children = append(children, n.Name)
+ if tparams := typeparams.ForFuncType(n.Type); tparams != nil {
+ children = append(children, tparams)
+ }
+ if n.Type.Params != nil {
+ children = append(children, n.Type.Params)
+ }
+ if n.Type.Results != nil {
+ children = append(children, n.Type.Results)
+ }
+ if n.Body != nil {
+ children = append(children, n.Body)
+ }
+
+ case *ast.FuncLit:
+ // nop
+
+ case *ast.FuncType:
+ if n.Func != 0 {
+ children = append(children,
+ tok(n.Func, len("func")))
+ }
+
+ case *ast.GenDecl:
+ children = append(children,
+ tok(n.TokPos, len(n.Tok.String())))
+ if n.Lparen != 0 {
+ children = append(children,
+ tok(n.Lparen, len("(")),
+ tok(n.Rparen, len(")")))
+ }
+
+ case *ast.GoStmt:
+ children = append(children,
+ tok(n.Go, len("go")))
+
+ case *ast.Ident:
+ children = append(children,
+ tok(n.NamePos, len(n.Name)))
+
+ case *ast.IfStmt:
+ children = append(children,
+ tok(n.If, len("if")))
+
+ case *ast.ImportSpec:
+ // TODO(adonovan): ImportSpec.{Doc,EndPos}?
+
+ case *ast.IncDecStmt:
+ children = append(children,
+ tok(n.TokPos, len(n.Tok.String())))
+
+ case *ast.IndexExpr:
+ children = append(children,
+ tok(n.Lbrack, len("[")),
+ tok(n.Rbrack, len("]")))
+
+ case *typeparams.IndexListExpr:
+ children = append(children,
+ tok(n.Lbrack, len("[")),
+ tok(n.Rbrack, len("]")))
+
+ case *ast.InterfaceType:
+ children = append(children,
+ tok(n.Interface, len("interface")))
+
+ case *ast.KeyValueExpr:
+ children = append(children,
+ tok(n.Colon, len(":")))
+
+ case *ast.LabeledStmt:
+ children = append(children,
+ tok(n.Colon, len(":")))
+
+ case *ast.MapType:
+ children = append(children,
+ tok(n.Map, len("map")))
+
+ case *ast.ParenExpr:
+ children = append(children,
+ tok(n.Lparen, len("(")),
+ tok(n.Rparen, len(")")))
+
+ case *ast.RangeStmt:
+ children = append(children,
+ tok(n.For, len("for")),
+ tok(n.TokPos, len(n.Tok.String())))
+
+ case *ast.ReturnStmt:
+ children = append(children,
+ tok(n.Return, len("return")))
+
+ case *ast.SelectStmt:
+ children = append(children,
+ tok(n.Select, len("select")))
+
+ case *ast.SelectorExpr:
+ // nop
+
+ case *ast.SendStmt:
+ children = append(children,
+ tok(n.Arrow, len("<-")))
+
+ case *ast.SliceExpr:
+ children = append(children,
+ tok(n.Lbrack, len("[")),
+ tok(n.Rbrack, len("]")))
+
+ case *ast.StarExpr:
+ children = append(children, tok(n.Star, len("*")))
+
+ case *ast.StructType:
+ children = append(children, tok(n.Struct, len("struct")))
+
+ case *ast.SwitchStmt:
+ children = append(children, tok(n.Switch, len("switch")))
+
+ case *ast.TypeAssertExpr:
+ children = append(children,
+ tok(n.Lparen-1, len(".")),
+ tok(n.Lparen, len("(")),
+ tok(n.Rparen, len(")")))
+
+ case *ast.TypeSpec:
+ // TODO(adonovan): TypeSpec.{Doc,Comment}?
+
+ case *ast.TypeSwitchStmt:
+ children = append(children, tok(n.Switch, len("switch")))
+
+ case *ast.UnaryExpr:
+ children = append(children, tok(n.OpPos, len(n.Op.String())))
+
+ case *ast.ValueSpec:
+ // TODO(adonovan): ValueSpec.{Doc,Comment}?
+
+ case *ast.BadDecl, *ast.BadExpr, *ast.BadStmt:
+ // nop
+ }
+
+ // TODO(adonovan): opt: merge the logic of ast.Inspect() into
+ // the switch above so we can make interleaved callbacks for
+ // both Nodes and Tokens in the right order and avoid the need
+ // to sort.
+ sort.Sort(byPos(children))
+
+ return children
+}
+
+type byPos []ast.Node
+
+func (sl byPos) Len() int {
+ return len(sl)
+}
+func (sl byPos) Less(i, j int) bool {
+ return sl[i].Pos() < sl[j].Pos()
+}
+func (sl byPos) Swap(i, j int) {
+ sl[i], sl[j] = sl[j], sl[i]
+}
+
+// NodeDescription returns a description of the concrete type of n suitable
+// for a user interface.
+//
+// TODO(adonovan): in some cases (e.g. Field, FieldList, Ident,
+// StarExpr) we could be much more specific given the path to the AST
+// root. Perhaps we should do that.
+func NodeDescription(n ast.Node) string {
+ switch n := n.(type) {
+ case *ast.ArrayType:
+ return "array type"
+ case *ast.AssignStmt:
+ return "assignment"
+ case *ast.BadDecl:
+ return "bad declaration"
+ case *ast.BadExpr:
+ return "bad expression"
+ case *ast.BadStmt:
+ return "bad statement"
+ case *ast.BasicLit:
+ return "basic literal"
+ case *ast.BinaryExpr:
+ return fmt.Sprintf("binary %s operation", n.Op)
+ case *ast.BlockStmt:
+ return "block"
+ case *ast.BranchStmt:
+ switch n.Tok {
+ case token.BREAK:
+ return "break statement"
+ case token.CONTINUE:
+ return "continue statement"
+ case token.GOTO:
+ return "goto statement"
+ case token.FALLTHROUGH:
+ return "fall-through statement"
+ }
+ case *ast.CallExpr:
+ if len(n.Args) == 1 && !n.Ellipsis.IsValid() {
+ return "function call (or conversion)"
+ }
+ return "function call"
+ case *ast.CaseClause:
+ return "case clause"
+ case *ast.ChanType:
+ return "channel type"
+ case *ast.CommClause:
+ return "communication clause"
+ case *ast.Comment:
+ return "comment"
+ case *ast.CommentGroup:
+ return "comment group"
+ case *ast.CompositeLit:
+ return "composite literal"
+ case *ast.DeclStmt:
+ return NodeDescription(n.Decl) + " statement"
+ case *ast.DeferStmt:
+ return "defer statement"
+ case *ast.Ellipsis:
+ return "ellipsis"
+ case *ast.EmptyStmt:
+ return "empty statement"
+ case *ast.ExprStmt:
+ return "expression statement"
+ case *ast.Field:
+ // Can be any of these:
+ // struct {x, y int} -- struct field(s)
+ // struct {T} -- anon struct field
+ // interface {I} -- interface embedding
+ // interface {f()} -- interface method
+ // func (A) func(B) C -- receiver, param(s), result(s)
+ return "field/method/parameter"
+ case *ast.FieldList:
+ return "field/method/parameter list"
+ case *ast.File:
+ return "source file"
+ case *ast.ForStmt:
+ return "for loop"
+ case *ast.FuncDecl:
+ return "function declaration"
+ case *ast.FuncLit:
+ return "function literal"
+ case *ast.FuncType:
+ return "function type"
+ case *ast.GenDecl:
+ switch n.Tok {
+ case token.IMPORT:
+ return "import declaration"
+ case token.CONST:
+ return "constant declaration"
+ case token.TYPE:
+ return "type declaration"
+ case token.VAR:
+ return "variable declaration"
+ }
+ case *ast.GoStmt:
+ return "go statement"
+ case *ast.Ident:
+ return "identifier"
+ case *ast.IfStmt:
+ return "if statement"
+ case *ast.ImportSpec:
+ return "import specification"
+ case *ast.IncDecStmt:
+ if n.Tok == token.INC {
+ return "increment statement"
+ }
+ return "decrement statement"
+ case *ast.IndexExpr:
+ return "index expression"
+ case *typeparams.IndexListExpr:
+ return "index list expression"
+ case *ast.InterfaceType:
+ return "interface type"
+ case *ast.KeyValueExpr:
+ return "key/value association"
+ case *ast.LabeledStmt:
+ return "statement label"
+ case *ast.MapType:
+ return "map type"
+ case *ast.Package:
+ return "package"
+ case *ast.ParenExpr:
+ return "parenthesized " + NodeDescription(n.X)
+ case *ast.RangeStmt:
+ return "range loop"
+ case *ast.ReturnStmt:
+ return "return statement"
+ case *ast.SelectStmt:
+ return "select statement"
+ case *ast.SelectorExpr:
+ return "selector"
+ case *ast.SendStmt:
+ return "channel send"
+ case *ast.SliceExpr:
+ return "slice expression"
+ case *ast.StarExpr:
+ return "*-operation" // load/store expr or pointer type
+ case *ast.StructType:
+ return "struct type"
+ case *ast.SwitchStmt:
+ return "switch statement"
+ case *ast.TypeAssertExpr:
+ return "type assertion"
+ case *ast.TypeSpec:
+ return "type specification"
+ case *ast.TypeSwitchStmt:
+ return "type switch"
+ case *ast.UnaryExpr:
+ return fmt.Sprintf("unary %s operation", n.Op)
+ case *ast.ValueSpec:
+ return "value specification"
+
+ }
+ panic(fmt.Sprintf("unexpected node type: %T", n))
+}
diff --git a/vendor/golang.org/x/tools/go/ast/astutil/imports.go b/vendor/golang.org/x/tools/go/ast/astutil/imports.go
new file mode 100644
index 0000000..18d1adb
--- /dev/null
+++ b/vendor/golang.org/x/tools/go/ast/astutil/imports.go
@@ -0,0 +1,485 @@
+// Copyright 2013 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package astutil contains common utilities for working with the Go AST.
