Prototype of bzlmod-powered transitive dependencies

Modules can use the `go_deps` module extension to define Go dependencies.

Only Go module dependencies are supported for now (`go_deps.module`).

HTTP and VCS Go repositories can be implemented for the root module only
using the new bazel_module.is_root field added in
bazelbuild/bazel#15792 has been merged. They
should follow the semantics of archive_override/git_override.

.bazelci/presubmit.yml

@@ -1,6 +1,7 @@
 ---
-platforms:
+tasks:
   ubuntu1804:
+    platform: ubuntu1804
     build_targets:
     - "..."
     run_targets:
@@ -9,17 +10,32 @@ platforms:
     - "//:gazelle_ci"
     test_targets:
     - "..."
+  ubuntu1804_bcr_tests:
+    name: BCR test module
+    platform: ubuntu1804
+    # Includes https://github.com/bazelbuild/bazel/commit/4e439689db73a12b9c8a1f9f1a5f8023e09d40b0,
+    # which will eventually be released in Bazel 5.3.0.
+    bazel_version: 4e439689db73a12b9c8a1f9f1a5f8023e09d40b0
+    working_directory: tests/bcr
+    build_targets:
+      - "//..."
+      - "//:gazelle"
+    test_targets:
+      - "//..."
   ubuntu1604:
+    platform: ubuntu1604
     build_targets:
     - "..."
     test_targets:
     - "..."
   macos:
+    platform: macos
     build_targets:
     - "..."
     test_targets:
     - "..."
   windows:
+    platform: windows
     build_targets:
     - "--"
     - "..."

.bazelignore

@@ -0,0 +1 @@
+tests/bcr

.gitignore

@@ -1,5 +1,8 @@
-bazel-bazel-gazelle
-bazel-bin
-bazel-genfiles
-bazel-out
-bazel-testlogs
+/bazel-bazel-gazelle
+/bazel-bin
+/bazel-out
+/bazel-testlogs
+/tests/bcr/bazel-bcr
+/tests/bcr/bazel-bin
+/tests/bcr/bazel-out
+/tests/bcr/bazel-testlogs

BUILD.bazel

@@ -109,3 +109,10 @@ bzl_library(
         "@bazel_tools//tools/build_defs/repo:git.bzl",
     ],
 )
+
+bzl_library(
+    name = "extensions",
+    srcs = ["extensions.bzl"],
+    visibility = ["//visibility:public"],
+    deps = ["//internal/bzlmod:go_deps"],
+)

