feat: support toml (#4)

README.md

@@ -37,6 +37,7 @@ The rational from [Uber Style Guide][1]:
 * `encoding/json` support
 * `encoding/xml` support
 * `gopkg.in/yaml.v3` support
+* `github.com/BurntSushi/toml` support
 
 ## 📦 Install
 
@@ -46,6 +47,10 @@ go install github.com/junk1tm/musttag/cmd/musttag
 
 ## 📋 Usage
 
+```shell
+musttag ./...
+```
+
 With `go vet`:
 
 ```shell
@@ -54,7 +59,6 @@ go vet -vettool=$(which musttag) ./...
 
 ## 📅 Roadmap
 
-* Support `toml`
 * Support `mapstructure`
 * Support custom tags via config
 

go.mod

@@ -3,6 +3,7 @@ module github.com/junk1tm/musttag
 go 1.18
 
 require (
+	github.com/BurntSushi/toml v1.2.1
 	golang.org/x/tools v0.3.0
 	gopkg.in/yaml.v3 v3.0.1
 )

go.sum

@@ -1,3 +1,5 @@
+github.com/BurntSushi/toml v1.2.1 h1:9F2/+DoOYIOksmaJFPw1tGFy1eDnIJXg+UHjuD8lTak=
+github.com/BurntSushi/toml v1.2.1/go.mod h1:CxXYINrC8qIiEnFrOxCa7Jy5BFHlXnUU2pbicEuybxQ=
 golang.org/x/mod v0.7.0 h1:LapD9S96VoQRhi/GrNTqeBJFrUjs5UHCAtTlgwA5oZA=
 golang.org/x/mod v0.7.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
 golang.org/x/sync v0.1.0 h1:wsuoTGHzEhffawBOhz5CYhcrV4IdKZbEyZjBMuTp12o=

musttag.go

@@ -13,6 +13,7 @@ import (
 
 	// we need these dependencies for the tests in testdata to compile.
 	// `go mod tidy` will remove them from go.mod if we don't import them here.
+	_ "github.com/BurntSushi/toml"
 	_ "gopkg.in/yaml.v3"
 )
 
@@ -84,6 +85,7 @@ func tagAndExpr(pass *analysis.Pass, call *ast.CallExpr) (string, ast.Expr, bool
 		jsonTag = "json"
 		xmlTag  = "xml"
 		yamlTag = "yaml"
+		tomlTag = "toml"
 	)
 
 	fn := typeutil.StaticCallee(pass.TypesInfo, call)
@@ -99,6 +101,7 @@ func tagAndExpr(pass *analysis.Pass, call *ast.CallExpr) (string, ast.Expr, bool
 		return jsonTag, call.Args[0], true
 	case "encoding/json.Unmarshal":
 		return jsonTag, call.Args[1], true
+
 	case "encoding/xml.Marshal",
 		"encoding/xml.MarshalIndent",
 		"(*encoding/xml.Encoder).Encode",
@@ -108,12 +111,24 @@ func tagAndExpr(pass *analysis.Pass, call *ast.CallExpr) (string, ast.Expr, bool
 		return xmlTag, call.Args[0], true
 	case "encoding/xml.Unmarshal":
 		return xmlTag, call.Args[1], true
+
 	case "gopkg.in/yaml.v3.Marshal",
 		"(*gopkg.in/yaml.v3.Encoder).Encode",
 		"(*gopkg.in/yaml.v3.Decoder).Decode":
 		return yamlTag, call.Args[0], true
 	case "gopkg.in/yaml.v3.Unmarshal":
 		return yamlTag, call.Args[1], true
+
+	case "(*github.com/BurntSushi/toml.Encoder).Encode",
+		"(*github.com/BurntSushi/toml.Decoder).Decode":
+		return tomlTag, call.Args[0], true
+	case "github.com/BurntSushi/toml.Unmarshal",
+		"github.com/BurntSushi/toml.Decode",
+		"github.com/BurntSushi/toml.DecodeFile":
+		return tomlTag, call.Args[1], true
+	case "github.com/BurntSushi/toml.DecodeFS":
+		return tomlTag, call.Args[2], true
+
 	default:
 		return "", nil, false
 	}

musttag_test.go

@@ -3,6 +3,7 @@ package musttag
 import (
 	"go/ast"
 	"go/token"
+	"path"
 	"strings"
 	"testing"
 
@@ -44,7 +45,5 @@ func shortName(name string) string {
 	name = strings.ReplaceAll(name, "*", "")
 	name = strings.ReplaceAll(name, "(", "")
 	name = strings.ReplaceAll(name, ")", "")
-	name = strings.TrimPrefix(name, "encoding/")
-	name = strings.TrimPrefix(name, "gopkg.in/")
-	return name