+package astutil // import "golang.org/x/tools/go/ast/astutil"
+
+import (
+ "fmt"
+ "go/ast"
+ "go/token"
+ "strconv"
+ "strings"
+)
+
+// AddImport adds the import path to the file f, if absent.
+func AddImport(fset *token.FileSet, f *ast.File, path string) (added bool) {
+ return AddNamedImport(fset, f, "", path)
+}
+
+// AddNamedImport adds the import with the given name and path to the file f, if absent.
+// If name is not empty, it is used to rename the import.
+//
+// For example, calling
+//
+// AddNamedImport(fset, f, "pathpkg", "path")
+//
+// adds
+//
+// import pathpkg "path"
+func AddNamedImport(fset *token.FileSet, f *ast.File, name, path string) (added bool) {
+ if imports(f, name, path) {
+ return false
+ }
+
+ newImport := &ast.ImportSpec{
+ Path: &ast.BasicLit{
+ Kind: token.STRING,
+ Value: strconv.Quote(path),
+ },
+ }
+ if name != "" {
+ newImport.Name = &ast.Ident{Name: name}
+ }
+
+ // Find an import decl to add to.
+ // The goal is to find an existing import
+ // whose import path has the longest shared
+ // prefix with path.
+ var (
+ bestMatch = -1 // length of longest shared prefix
+ lastImport = -1 // index in f.Decls of the file's final import decl
+ impDecl *ast.GenDecl // import decl containing the best match
+ impIndex = -1 // spec index in impDecl containing the best match
+
+ isThirdPartyPath = isThirdParty(path)
+ )
+ for i, decl := range f.Decls {
+ gen, ok := decl.(*ast.GenDecl)
+ if ok && gen.Tok == token.IMPORT {
+ lastImport = i
+ // Do not add to import "C", to avoid disrupting the
+ // association with its doc comment, breaking cgo.
+ if declImports(gen, "C") {
+ continue
+ }
+
+ // Match an empty import decl if that's all that is available.
+ if len(gen.Specs) == 0 && bestMatch == -1 {
+ impDecl = gen
+ }
+
+ // Compute longest shared prefix with imports in this group and find best
+ // matched import spec.
+ // 1. Always prefer import spec with longest shared prefix.
+ // 2. While match length is 0,
+ // - for stdlib package: prefer first import spec.
+ // - for third party package: prefer first third party import spec.
+ // We cannot use last import spec as best match for third party package
+ // because grouped imports are usually placed last by goimports -local
+ // flag.
+ // See issue #19190.
+ seenAnyThirdParty := false
+ for j, spec := range gen.Specs {
+ impspec := spec.(*ast.ImportSpec)
+ p := importPath(impspec)
+ n := matchLen(p, path)
+ if n > bestMatch || (bestMatch == 0 && !seenAnyThirdParty && isThirdPartyPath) {
+ bestMatch = n
+ impDecl = gen
+ impIndex = j
+ }
+ seenAnyThirdParty = seenAnyThirdParty || isThirdParty(p)
+ }
+ }
+ }
+
+ // If no import decl found, add one after the last import.
+ if impDecl == nil {
+ impDecl = &ast.GenDecl{
+ Tok: token.IMPORT,
+ }
+ if lastImport >= 0 {
+ impDecl.TokPos = f.Decls[lastImport].End()
+ } else {
+ // There are no existing imports.
+ // Our new import, preceded by a blank line, goes after the package declaration
+ // and after the comment, if any, that starts on the same line as the
+ // package declaration.
+ impDecl.TokPos = f.Package
+
+ file := fset.File(f.Package)
+ pkgLine := file.Line(f.Package)
+ for _, c := range f.Comments {
+ if file.Line(c.Pos()) > pkgLine {
+ break
+ }
+ // +2 for a blank line
+ impDecl.TokPos = c.End() + 2
+ }
+ }
+ f.Decls = append(f.Decls, nil)
+ copy(f.Decls[lastImport+2:], f.Decls[lastImport+1:])
+ f.Decls[lastImport+1] = impDecl
+ }
+
+ // Insert new import at insertAt.
+ insertAt := 0
+ if impIndex >= 0 {
+ // insert after the found import
+ insertAt = impIndex + 1
+ }
+ impDecl.Specs = append(impDecl.Specs, nil)
+ copy(impDecl.Specs[insertAt+1:], impDecl.Specs[insertAt:])
+ impDecl.Specs[insertAt] = newImport
+ pos := impDecl.Pos()
+ if insertAt > 0 {
+ // If there is a comment after an existing import, preserve the comment
+ // position by adding the new import after the comment.
+ if spec, ok := impDecl.Specs[insertAt-1].(*ast.ImportSpec); ok && spec.Comment != nil {
+ pos = spec.Comment.End()
+ } else {
+ // Assign same position as the previous import,
+ // so that the sorter sees it as being in the same block.
+ pos = impDecl.Specs[insertAt-1].Pos()
+ }
+ }
+ if newImport.Name != nil {
+ newImport.Name.NamePos = pos
+ }
+ newImport.Path.ValuePos = pos
+ newImport.EndPos = pos
+
+ // Clean up parens. impDecl contains at least one spec.
+ if len(impDecl.Specs) == 1 {
+ // Remove unneeded parens.
+ impDecl.Lparen = token.NoPos
+ } else if !impDecl.Lparen.IsValid() {
+ // impDecl needs parens added.
+ impDecl.Lparen = impDecl.Specs[0].Pos()
+ }
+
+ f.Imports = append(f.Imports, newImport)
+
+ if len(f.Decls) <= 1 {
+ return true
+ }
+
+ // Merge all the import declarations into the first one.
+ var first *ast.GenDecl
+ for i := 0; i < len(f.Decls); i++ {
+ decl := f.Decls[i]
+ gen, ok := decl.(*ast.GenDecl)
+ if !ok || gen.Tok != token.IMPORT || declImports(gen, "C") {
+ continue
+ }
+ if first == nil {
+ first = gen
+ continue // Don't touch the first one.
+ }
+ // We now know there is more than one package in this import
+ // declaration. Ensure that it ends up parenthesized.
+ first.Lparen = first.Pos()
+ // Move the imports of the other import declaration to the first one.
+ for _, spec := range gen.Specs {
+ spec.(*ast.ImportSpec).Path.ValuePos = first.Pos()
+ first.Specs = append(first.Specs, spec)
+ }
+ f.Decls = append(f.Decls[:i], f.Decls[i+1:]...)
+ i--
+ }
+
+ return true
+}
+
+func isThirdParty(importPath string) bool {
+ // Third party package import path usually contains "." (".com", ".org", ...)
+ // This logic is taken from golang.org/x/tools/imports package.
+ return strings.Contains(importPath, ".")
+}
+
+// DeleteImport deletes the import path from the file f, if present.
+// If there are duplicate import declarations, all matching ones are deleted.
+func DeleteImport(fset *token.FileSet, f *ast.File, path string) (deleted bool) {
+ return DeleteNamedImport(fset, f, "", path)
+}
+
+// DeleteNamedImport deletes the import with the given name and path from the file f, if present.
+// If there are duplicate import declarations, all matching ones are deleted.
+func DeleteNamedImport(fset *token.FileSet, f *ast.File, name, path string) (deleted bool) {
+ var delspecs []*ast.ImportSpec
+ var delcomments []*ast.CommentGroup
+
+ // Find the import nodes that import path, if any.
+ for i := 0; i < len(f.Decls); i++ {
+ decl := f.Decls[i]
+ gen, ok := decl.(*ast.GenDecl)
+ if !ok || gen.Tok != token.IMPORT {
+ continue
+ }
+ for j := 0; j < len(gen.Specs); j++ {
+ spec := gen.Specs[j]
+ impspec := spec.(*ast.ImportSpec)
+ if importName(impspec) != name || importPath(impspec) != path {
+ continue
+ }
+
+ // We found an import spec that imports path.
+ // Delete it.
+ delspecs = append(delspecs, impspec)
+ deleted = true
+ copy(gen.Specs[j:], gen.Specs[j+1:])
+ gen.Specs = gen.Specs[:len(gen.Specs)-1]
+
+ // If this was the last import spec in this decl,
+ // delete the decl, too.
+ if len(gen.Specs) == 0 {
+ copy(f.Decls[i:], f.Decls[i+1:])
+ f.Decls = f.Decls[:len(f.Decls)-1]
+ i--
+ break
+ } else if len(gen.Specs) == 1 {
+ if impspec.Doc != nil {
+ delcomments = append(delcomments, impspec.Doc)
+ }
+ if impspec.Comment != nil {
+ delcomments = append(delcomments, impspec.Comment)
+ }
+ for _, cg := range f.Comments {
+ // Found comment on the same line as the import spec.
+ if cg.End() < impspec.Pos() && fset.Position(cg.End()).Line == fset.Position(impspec.Pos()).Line {
+ delcomments = append(delcomments, cg)
+ break
+ }
+ }
+
+ spec := gen.Specs[0].(*ast.ImportSpec)
+
+ // Move the documentation right after the import decl.
+ if spec.Doc != nil {
+ for fset.Position(gen.TokPos).Line+1 < fset.Position(spec.Doc.Pos()).Line {
+ fset.File(gen.TokPos).MergeLine(fset.Position(gen.TokPos).Line)
+ }
+ }
+ for _, cg := range f.Comments {
+ if cg.End() < spec.Pos() && fset.Position(cg.End()).Line == fset.Position(spec.Pos()).Line {
+ for fset.Position(gen.TokPos).Line+1 < fset.Position(spec.Pos()).Line {
+ fset.File(gen.TokPos).MergeLine(fset.Position(gen.TokPos).Line)
+ }
+ break
+ }
+ }
+ }
+ if j > 0 {
+ lastImpspec := gen.Specs[j-1].(*ast.ImportSpec)
+ lastLine := fset.PositionFor(lastImpspec.Path.ValuePos, false).Line
+ line := fset.PositionFor(impspec.Path.ValuePos, false).Line
+
+ // We deleted an entry but now there may be
+ // a blank line-sized hole where the import was.
+ if line-lastLine > 1 || !gen.Rparen.IsValid() {
+ // There was a blank line immediately preceding the deleted import,
+ // so there's no need to close the hole. The right parenthesis is
+ // invalid after AddImport to an import statement without parenthesis.
+ // Do nothing.
+ } else if line != fset.File(gen.Rparen).LineCount() {
+ // There was no blank line. Close the hole.
+ fset.File(gen.Rparen).MergeLine(line)
+ }
+ }
+ j--
+ }
+ }
+
+ // Delete imports from f.Imports.
+ for i := 0; i < len(f.Imports); i++ {
+ imp := f.Imports[i]
+ for j, del := range delspecs {
+ if imp == del {
+ copy(f.Imports[i:], f.Imports[i+1:])
+ f.Imports = f.Imports[:len(f.Imports)-1]
+ copy(delspecs[j:], delspecs[j+1:])
+ delspecs = delspecs[:len(delspecs)-1]
+ i--
+ break
+ }
+ }
+ }
+
+ // Delete comments from f.Comments.
+ for i := 0; i < len(f.Comments); i++ {
+ cg := f.Comments[i]
+ for j, del := range delcomments {
+ if cg == del {
+ copy(f.Comments[i:], f.Comments[i+1:])
+ f.Comments = f.Comments[:len(f.Comments)-1]
+ copy(delcomments[j:], delcomments[j+1:])
+ delcomments = delcomments[:len(delcomments)-1]
+ i--
+ break
+ }
+ }
+ }
+
+ if len(delspecs) > 0 {
+ panic(fmt.Sprintf("deleted specs from Decls but not Imports: %v", delspecs))
+ }
+
+ return
+}
+
+// RewriteImport rewrites any import of path oldPath to path newPath.
+func RewriteImport(fset *token.FileSet, f *ast.File, oldPath, newPath string) (rewrote bool) {
+ for _, imp := range f.Imports {
+ if importPath(imp) == oldPath {
+ rewrote = true
+ // record old End, because the default is to compute
+ // it using the length of imp.Path.Value.
+ imp.EndPos = imp.End()
+ imp.Path.Value = strconv.Quote(newPath)
+ }
+ }
+ return
+}
+
+// UsesImport reports whether a given import is used.
+func UsesImport(f *ast.File, path string) (used bool) {
+ spec := importSpec(f, path)
+ if spec == nil {
+ return
+ }
+
+ name := spec.Name.String()
+ switch name {
+ case "":
+ // If the package name is not explicitly specified,
+ // make an educated guess. This is not guaranteed to be correct.
+ lastSlash := strings.LastIndex(path, "/")
+ if lastSlash == -1 {
+ name = path
+ } else {
+ name = path[lastSlash+1:]
+ }
+ case "_", ".":
+ // Not sure if this import is used - err on the side of caution.
+ return true
+ }
+
+ ast.Walk(visitFn(func(n ast.Node) {
+ sel, ok := n.(*ast.SelectorExpr)
+ if ok && isTopName(sel.X, name) {
+ used = true
+ }
+ }), f)
+
+ return
+}
+
+type visitFn func(node ast.Node)
+
+func (fn visitFn) Visit(node ast.Node) ast.Visitor {
+ fn(node)
+ return fn
+}
+
+// imports reports whether f has an import with the specified name and path.
+func imports(f *ast.File, name, path string) bool {
+ for _, s := range f.Imports {
+ if importName(s) == name && importPath(s) == path {
+ return true
+ }
+ }
+ return false
+}
+
+// importSpec returns the import spec if f imports path,
+// or nil otherwise.
+func importSpec(f *ast.File, path string) *ast.ImportSpec {
+ for _, s := range f.Imports {
+ if importPath(s) == path {
+ return s
+ }
+ }
+ return nil
+}
+
+// importName returns the name of s,
+// or "" if the import is not named.
+func importName(s *ast.ImportSpec) string {
+ if s.Name == nil {
+ return ""
+ }
+ return s.Name.Name
+}
+
+// importPath returns the unquoted import path of s,
+// or "" if the path is not properly quoted.
+func importPath(s *ast.ImportSpec) string {
+ t, err := strconv.Unquote(s.Path.Value)
+ if err != nil {
+ return ""
+ }
+ return t
+}
+
+// declImports reports whether gen contains an import of path.
+func declImports(gen *ast.GenDecl, path string) bool {
+ if gen.Tok != token.IMPORT {
+ return false
+ }
+ for _, spec := range gen.Specs {
+ impspec := spec.(*ast.ImportSpec)
+ if importPath(impspec) == path {
+ return true
+ }
+ }
+ return false
+}
+
+// matchLen returns the length of the longest path segment prefix shared by x and y.
+func matchLen(x, y string) int {
+ n := 0
+ for i := 0; i < len(x) && i < len(y) && x[i] == y[i]; i++ {
+ if x[i] == '/' {
+ n++
+ }
+ }
+ return n
+}
+
+// isTopName returns true if n is a top-level unresolved identifier with the given name.
+func isTopName(n ast.Expr, name string) bool {
+ id, ok := n.(*ast.Ident)
+ return ok && id.Name == name && id.Obj == nil
+}
+
+// Imports returns the file imports grouped by paragraph.
+func Imports(fset *token.FileSet, f *ast.File) [][]*ast.ImportSpec {
+ var groups [][]*ast.ImportSpec
+
+ for _, decl := range f.Decls {
+ genDecl, ok := decl.(*ast.GenDecl)
+ if !ok || genDecl.Tok != token.IMPORT {
+ break
+ }
+
+ group := []*ast.ImportSpec{}
+
+ var lastLine int
+ for _, spec := range genDecl.Specs {
+ importSpec := spec.(*ast.ImportSpec)
+ pos := importSpec.Path.ValuePos
+ line := fset.Position(pos).Line
+ if lastLine > 0 && pos > 0 && line-lastLine > 1 {
+ groups = append(groups, group)
+ group = []*ast.ImportSpec{}
+ }
+ group = append(group, importSpec)
+ lastLine = line
+ }
+ groups = append(groups, group)
+ }
+
+ return groups
+}
diff --git a/vendor/golang.org/x/tools/go/ast/astutil/rewrite.go b/vendor/golang.org/x/tools/go/ast/astutil/rewrite.go
new file mode 100644
index 0000000..f430b21
--- /dev/null
+++ b/vendor/golang.org/x/tools/go/ast/astutil/rewrite.go
@@ -0,0 +1,488 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package astutil
+
+import (
+ "fmt"
+ "go/ast"
+ "reflect"
+ "sort"
+
+ "golang.org/x/tools/internal/typeparams"
+)
+
+// An ApplyFunc is invoked by Apply for each node n, even if n is nil,
+// before and/or after the node's children, using a Cursor describing
+// the current node and providing operations on it.