+	return path.Base(name)
 }

testdata/src/examples/examples.go

@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 	"encoding/xml"
 
+	"github.com/BurntSushi/toml"
 	"gopkg.in/yaml.v3"
 )
 
@@ -35,3 +36,12 @@ func exampleYAML() {
 	yaml.Marshal(user)
 	yaml.Unmarshal(nil, &user)
 }
+
+func exampleTOML() {
+	var user struct { // want `\Qexported fields should be annotated with the "toml" tag`
+		Name  string
+		Email string `toml:"email"`
+	}
+	toml.Decode("", &user)
+	toml.Unmarshal(nil, &user)
+}

testdata/src/github.com/BurntSushi/toml/toml.go

@@ -0,0 +1,25 @@
+// Package toml provides stubs for github.com/BurntSushi/toml.
+package toml
+
+import (
+	"io"
+	"io/fs"
+)
+
+func Unmarshal(_ []byte, _ any) error { return nil }
+
+type MetaData struct{}
+
+func Decode(_ string, _ any) (MetaData, error)            { return MetaData{}, nil }
+func DecodeFS(_ fs.FS, _ string, _ any) (MetaData, error) { return MetaData{}, nil }
+func DecodeFile(_ string, _ any) (MetaData, error)        { return MetaData{}, nil }
+
+type Encoder struct{}
+
+func NewEncoder(_ io.Writer) *Encoder { return nil }
+func (*Encoder) Encode(_ any) error   { return nil }
+
+type Decoder struct{}
+
+func NewDecoder(_ io.Reader) *Decoder { return nil }
+func (*Decoder) Decode(_ any) error   { return nil }

testdata/src/gopkg.in/yaml.v3/yaml.go

@@ -8,7 +8,7 @@ func Unmarshal(_ []byte, _ any) error { return nil }
 
 type Encoder struct{}
 
-func NewEncoder(w io.Writer) *Encoder { return nil }
+func NewEncoder(_ io.Writer) *Encoder { return nil }
 func (*Encoder) Encode(_ any) error   { return nil }
 
 type Decoder struct{}

testdata/src/tests/tests.go

@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 	"encoding/xml"
 
+	"github.com/BurntSushi/toml"
 	"gopkg.in/yaml.v3"
 )
 
@@ -28,7 +29,14 @@ func namedType() {
 		`\Qyaml.v3.Marshal`
 		`\Qyaml.v3.Unmarshal`
 		`\Qyaml.v3.Encoder.Encode`
-		`\Qyaml.v3.Decoder.Decode` */
+		`\Qyaml.v3.Decoder.Decode`
+
+		`\Qtoml.Unmarshal`
+		`\Qtoml.Decode`
+		`\Qtoml.DecodeFS`
+		`\Qtoml.DecodeFile`
+		`\Qtoml.Encoder.Encode`
+		`\Qtoml.Decoder.Decode` */
 		NoTag int
 	}
 	var x X
@@ -51,6 +59,13 @@ func namedType() {
 	yaml.Unmarshal(nil, &x)
 	yaml.NewEncoder(nil).Encode(X{})
 	yaml.NewDecoder(nil).Decode(&X{})
+
+	toml.Unmarshal(nil, &x)
+	toml.Decode("", &x)
+	toml.DecodeFS(nil, "", &x)
+	toml.DecodeFile("", &x)
+	toml.NewEncoder(nil).Encode(X{})
+	toml.NewDecoder(nil).Decode(&X{})
 }
 
 func nestedNamedType() {
@@ -72,11 +87,18 @@ func nestedNamedType() {
 		`\Qyaml.v3.Marshal`
 		`\Qyaml.v3.Unmarshal`
 		`\Qyaml.v3.Encoder.Encode`
-		`\Qyaml.v3.Decoder.Decode` */
+		`\Qyaml.v3.Decoder.Decode`
+
+		`\Qtoml.Unmarshal`
+		`\Qtoml.Decode`
+		`\Qtoml.DecodeFS`
+		`\Qtoml.DecodeFile`
+		`\Qtoml.Encoder.Encode`
+		`\Qtoml.Decoder.Decode` */
 		NoTag int
 	}
 	type X struct {
-		Y Y `json:"y" xml:"Y" yaml:"y"`
+		Y Y `json:"y" xml:"y" yaml:"y" toml:"y"`
 	}
 	var x X
 
@@ -98,6 +120,13 @@ func nestedNamedType() {
 	yaml.Unmarshal(nil, &x)
 	yaml.NewEncoder(nil).Encode(X{})
 	yaml.NewDecoder(nil).Decode(&X{})
+
+	toml.Unmarshal(nil, &x)
+	toml.Decode("", &x)
+	toml.DecodeFS(nil, "", &x)
+	toml.DecodeFile("", &x)
+	toml.NewEncoder(nil).Encode(X{})