+//
+// The return value of ApplyFunc controls the syntax tree traversal.
+// See Apply for details.
+type ApplyFunc func(*Cursor) bool
+
+// Apply traverses a syntax tree recursively, starting with root,
+// and calling pre and post for each node as described below.
+// Apply returns the syntax tree, possibly modified.
+//
+// If pre is not nil, it is called for each node before the node's
+// children are traversed (pre-order). If pre returns false, no
+// children are traversed, and post is not called for that node.
+//
+// If post is not nil, and a prior call of pre didn't return false,
+// post is called for each node after its children are traversed
+// (post-order). If post returns false, traversal is terminated and
+// Apply returns immediately.
+//
+// Only fields that refer to AST nodes are considered children;
+// i.e., token.Pos, Scopes, Objects, and fields of basic types
+// (strings, etc.) are ignored.
+//
+// Children are traversed in the order in which they appear in the
+// respective node's struct definition. A package's files are
+// traversed in the filenames' alphabetical order.
+func Apply(root ast.Node, pre, post ApplyFunc) (result ast.Node) {
+ parent := &struct{ ast.Node }{root}
+ defer func() {
+ if r := recover(); r != nil && r != abort {
+ panic(r)
+ }
+ result = parent.Node
+ }()
+ a := &application{pre: pre, post: post}
+ a.apply(parent, "Node", nil, root)
+ return
+}
+
+var abort = new(int) // singleton, to signal termination of Apply
+
+// A Cursor describes a node encountered during Apply.
+// Information about the node and its parent is available
+// from the Node, Parent, Name, and Index methods.
+//
+// If p is a variable of type and value of the current parent node
+// c.Parent(), and f is the field identifier with name c.Name(),
+// the following invariants hold:
+//
+// p.f == c.Node() if c.Index() < 0
+// p.f[c.Index()] == c.Node() if c.Index() >= 0
+//
+// The methods Replace, Delete, InsertBefore, and InsertAfter
+// can be used to change the AST without disrupting Apply.
+type Cursor struct {
+ parent ast.Node
+ name string
+ iter *iterator // valid if non-nil
+ node ast.Node
+}
+
+// Node returns the current Node.
+func (c *Cursor) Node() ast.Node { return c.node }
+
+// Parent returns the parent of the current Node.
+func (c *Cursor) Parent() ast.Node { return c.parent }
+
+// Name returns the name of the parent Node field that contains the current Node.
+// If the parent is a *ast.Package and the current Node is a *ast.File, Name returns
+// the filename for the current Node.
+func (c *Cursor) Name() string { return c.name }
+
+// Index reports the index >= 0 of the current Node in the slice of Nodes that
+// contains it, or a value < 0 if the current Node is not part of a slice.
+// The index of the current node changes if InsertBefore is called while
+// processing the current node.
+func (c *Cursor) Index() int {
+ if c.iter != nil {
+ return c.iter.index
+ }
+ return -1
+}
+
+// field returns the current node's parent field value.
+func (c *Cursor) field() reflect.Value {
+ return reflect.Indirect(reflect.ValueOf(c.parent)).FieldByName(c.name)
+}
+
+// Replace replaces the current Node with n.
+// The replacement node is not walked by Apply.
+func (c *Cursor) Replace(n ast.Node) {
+ if _, ok := c.node.(*ast.File); ok {
+ file, ok := n.(*ast.File)
+ if !ok {
+ panic("attempt to replace *ast.File with non-*ast.File")
+ }
+ c.parent.(*ast.Package).Files[c.name] = file
+ return
+ }
+
+ v := c.field()
+ if i := c.Index(); i >= 0 {
+ v = v.Index(i)
+ }
+ v.Set(reflect.ValueOf(n))
+}
+
+// Delete deletes the current Node from its containing slice.
+// If the current Node is not part of a slice, Delete panics.
+// As a special case, if the current node is a package file,
+// Delete removes it from the package's Files map.
+func (c *Cursor) Delete() {
+ if _, ok := c.node.(*ast.File); ok {
+ delete(c.parent.(*ast.Package).Files, c.name)
+ return
+ }
+
+ i := c.Index()
+ if i < 0 {
+ panic("Delete node not contained in slice")
+ }
+ v := c.field()
+ l := v.Len()
+ reflect.Copy(v.Slice(i, l), v.Slice(i+1, l))
+ v.Index(l - 1).Set(reflect.Zero(v.Type().Elem()))
+ v.SetLen(l - 1)
+ c.iter.step--
+}
+
+// InsertAfter inserts n after the current Node in its containing slice.
+// If the current Node is not part of a slice, InsertAfter panics.
+// Apply does not walk n.
+func (c *Cursor) InsertAfter(n ast.Node) {
+ i := c.Index()
+ if i < 0 {
+ panic("InsertAfter node not contained in slice")
+ }
+ v := c.field()
+ v.Set(reflect.Append(v, reflect.Zero(v.Type().Elem())))
+ l := v.Len()
+ reflect.Copy(v.Slice(i+2, l), v.Slice(i+1, l))
+ v.Index(i + 1).Set(reflect.ValueOf(n))
+ c.iter.step++
+}
+
+// InsertBefore inserts n before the current Node in its containing slice.
+// If the current Node is not part of a slice, InsertBefore panics.
+// Apply will not walk n.
+func (c *Cursor) InsertBefore(n ast.Node) {
+ i := c.Index()
+ if i < 0 {
+ panic("InsertBefore node not contained in slice")
+ }
+ v := c.field()
+ v.Set(reflect.Append(v, reflect.Zero(v.Type().Elem())))
+ l := v.Len()
+ reflect.Copy(v.Slice(i+1, l), v.Slice(i, l))
+ v.Index(i).Set(reflect.ValueOf(n))
+ c.iter.index++
+}
+
+// application carries all the shared data so we can pass it around cheaply.
+type application struct {
+ pre, post ApplyFunc
+ cursor Cursor
+ iter iterator
+}
+
+func (a *application) apply(parent ast.Node, name string, iter *iterator, n ast.Node) {
+ // convert typed nil into untyped nil
+ if v := reflect.ValueOf(n); v.Kind() == reflect.Ptr && v.IsNil() {
+ n = nil
+ }
+
+ // avoid heap-allocating a new cursor for each apply call; reuse a.cursor instead
+ saved := a.cursor
+ a.cursor.parent = parent
+ a.cursor.name = name
+ a.cursor.iter = iter
+ a.cursor.node = n
+
+ if a.pre != nil && !a.pre(&a.cursor) {
+ a.cursor = saved
+ return
+ }
+
+ // walk children
+ // (the order of the cases matches the order of the corresponding node types in go/ast)
+ switch n := n.(type) {
+ case nil:
+ // nothing to do
+
+ // Comments and fields
+ case *ast.Comment:
+ // nothing to do
+
+ case *ast.CommentGroup:
+ if n != nil {
+ a.applyList(n, "List")
+ }
+
+ case *ast.Field:
+ a.apply(n, "Doc", nil, n.Doc)
+ a.applyList(n, "Names")
+ a.apply(n, "Type", nil, n.Type)
+ a.apply(n, "Tag", nil, n.Tag)
+ a.apply(n, "Comment", nil, n.Comment)
+
+ case *ast.FieldList:
+ a.applyList(n, "List")
+
+ // Expressions
+ case *ast.BadExpr, *ast.Ident, *ast.BasicLit:
+ // nothing to do
+
+ case *ast.Ellipsis:
+ a.apply(n, "Elt", nil, n.Elt)
+
+ case *ast.FuncLit:
+ a.apply(n, "Type", nil, n.Type)
+ a.apply(n, "Body", nil, n.Body)
+
+ case *ast.CompositeLit:
+ a.apply(n, "Type", nil, n.Type)
+ a.applyList(n, "Elts")
+
+ case *ast.ParenExpr:
+ a.apply(n, "X", nil, n.X)
+
+ case *ast.SelectorExpr:
+ a.apply(n, "X", nil, n.X)
+ a.apply(n, "Sel", nil, n.Sel)
+
+ case *ast.IndexExpr:
+ a.apply(n, "X", nil, n.X)
+ a.apply(n, "Index", nil, n.Index)
+
+ case *typeparams.IndexListExpr:
+ a.apply(n, "X", nil, n.X)
+ a.applyList(n, "Indices")
+
+ case *ast.SliceExpr:
+ a.apply(n, "X", nil, n.X)
+ a.apply(n, "Low", nil, n.Low)
+ a.apply(n, "High", nil, n.High)
+ a.apply(n, "Max", nil, n.Max)
+
+ case *ast.TypeAssertExpr:
+ a.apply(n, "X", nil, n.X)
+ a.apply(n, "Type", nil, n.Type)
+
+ case *ast.CallExpr:
+ a.apply(n, "Fun", nil, n.Fun)
+ a.applyList(n, "Args")
+
+ case *ast.StarExpr:
+ a.apply(n, "X", nil, n.X)
+
+ case *ast.UnaryExpr:
+ a.apply(n, "X", nil, n.X)
+
+ case *ast.BinaryExpr:
+ a.apply(n, "X", nil, n.X)
+ a.apply(n, "Y", nil, n.Y)
+
+ case *ast.KeyValueExpr:
+ a.apply(n, "Key", nil, n.Key)
+ a.apply(n, "Value", nil, n.Value)
+
+ // Types
+ case *ast.ArrayType:
+ a.apply(n, "Len", nil, n.Len)
+ a.apply(n, "Elt", nil, n.Elt)
+
+ case *ast.StructType:
+ a.apply(n, "Fields", nil, n.Fields)
+
+ case *ast.FuncType:
+ if tparams := typeparams.ForFuncType(n); tparams != nil {
+ a.apply(n, "TypeParams", nil, tparams)
+ }
+ a.apply(n, "Params", nil, n.Params)
+ a.apply(n, "Results", nil, n.Results)
+
+ case *ast.InterfaceType:
+ a.apply(n, "Methods", nil, n.Methods)
+
+ case *ast.MapType:
+ a.apply(n, "Key", nil, n.Key)
+ a.apply(n, "Value", nil, n.Value)
+
+ case *ast.ChanType:
+ a.apply(n, "Value", nil, n.Value)
+
+ // Statements
+ case *ast.BadStmt:
+ // nothing to do
+
+ case *ast.DeclStmt:
+ a.apply(n, "Decl", nil, n.Decl)
+
+ case *ast.EmptyStmt:
+ // nothing to do
+
+ case *ast.LabeledStmt:
+ a.apply(n, "Label", nil, n.Label)
+ a.apply(n, "Stmt", nil, n.Stmt)
+
+ case *ast.ExprStmt:
+ a.apply(n, "X", nil, n.X)
+
+ case *ast.SendStmt:
+ a.apply(n, "Chan", nil, n.Chan)
+ a.apply(n, "Value", nil, n.Value)
+
+ case *ast.IncDecStmt:
+ a.apply(n, "X", nil, n.X)
+
+ case *ast.AssignStmt:
+ a.applyList(n, "Lhs")
+ a.applyList(n, "Rhs")
+
+ case *ast.GoStmt:
+ a.apply(n, "Call", nil, n.Call)
+
+ case *ast.DeferStmt:
+ a.apply(n, "Call", nil, n.Call)
+
+ case *ast.ReturnStmt:
+ a.applyList(n, "Results")
+
+ case *ast.BranchStmt:
+ a.apply(n, "Label", nil, n.Label)
+
+ case *ast.BlockStmt:
+ a.applyList(n, "List")
+
+ case *ast.IfStmt:
+ a.apply(n, "Init", nil, n.Init)
+ a.apply(n, "Cond", nil, n.Cond)
+ a.apply(n, "Body", nil, n.Body)
+ a.apply(n, "Else", nil, n.Else)
+
+ case *ast.CaseClause:
+ a.applyList(n, "List")
+ a.applyList(n, "Body")
+
+ case *ast.SwitchStmt:
+ a.apply(n, "Init", nil, n.Init)
+ a.apply(n, "Tag", nil, n.Tag)
+ a.apply(n, "Body", nil, n.Body)
+
+ case *ast.TypeSwitchStmt:
+ a.apply(n, "Init", nil, n.Init)
+ a.apply(n, "Assign", nil, n.Assign)
+ a.apply(n, "Body", nil, n.Body)
+
+ case *ast.CommClause:
+ a.apply(n, "Comm", nil, n.Comm)
+ a.applyList(n, "Body")
+
+ case *ast.SelectStmt:
+ a.apply(n, "Body", nil, n.Body)
+
+ case *ast.ForStmt:
+ a.apply(n, "Init", nil, n.Init)
+ a.apply(n, "Cond", nil, n.Cond)
+ a.apply(n, "Post", nil, n.Post)
+ a.apply(n, "Body", nil, n.Body)
+
+ case *ast.RangeStmt:
+ a.apply(n, "Key", nil, n.Key)
+ a.apply(n, "Value", nil, n.Value)
+ a.apply(n, "X", nil, n.X)
+ a.apply(n, "Body", nil, n.Body)
+
+ // Declarations
+ case *ast.ImportSpec:
+ a.apply(n, "Doc", nil, n.Doc)
+ a.apply(n, "Name", nil, n.Name)
+ a.apply(n, "Path", nil, n.Path)
+ a.apply(n, "Comment", nil, n.Comment)
+
+ case *ast.ValueSpec:
+ a.apply(n, "Doc", nil, n.Doc)
+ a.applyList(n, "Names")
+ a.apply(n, "Type", nil, n.Type)
+ a.applyList(n, "Values")
+ a.apply(n, "Comment", nil, n.Comment)
+
+ case *ast.TypeSpec:
+ a.apply(n, "Doc", nil, n.Doc)
+ a.apply(n, "Name", nil, n.Name)
+ if tparams := typeparams.ForTypeSpec(n); tparams != nil {
+ a.apply(n, "TypeParams", nil, tparams)
+ }
+ a.apply(n, "Type", nil, n.Type)
+ a.apply(n, "Comment", nil, n.Comment)
+
+ case *ast.BadDecl:
+ // nothing to do
+
+ case *ast.GenDecl:
+ a.apply(n, "Doc", nil, n.Doc)
+ a.applyList(n, "Specs")
+
+ case *ast.FuncDecl:
+ a.apply(n, "Doc", nil, n.Doc)
+ a.apply(n, "Recv", nil, n.Recv)
+ a.apply(n, "Name", nil, n.Name)
+ a.apply(n, "Type", nil, n.Type)
+ a.apply(n, "Body", nil, n.Body)
+
+ // Files and packages
+ case *ast.File:
+ a.apply(n, "Doc", nil, n.Doc)
+ a.apply(n, "Name", nil, n.Name)
+ a.applyList(n, "Decls")
+ // Don't walk n.Comments; they have either been walked already if
+ // they are Doc comments, or they can be easily walked explicitly.
+
+ case *ast.Package:
+ // collect and sort names for reproducible behavior
+ var names []string
+ for name := range n.Files {
+ names = append(names, name)
+ }
+ sort.Strings(names)
+ for _, name := range names {
+ a.apply(n, name, nil, n.Files[name])
+ }
+
+ default:
+ panic(fmt.Sprintf("Apply: unexpected node type %T", n))
+ }
+
+ if a.post != nil && !a.post(&a.cursor) {
+ panic(abort)
+ }
+
+ a.cursor = saved
+}
+
+// An iterator controls iteration over a slice of nodes.
+type iterator struct {
+ index, step int
+}
+
+func (a *application) applyList(parent ast.Node, name string) {
+ // avoid heap-allocating a new iterator for each applyList call; reuse a.iter instead
+ saved := a.iter
+ a.iter.index = 0
+ for {
+ // must reload parent.name each time, since cursor modifications might change it
+ v := reflect.Indirect(reflect.ValueOf(parent)).FieldByName(name)
+ if a.iter.index >= v.Len() {
+ break
+ }
+
+ // element x may be nil in a bad AST - be cautious
+ var x ast.Node
+ if e := v.Index(a.iter.index); e.IsValid() {
+ x = e.Interface().(ast.Node)
+ }
+
+ a.iter.step = 1
+ a.apply(parent, name, &a.iter, x)
+ a.iter.index += a.iter.step
+ }
+ a.iter = saved
+}
diff --git a/vendor/golang.org/x/tools/go/ast/astutil/util.go b/vendor/golang.org/x/tools/go/ast/astutil/util.go
new file mode 100644
index 0000000..919d530
--- /dev/null
+++ b/vendor/golang.org/x/tools/go/ast/astutil/util.go
@@ -0,0 +1,18 @@
+// Copyright 2015 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package astutil
+
+import "go/ast"
+
+// Unparen returns e with any enclosing parentheses stripped.