+	toml.NewDecoder(nil).Decode(&X{})
 }
 
 func anonymousType() {
@@ -111,7 +140,12 @@ func anonymousType() {
 		`\Qxml.Unmarshal`
 
 		`\Qyaml.v3.Marshal`
-		`\Qyaml.v3.Unmarshal` */
+		`\Qyaml.v3.Unmarshal`
+
+		`\Qtoml.Unmarshal`
+		`\Qtoml.Decode`
+		`\Qtoml.DecodeFS`
+		`\Qtoml.DecodeFile` */
 		NoTag int
 	}
 
@@ -133,6 +167,13 @@ func anonymousType() {
 	yaml.Unmarshal(nil, &x)
 	yaml.NewEncoder(nil).Encode(struct{ NoTag int }{})  // want `\Qyaml.v3.Encoder.Encode`
 	yaml.NewDecoder(nil).Decode(&struct{ NoTag int }{}) // want `\Qyaml.v3.Decoder.Decode`
+
+	toml.Unmarshal(nil, &x)
+	toml.Decode("", &x)
+	toml.DecodeFS(nil, "", &x)
+	toml.DecodeFile("", &x)
+	toml.NewEncoder(nil).Encode(struct{ NoTag int }{})  // want `\Qtoml.Encoder.Encode`
+	toml.NewDecoder(nil).Decode(&struct{ NoTag int }{}) // want `\Qtoml.Decoder.Decode`
 }
 
 func nestedAnonymousType() {
@@ -146,8 +187,13 @@ func nestedAnonymousType() {
 		`\Qxml.Unmarshal`
 
 		`\Qyaml.v3.Marshal`
-		`\Qyaml.v3.Unmarshal` */
-		Y *struct{ NoTag int } `json:"y"`
+		`\Qyaml.v3.Unmarshal`
+
+		`\Qtoml.Unmarshal`
+		`\Qtoml.Decode`
+		`\Qtoml.DecodeFS`
+		`\Qtoml.DecodeFile` */
+		Y *struct{ NoTag int } `json:"y" xml:"y" yaml:"y" toml:"y"`
 	}
 
 	json.Marshal(x)
@@ -168,14 +214,21 @@ func nestedAnonymousType() {
 	yaml.Unmarshal(nil, &x)
 	yaml.NewEncoder(nil).Encode(struct{ Y struct{ NoTag int } }{})  // want `\Qyaml.v3.Encoder.Encode`
 	yaml.NewDecoder(nil).Decode(&struct{ Y struct{ NoTag int } }{}) // want `\Qyaml.v3.Decoder.Decode`
+
+	toml.Unmarshal(nil, &x)
+	toml.Decode("", &x)
+	toml.DecodeFS(nil, "", &x)
+	toml.DecodeFile("", &x)
+	toml.NewEncoder(nil).Encode(struct{ Y struct{ NoTag int } }{})  // want `\Qtoml.Encoder.Encode`
+	toml.NewDecoder(nil).Decode(&struct{ Y struct{ NoTag int } }{}) // want `\Qtoml.Decoder.Decode`
 }
 
 // all good, nothing to report.
 func typeWithAllTags() {
 	var x struct {
-		Y       int      `json:"y" xml:"Y" yaml:"y"`
-		Z       int      `json:"z" xml:"Z" yaml:"z"`
-		Nested  struct{} `json:"nested" xml:"Nested" yaml:"nested"`
+		Y       int      `json:"y" xml:"y" yaml:"y" toml:"y"`
+		Z       int      `json:"z" xml:"z" yaml:"z" toml:"z"`
+		Nested  struct{} `json:"nested" xml:"nested" yaml:"nested" toml:"nested"`
 		private int
 	}
 
@@ -197,6 +250,13 @@ func typeWithAllTags() {
 	yaml.Unmarshal(nil, &x)
 	yaml.NewEncoder(nil).Encode(x)
 	yaml.NewDecoder(nil).Decode(&x)
+
+	toml.Unmarshal(nil, &x)
+	toml.Decode("", &x)
+	toml.DecodeFS(nil, "", &x)
+	toml.DecodeFile("", &x)
+	toml.NewEncoder(nil).Encode(x)
+	toml.NewDecoder(nil).Decode(&x)
 }
 
 // non-static calls should be ignored.
@@ -213,6 +273,9 @@ func nonStaticCalls() {
 
 	marshalYAML := yaml.Marshal
 	marshalYAML(x)
+
+	unmarshalTOML := toml.Unmarshal
+	unmarshalTOML(nil, &x)
 }
 
 // non-struct argument calls should be ignored.
@@ -235,4 +298,11 @@ func nonStructArgument() {
 	yaml.Unmarshal(nil, &[]int{})
 	yaml.NewEncoder(nil).Encode(map[int]int{})
 	yaml.NewDecoder(nil).Decode(&map[int]int{})
+
+	toml.Unmarshal(nil, &[]int{})
+	toml.Decode("", &[]int{})
+	toml.DecodeFS(nil, "", &[]int{})
+	toml.DecodeFile("", &[]int{})
+	toml.NewEncoder(nil).Encode(map[int]int{})
+	toml.NewDecoder(nil).Decode(&map[int]int{})
 }