+func Unparen(e ast.Expr) ast.Expr {
+ for {
+ p, ok := e.(*ast.ParenExpr)
+ if !ok {
+ return e
+ }
+ e = p.X
+ }
+}
diff --git a/vendor/golang.org/x/tools/go/types/typeutil/callee.go b/vendor/golang.org/x/tools/go/types/typeutil/callee.go
new file mode 100644
index 0000000..90b3ab0
--- /dev/null
+++ b/vendor/golang.org/x/tools/go/types/typeutil/callee.go
@@ -0,0 +1,69 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package typeutil
+
+import (
+ "go/ast"
+ "go/types"
+
+ "golang.org/x/tools/go/ast/astutil"
+ "golang.org/x/tools/internal/typeparams"
+)
+
+// Callee returns the named target of a function call, if any:
+// a function, method, builtin, or variable.
+//
+// Functions and methods may potentially have type parameters.
+func Callee(info *types.Info, call *ast.CallExpr) types.Object {
+ fun := astutil.Unparen(call.Fun)
+
+ // Look through type instantiation if necessary.
+ isInstance := false
+ switch fun.(type) {
+ case *ast.IndexExpr, *typeparams.IndexListExpr:
+ // When extracting the callee from an *IndexExpr, we need to check that
+ // it is a *types.Func and not a *types.Var.
+ // Example: Don't match a slice m within the expression `m[0]()`.
+ isInstance = true
+ fun, _, _, _ = typeparams.UnpackIndexExpr(fun)
+ }
+
+ var obj types.Object
+ switch fun := fun.(type) {
+ case *ast.Ident:
+ obj = info.Uses[fun] // type, var, builtin, or declared func
+ case *ast.SelectorExpr:
+ if sel, ok := info.Selections[fun]; ok {
+ obj = sel.Obj() // method or field
+ } else {
+ obj = info.Uses[fun.Sel] // qualified identifier?
+ }
+ }
+ if _, ok := obj.(*types.TypeName); ok {
+ return nil // T(x) is a conversion, not a call
+ }
+ // A Func is required to match instantiations.
+ if _, ok := obj.(*types.Func); isInstance && !ok {
+ return nil // Was not a Func.
+ }
+ return obj
+}
+
+// StaticCallee returns the target (function or method) of a static function
+// call, if any. It returns nil for calls to builtins.
+//
+// Note: for calls of instantiated functions and methods, StaticCallee returns
+// the corresponding generic function or method on the generic type.
+func StaticCallee(info *types.Info, call *ast.CallExpr) *types.Func {
+ if f, ok := Callee(info, call).(*types.Func); ok && !interfaceMethod(f) {
+ return f
+ }
+ return nil
+}
+
+func interfaceMethod(f *types.Func) bool {
+ recv := f.Type().(*types.Signature).Recv()
+ return recv != nil && types.IsInterface(recv.Type())
+}
diff --git a/vendor/golang.org/x/tools/go/types/typeutil/imports.go b/vendor/golang.org/x/tools/go/types/typeutil/imports.go
new file mode 100644
index 0000000..b81ce0c
--- /dev/null
+++ b/vendor/golang.org/x/tools/go/types/typeutil/imports.go
@@ -0,0 +1,30 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package typeutil
+
+import "go/types"
+
+// Dependencies returns all dependencies of the specified packages.
+//
+// Dependent packages appear in topological order: if package P imports
+// package Q, Q appears earlier than P in the result.
+// The algorithm follows import statements in the order they
+// appear in the source code, so the result is a total order.
+func Dependencies(pkgs ...*types.Package) []*types.Package {
+ var result []*types.Package
+ seen := make(map[*types.Package]bool)
+ var visit func(pkgs []*types.Package)
+ visit = func(pkgs []*types.Package) {
+ for _, p := range pkgs {
+ if !seen[p] {
+ seen[p] = true
+ visit(p.Imports())
+ result = append(result, p)
+ }
+ }
+ }
+ visit(pkgs)
+ return result
+}
diff --git a/vendor/golang.org/x/tools/go/types/typeutil/map.go b/vendor/golang.org/x/tools/go/types/typeutil/map.go
new file mode 100644
index 0000000..7bd2fdb
--- /dev/null
+++ b/vendor/golang.org/x/tools/go/types/typeutil/map.go
@@ -0,0 +1,511 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Package typeutil defines various utilities for types, such as Map,
+// a mapping from types.Type to interface{} values.
+package typeutil // import "golang.org/x/tools/go/types/typeutil"
+
+import (
+ "bytes"
+ "fmt"
+ "go/types"
+ "reflect"
+
+ "golang.org/x/tools/internal/typeparams"
+)
+
+// Map is a hash-table-based mapping from types (types.Type) to
+// arbitrary interface{} values. The concrete types that implement
+// the Type interface are pointers. Since they are not canonicalized,
+// == cannot be used to check for equivalence, and thus we cannot
+// simply use a Go map.
+//
+// Just as with map[K]V, a nil *Map is a valid empty map.
+//
+// Not thread-safe.
+type Map struct {
+ hasher Hasher // shared by many Maps
+ table map[uint32][]entry // maps hash to bucket; entry.key==nil means unused
+ length int // number of map entries
+}
+
+// entry is an entry (key/value association) in a hash bucket.
+type entry struct {
+ key types.Type
+ value interface{}
+}
+
+// SetHasher sets the hasher used by Map.
+//
+// All Hashers are functionally equivalent but contain internal state
+// used to cache the results of hashing previously seen types.
+//
+// A single Hasher created by MakeHasher() may be shared among many
+// Maps. This is recommended if the instances have many keys in
+// common, as it will amortize the cost of hash computation.
+//
+// A Hasher may grow without bound as new types are seen. Even when a
+// type is deleted from the map, the Hasher never shrinks, since other
+// types in the map may reference the deleted type indirectly.
+//
+// Hashers are not thread-safe, and read-only operations such as
+// Map.Lookup require updates to the hasher, so a full Mutex lock (not a
+// read-lock) is require around all Map operations if a shared
+// hasher is accessed from multiple threads.
+//
+// If SetHasher is not called, the Map will create a private hasher at
+// the first call to Insert.
+func (m *Map) SetHasher(hasher Hasher) {
+ m.hasher = hasher
+}
+
+// Delete removes the entry with the given key, if any.
+// It returns true if the entry was found.
+func (m *Map) Delete(key types.Type) bool {
+ if m != nil && m.table != nil {
+ hash := m.hasher.Hash(key)
+ bucket := m.table[hash]
+ for i, e := range bucket {
+ if e.key != nil && types.Identical(key, e.key) {
+ // We can't compact the bucket as it
+ // would disturb iterators.
+ bucket[i] = entry{}
+ m.length--
+ return true
+ }
+ }
+ }
+ return false
+}
+
+// At returns the map entry for the given key.
+// The result is nil if the entry is not present.
+func (m *Map) At(key types.Type) interface{} {
+ if m != nil && m.table != nil {
+ for _, e := range m.table[m.hasher.Hash(key)] {
+ if e.key != nil && types.Identical(key, e.key) {
+ return e.value
+ }
+ }
+ }
+ return nil
+}
+
+// Set sets the map entry for key to val,
+// and returns the previous entry, if any.
+func (m *Map) Set(key types.Type, value interface{}) (prev interface{}) {
+ if m.table != nil {
+ hash := m.hasher.Hash(key)
+ bucket := m.table[hash]
+ var hole *entry
+ for i, e := range bucket {
+ if e.key == nil {
+ hole = &bucket[i]
+ } else if types.Identical(key, e.key) {
+ prev = e.value
+ bucket[i].value = value
+ return
+ }
+ }
+
+ if hole != nil {
+ *hole = entry{key, value} // overwrite deleted entry
+ } else {
+ m.table[hash] = append(bucket, entry{key, value})
+ }
+ } else {
+ if m.hasher.memo == nil {
+ m.hasher = MakeHasher()
+ }
+ hash := m.hasher.Hash(key)
+ m.table = map[uint32][]entry{hash: {entry{key, value}}}
+ }
+
+ m.length++
+ return
+}
+
+// Len returns the number of map entries.
+func (m *Map) Len() int {
+ if m != nil {
+ return m.length
+ }
+ return 0
+}
+
+// Iterate calls function f on each entry in the map in unspecified order.
+//
+// If f should mutate the map, Iterate provides the same guarantees as
+// Go maps: if f deletes a map entry that Iterate has not yet reached,
+// f will not be invoked for it, but if f inserts a map entry that
+// Iterate has not yet reached, whether or not f will be invoked for
+// it is unspecified.
+func (m *Map) Iterate(f func(key types.Type, value interface{})) {
+ if m != nil {
+ for _, bucket := range m.table {
+ for _, e := range bucket {
+ if e.key != nil {
+ f(e.key, e.value)
+ }
+ }
+ }
+ }
+}
+
+// Keys returns a new slice containing the set of map keys.
+// The order is unspecified.
+func (m *Map) Keys() []types.Type {
+ keys := make([]types.Type, 0, m.Len())
+ m.Iterate(func(key types.Type, _ interface{}) {
+ keys = append(keys, key)
+ })
+ return keys
+}
+
+func (m *Map) toString(values bool) string {
+ if m == nil {
+ return "{}"
+ }
+ var buf bytes.Buffer
+ fmt.Fprint(&buf, "{")
+ sep := ""
+ m.Iterate(func(key types.Type, value interface{}) {
+ fmt.Fprint(&buf, sep)
+ sep = ", "
+ fmt.Fprint(&buf, key)
+ if values {
+ fmt.Fprintf(&buf, ": %q", value)
+ }
+ })
+ fmt.Fprint(&buf, "}")
+ return buf.String()
+}
+
+// String returns a string representation of the map's entries.
+// Values are printed using fmt.Sprintf("%v", v).
+// Order is unspecified.
+func (m *Map) String() string {
+ return m.toString(true)
+}
+
+// KeysString returns a string representation of the map's key set.
+// Order is unspecified.
+func (m *Map) KeysString() string {
+ return m.toString(false)
+}
+
+////////////////////////////////////////////////////////////////////////
+// Hasher
+
+// A Hasher maps each type to its hash value.
+// For efficiency, a hasher uses memoization; thus its memory
+// footprint grows monotonically over time.
+// Hashers are not thread-safe.
+// Hashers have reference semantics.
+// Call MakeHasher to create a Hasher.
+type Hasher struct {
+ memo map[types.Type]uint32
+
+ // ptrMap records pointer identity.
+ ptrMap map[interface{}]uint32
+
+ // sigTParams holds type parameters from the signature being hashed.
+ // Signatures are considered identical modulo renaming of type parameters, so
+ // within the scope of a signature type the identity of the signature's type
+ // parameters is just their index.
+ //
+ // Since the language does not currently support referring to uninstantiated
+ // generic types or functions, and instantiated signatures do not have type
+ // parameter lists, we should never encounter a second non-empty type
+ // parameter list when hashing a generic signature.
+ sigTParams *typeparams.TypeParamList
+}
+
+// MakeHasher returns a new Hasher instance.
+func MakeHasher() Hasher {
+ return Hasher{
+ memo: make(map[types.Type]uint32),
+ ptrMap: make(map[interface{}]uint32),
+ sigTParams: nil,
+ }
+}
+
+// Hash computes a hash value for the given type t such that
+// Identical(t, t') => Hash(t) == Hash(t').
+func (h Hasher) Hash(t types.Type) uint32 {
+ hash, ok := h.memo[t]
+ if !ok {
+ hash = h.hashFor(t)
+ h.memo[t] = hash
+ }
+ return hash
+}
+
+// hashString computes the Fowler–Noll–Vo hash of s.
+func hashString(s string) uint32 {
+ var h uint32
+ for i := 0; i < len(s); i++ {
+ h ^= uint32(s[i])
+ h *= 16777619
+ }
+ return h
+}
+
+// hashFor computes the hash of t.
+func (h Hasher) hashFor(t types.Type) uint32 {
+ // See Identical for rationale.
+ switch t := t.(type) {
+ case *types.Basic:
+ return uint32(t.Kind())
+
+ case *types.Array:
+ return 9043 + 2*uint32(t.Len()) + 3*h.Hash(t.Elem())
+
+ case *types.Slice:
+ return 9049 + 2*h.Hash(t.Elem())
+
+ case *types.Struct:
+ var hash uint32 = 9059
+ for i, n := 0, t.NumFields(); i < n; i++ {
+ f := t.Field(i)
+ if f.Anonymous() {
+ hash += 8861
+ }
+ hash += hashString(t.Tag(i))
+ hash += hashString(f.Name()) // (ignore f.Pkg)
+ hash += h.Hash(f.Type())
+ }
+ return hash
+
+ case *types.Pointer:
+ return 9067 + 2*h.Hash(t.Elem())
+
+ case *types.Signature:
+ var hash uint32 = 9091
+ if t.Variadic() {
+ hash *= 8863
+ }
+
+ // Use a separate hasher for types inside of the signature, where type
+ // parameter identity is modified to be (index, constraint). We must use a
+ // new memo for this hasher as type identity may be affected by this
+ // masking. For example, in func[T any](*T), the identity of *T depends on
+ // whether we are mapping the argument in isolation, or recursively as part
+ // of hashing the signature.
+ //
+ // We should never encounter a generic signature while hashing another
+ // generic signature, but defensively set sigTParams only if h.mask is
+ // unset.
+ tparams := typeparams.ForSignature(t)
+ if h.sigTParams == nil && tparams.Len() != 0 {
+ h = Hasher{
+ // There may be something more efficient than discarding the existing
+ // memo, but it would require detecting whether types are 'tainted' by
+ // references to type parameters.
+ memo: make(map[types.Type]uint32),
+ // Re-using ptrMap ensures that pointer identity is preserved in this
+ // hasher.
+ ptrMap: h.ptrMap,
+ sigTParams: tparams,
+ }
+ }
+
+ for i := 0; i < tparams.Len(); i++ {
+ tparam := tparams.At(i)
+ hash += 7 * h.Hash(tparam.Constraint())
+ }
+
+ return hash + 3*h.hashTuple(t.Params()) + 5*h.hashTuple(t.Results())
+
+ case *typeparams.Union:
+ return h.hashUnion(t)
+
+ case *types.Interface:
+ // Interfaces are identical if they have the same set of methods, with
+ // identical names and types, and they have the same set of type
+ // restrictions. See go/types.identical for more details.
+ var hash uint32 = 9103
+
+ // Hash methods.
+ for i, n := 0, t.NumMethods(); i < n; i++ {
+ // Method order is not significant.
+ // Ignore m.Pkg().
+ m := t.Method(i)
+ // Use shallow hash on method signature to
+ // avoid anonymous interface cycles.
+ hash += 3*hashString(m.Name()) + 5*h.shallowHash(m.Type())
+ }
+
+ // Hash type restrictions.
+ terms, err := typeparams.InterfaceTermSet(t)
+ // if err != nil t has invalid type restrictions.
+ if err == nil {
+ hash += h.hashTermSet(terms)
+ }
+
+ return hash
+
+ case *types.Map:
+ return 9109 + 2*h.Hash(t.Key()) + 3*h.Hash(t.Elem())
+
+ case *types.Chan:
+ return 9127 + 2*uint32(t.Dir()) + 3*h.Hash(t.Elem())
+
+ case *types.Named:
+ hash := h.hashPtr(t.Obj())
+ targs := typeparams.NamedTypeArgs(t)
+ for i := 0; i < targs.Len(); i++ {
+ targ := targs.At(i)
+ hash += 2 * h.Hash(targ)
+ }
+ return hash
+
+ case *typeparams.TypeParam:
+ return h.hashTypeParam(t)
+
+ case *types.Tuple:
+ return h.hashTuple(t)
+ }
+
+ panic(fmt.Sprintf("%T: %v", t, t))
+}
+
+func (h Hasher) hashTuple(tuple *types.Tuple) uint32 {
+ // See go/types.identicalTypes for rationale.
+ n := tuple.Len()
+ hash := 9137 + 2*uint32(n)
+ for i := 0; i < n; i++ {
+ hash += 3 * h.Hash(tuple.At(i).Type())
+ }
+ return hash
+}
+
+func (h Hasher) hashUnion(t *typeparams.Union) uint32 {
+ // Hash type restrictions.
+ terms, err := typeparams.UnionTermSet(t)
+ // if err != nil t has invalid type restrictions. Fall back on a non-zero
+ // hash.
+ if err != nil {
+ return 9151
+ }
+ return h.hashTermSet(terms)
+}
+
+func (h Hasher) hashTermSet(terms []*typeparams.Term) uint32 {
+ hash := 9157 + 2*uint32(len(terms))
+ for _, term := range terms {
+ // term order is not significant.
+ termHash := h.Hash(term.Type())
+ if term.Tilde() {
+ termHash *= 9161
+ }
+ hash += 3 * termHash
+ }
+ return hash
+}
+
+// hashTypeParam returns a hash of the type parameter t, with a hash value
+// depending on whether t is contained in h.sigTParams.
+//
+// If h.sigTParams is set and contains t, then we are in the process of hashing
+// a signature, and the hash value of t must depend only on t's index and
+// constraint: signatures are considered identical modulo type parameter
+// renaming. To avoid infinite recursion, we only hash the type parameter
+// index, and rely on types.Identical to handle signatures where constraints
+// are not identical.
+//
+// Otherwise the hash of t depends only on t's pointer identity.
+func (h Hasher) hashTypeParam(t *typeparams.TypeParam) uint32 {
+ if h.sigTParams != nil {
+ i := t.Index()
+ if i >= 0 && i < h.sigTParams.Len() && t == h.sigTParams.At(i) {
+ return 9173 + 3*uint32(i)
+ }
+ }
+ return h.hashPtr(t.Obj())
+}
+
+// hashPtr hashes the pointer identity of ptr. It uses h.ptrMap to ensure that
+// pointers values are not dependent on the GC.
+func (h Hasher) hashPtr(ptr interface{}) uint32 {
+ if hash, ok := h.ptrMap[ptr]; ok {
+ return hash
+ }
+ hash := uint32(reflect.ValueOf(ptr).Pointer())
+ h.ptrMap[ptr] = hash
+ return hash
+}
+
+// shallowHash computes a hash of t without looking at any of its
+// element Types, to avoid potential anonymous cycles in the types of
+// interface methods.
+//
+// When an unnamed non-empty interface type appears anywhere among the
+// arguments or results of an interface method, there is a potential
+// for endless recursion. Consider:
+//
+// type X interface { m() []*interface { X } }
+//
+// The problem is that the Methods of the interface in m's result type
+// include m itself; there is no mention of the named type X that
+// might help us break the cycle.
+// (See comment in go/types.identical, case *Interface, for more.)
+func (h Hasher) shallowHash(t types.Type) uint32 {
+ // t is the type of an interface method (Signature),
+ // its params or results (Tuples), or their immediate
+ // elements (mostly Slice, Pointer, Basic, Named),
+ // so there's no need to optimize anything else.
+ switch t := t.(type) {
+ case *types.Signature:
+ var hash uint32 = 604171
+ if t.Variadic() {
+ hash *= 971767
+ }
+ // The Signature/Tuple recursion is always finite
+ // and invariably shallow.
+ return hash + 1062599*h.shallowHash(t.Params()) + 1282529*h.shallowHash(t.Results())
+
+ case *types.Tuple:
+ n := t.Len()
+ hash := 9137 + 2*uint32(n)
+ for i := 0; i < n; i++ {
+ hash += 53471161 * h.shallowHash(t.At(i).Type())
+ }
+ return hash
+
+ case *types.Basic:
+ return 45212177 * uint32(t.Kind())
+
+ case *types.Array:
+ return 1524181 + 2*uint32(t.Len())
+
+ case *types.Slice:
+ return 2690201
+
+ case *types.Struct:
+ return 3326489
+
+ case *types.Pointer:
+ return 4393139
+
+ case *typeparams.Union:
+ return 562448657
+
+ case *types.Interface:
+ return 2124679 // no recursion here
+
+ case *types.Map:
+ return 9109
+
+ case *types.Chan:
+ return 9127
+
+ case *types.Named:
+ return h.hashPtr(t.Obj())
+
+ case *typeparams.TypeParam:
+ return h.hashPtr(t.Obj())
+ }
+ panic(fmt.Sprintf("shallowHash: %T: %v", t, t))
+}
diff --git a/vendor/golang.org/x/tools/go/types/typeutil/methodsetcache.go b/vendor/golang.org/x/tools/go/types/typeutil/methodsetcache.go
new file mode 100644
index 0000000..a5d9310
--- /dev/null
+++ b/vendor/golang.org/x/tools/go/types/typeutil/methodsetcache.go
@@ -0,0 +1,71 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file implements a cache of method sets.
+
+package typeutil
+
+import (
+ "go/types"
+ "sync"
+)
+
+// A MethodSetCache records the method set of each type T for which
+// MethodSet(T) is called so that repeat queries are fast.
+// The zero value is a ready-to-use cache instance.
+type MethodSetCache struct {
+ mu sync.Mutex
+ named map[*types.Named]struct{ value, pointer *types.MethodSet } // method sets for named N and *N
+ others map[types.Type]*types.MethodSet // all other types
+}
+
+// MethodSet returns the method set of type T. It is thread-safe.
+//
+// If cache is nil, this function is equivalent to types.NewMethodSet(T).
+// Utility functions can thus expose an optional *MethodSetCache
+// parameter to clients that care about performance.
+func (cache *MethodSetCache) MethodSet(T types.Type) *types.MethodSet {
+ if cache == nil {
+ return types.NewMethodSet(T)
+ }
+ cache.mu.Lock()
+ defer cache.mu.Unlock()
+
+ switch T := T.(type) {
+ case *types.Named:
+ return cache.lookupNamed(T).value
+
+ case *types.Pointer:
+ if N, ok := T.Elem().(*types.Named); ok {
+ return cache.lookupNamed(N).pointer
+ }
+ }
+
+ // all other types
+ // (The map uses pointer equivalence, not type identity.)
+ mset := cache.others[T]
+ if mset == nil {
+ mset = types.NewMethodSet(T)
+ if cache.others == nil {
+ cache.others = make(map[types.Type]*types.MethodSet)
+ }
+ cache.others[T] = mset
+ }
+ return mset
+}
+
+func (cache *MethodSetCache) lookupNamed(named *types.Named) struct{ value, pointer *types.MethodSet } {
+ if cache.named == nil {
+ cache.named = make(map[*types.Named]struct{ value, pointer *types.MethodSet })
+ }
+ // Avoid recomputing mset(*T) for each distinct Pointer
+ // instance whose underlying type is a named type.
+ msets, ok := cache.named[named]
+ if !ok {
+ msets.value = types.NewMethodSet(named)
+ msets.pointer = types.NewMethodSet(types.NewPointer(named))
+ cache.named[named] = msets
+ }
+ return msets
+}
diff --git a/vendor/golang.org/x/tools/go/types/typeutil/ui.go b/vendor/golang.org/x/tools/go/types/typeutil/ui.go
new file mode 100644
index 0000000..fa55b0a
--- /dev/null
+++ b/vendor/golang.org/x/tools/go/types/typeutil/ui.go
@@ -0,0 +1,51 @@
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package typeutil
+
+// This file defines utilities for user interfaces that display types.
+
+import "go/types"
+
+// IntuitiveMethodSet returns the intuitive method set of a type T,
+// which is the set of methods you can call on an addressable value of
+// that type.
+//
+// The result always contains MethodSet(T), and is exactly MethodSet(T)
+// for interface types and for pointer-to-concrete types.
+// For all other concrete types T, the result additionally
+// contains each method belonging to *T if there is no identically
+// named method on T itself.
+//
+// This corresponds to user intuition about method sets;
+// this function is intended only for user interfaces.
+//
+// The order of the result is as for types.MethodSet(T).
+func IntuitiveMethodSet(T types.Type, msets *MethodSetCache) []*types.Selection {
+ isPointerToConcrete := func(T types.Type) bool {
+ ptr, ok := T.(*types.Pointer)
+ return ok && !types.IsInterface(ptr.Elem())
+ }
+
+ var result []*types.Selection
+ mset := msets.MethodSet(T)
+ if types.IsInterface(T) || isPointerToConcrete(T) {
+ for i, n := 0, mset.Len(); i < n; i++ {
+ result = append(result, mset.At(i))
+ }
+ } else {
+ // T is some other concrete type.
+ // Report methods of T and *T, preferring those of T.
+ pmset := msets.MethodSet(types.NewPointer(T))
+ for i, n := 0, pmset.Len(); i < n; i++ {
+ meth := pmset.At(i)
+ if m := mset.Lookup(meth.Obj().Pkg(), meth.Obj().Name()); m != nil {
+ meth = m
+ }
+ result = append(result, meth)
+ }
+
+ }
+ return result
+}
diff --git a/vendor/modules.txt b/vendor/modules.txt
index 9fb105d..5e5a49e 100644
--- a/vendor/modules.txt
+++ b/vendor/modules.txt
@@ -1,3 +1,10 @@
+# golang.org/x/exp v0.0.0-20230711023510-fffb14384f22
+## explicit; go 1.20
+golang.org/x/exp/constraints
+golang.org/x/exp/slices
+golang.org/x/exp/slog
+golang.org/x/exp/slog/internal
+golang.org/x/exp/slog/internal/buffer
# golang.org/x/mod v0.12.0
## explicit; go 1.17
golang.org/x/mod/internal/lazyregexp
@@ -16,11 +23,13 @@ golang.org/x/tools/go/analysis/internal/checker
golang.org/x/tools/go/analysis/multichecker
golang.org/x/tools/go/analysis/passes/inspect
golang.org/x/tools/go/analysis/unitchecker
+golang.org/x/tools/go/ast/astutil
golang.org/x/tools/go/ast/inspector
golang.org/x/tools/go/gcexportdata
golang.org/x/tools/go/internal/packagesdriver
golang.org/x/tools/go/packages
golang.org/x/tools/go/types/objectpath
+golang.org/x/tools/go/types/typeutil
golang.org/x/tools/internal/diff
golang.org/x/tools/internal/diff/lcs
golang.org/x/tools/internal/event