MODULE.bazel

@@ -0,0 +1,244 @@
+module(
+    name = "gazelle",
+    version = "0.26.0",
+)
+
+print("WARNING: The bazel_gazelle Bazel module is still highly experimental and subject to change at any time. Only use it to try out bzlmod for now.")
+
+bazel_dep(name = "bazel_skylib", version = "1.2.0")
+bazel_dep(name = "rules_go", version = "0.33.0", repo_name = "io_bazel_rules_go")
+
+go_sdk = use_extension("@io_bazel_rules_go//go:extensions.bzl", "go_sdk")
+
+# Known to exist since it is instantiated by rules_go itself.
+use_repo(go_sdk, "go_default_sdk")
+
+non_module_deps = use_extension("//internal/bzlmod:non_module_deps.bzl", "non_module_deps")
+use_repo(
+    non_module_deps,
+    "bazel_gazelle_go_repository_cache",
+    "bazel_gazelle_go_repository_config",
+    "bazel_gazelle_go_repository_tools",
+)
+
+go_deps = use_extension("@gazelle//:extensions.bzl", "go_deps")
+go_deps.module(
+    importpath = "honnef.co/go/tools",
+    sum = "h1:/hemPrYIhOhy8zYrNj+069zDB68us2sMGsfkFJO0iZs=",
+    version = "v0.0.0-20190523083050-ea95bdfd59fc",
+)
+go_deps.module(
+    importpath = "github.com/bazelbuild/buildtools",
+    sum = "h1:ox8T5nCkvLflRgKZ6uzzdvLDN3gbNZBgLBqA5Xgn7QA=",
+    version = "v0.0.0-20220323134444-a9f46b2bb3de",
+    build_naming_convention = "go_default_library",
+)
+go_deps.module(
+    importpath = "github.com/bazelbuild/rules_go",
+    sum = "h1:8/MDe6zCE7nYKXhlbamM1izUgJjw2ce7M5kd4QKF/3Y=",
+    version = "v0.31.0",
+)
+go_deps.module(
+    importpath = "github.com/bmatcuk/doublestar/v4",
+    sum = "h1:X0krlUVAVmtr2cRoTqR8aDMrDqnB36ht8wpWTiQ3jsA=",
+    version = "v4.0.2",
+)
+go_deps.module(
+    importpath = "github.com/BurntSushi/toml",
+    sum = "h1:WXkYYl6Yr3qBf1K79EBnL4mak0OimBfB0XUf9Vl28OQ=",
+    version = "v0.3.1",
+)
+go_deps.module(
+    importpath = "github.com/census-instrumentation/opencensus-proto",
+    sum = "h1:glEXhBS5PSLLv4IXzLA5yPRVX4bilULVyxxbrfOtDAk=",
+    version = "v0.2.1",
+)
+go_deps.module(
+    importpath = "github.com/chzyer/logex",
+    sum = "h1:Swpa1K6QvQznwJRcfTfQJmTE72DqScAa40E+fbHEXEE=",
+    version = "v1.1.10",
+)
+go_deps.module(
+    importpath = "github.com/chzyer/readline",
+    sum = "h1:fY5BOSpyZCqRo5OhCuC+XN+r/bBCmeuuJtjz+bCNIf8=",
+    version = "v0.0.0-20180603132655-2972be24d48e",
+)
+go_deps.module(
+    importpath = "github.com/chzyer/test",
+    sum = "h1:q763qf9huN11kDQavWsoZXJNW3xEE4JJyHa5Q25/sd8=",
+    version = "v0.0.0-20180213035817-a1ea475d72b1",
+)
+go_deps.module(
+    importpath = "github.com/client9/misspell",
+    sum = "h1:ta993UF76GwbvJcIo3Y68y/M3WxlpEHPWIGDkJYwzJI=",
+    version = "v0.3.4",
+)
+go_deps.module(
+    importpath = "github.com/davecgh/go-spew",
+    sum = "h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=",
+    version = "v1.1.1",
+)
+go_deps.module(
+    importpath = "github.com/envoyproxy/go-control-plane",
+    sum = "h1:4cmBvAEBNJaGARUEs3/suWRyfyBfhf7I60WBZq+bv2w=",
+    version = "v0.9.1-0.20191026205805-5f8ba28d4473",
+)
+go_deps.module(
+    importpath = "github.com/envoyproxy/protoc-gen-validate",
+    sum = "h1:EQciDnbrYxy13PgWoY8AqoxGiPrpgBZ1R8UNe3ddc+A=",
+    version = "v0.1.0",
+)
+go_deps.module(
+    importpath = "github.com/fsnotify/fsnotify",
+    sum = "h1:mZcQUHVQUQWoPXXtuf9yuEXKudkV2sx1E06UadKWpgI=",
+    version = "v1.5.1",
+)
+go_deps.module(
+    importpath = "github.com/golang/glog",
+    sum = "h1:VKtxabqXZkF25pY9ekfRL6a582T4P37/31XEstQ5p58=",
+    version = "v0.0.0-20160126235308-23def4e6c14b",
+)
+go_deps.module(
+    importpath = "github.com/golang/mock",
+    sum = "h1:G5FRp8JnTd7RQH5kemVNlMeyXQAztQ3mOWV95KxsXH8=",
+    version = "v1.1.1",
+)
+go_deps.module(
+    importpath = "github.com/golang/protobuf",
+    sum = "h1:JjCZWpVbqXDqFVmTfYWEVTMIYrL/NPdPSCHPJ0T/raM=",
+    version = "v1.4.3",
+)
+go_deps.module(
+    importpath = "github.com/google/go-cmp",
+    sum = "h1:81/ik6ipDQS2aGcBfIN5dHDB36BwrStyeAQquSYCV4o=",
+    version = "v0.5.7",
+)
+go_deps.module(
+    importpath = "github.com/pelletier/go-toml",
+    sum = "h1:tjENF6MfZAg8e4ZmZTeWaWiT2vXtsoO6+iuOjFhECwM=",
+    version = "v1.9.4",
+)
+go_deps.module(
+    importpath = "github.com/pmezard/go-difflib",
+    sum = "h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=",
+    version = "v1.0.0",
+)
+go_deps.module(
+    importpath = "github.com/prometheus/client_model",
+    sum = "h1:gQz4mCbXsO+nc9n1hCxHcGA3Zx3Eo+UHZoInFGUIXNM=",
+    version = "v0.0.0-20190812154241-14fe0d1b01d4",
+)
+go_deps.module(
+    importpath = "github.com/yuin/goldmark",
+    sum = "h1:OtISOGfH6sOWa1/qXqqAiOIAO6Z5J3AEAE18WAq6BiQ=",
+    version = "v1.4.0",
+)
+go_deps.module(
+    importpath = "cloud.google.com/go",
+    sum = "h1:e0WKqKTd5BnrG8aKH3J3h+QvEIQtSUcf2n5UZ5ZgLtQ=",
+    version = "v0.26.0",
+)
+go_deps.module(
+    importpath = "gopkg.in/check.v1",
+    sum = "h1:yhCVgyC4o1eVCa2tZl7eS0r+SDo693bJlVdllGtEeKM=",
+    version = "v0.0.0-20161208181325-20d25e280405",
+)
+go_deps.module(
+    importpath = "gopkg.in/yaml.v2",
+    sum = "h1:ZCJp+EgiOT7lHqUV2J862kp8Qj64Jo6az82+3Td9dZw=",
+    version = "v2.2.2",
+)
+go_deps.module(
+    importpath = "go.starlark.net",
+    sum = "h1:xwwDQW5We85NaTk2APgoN9202w/l0DVGp+GZMfsrh7s=",
+    version = "v0.0.0-20210223155950-e043a3d3c984",
+)
+go_deps.module(
+    importpath = "google.golang.org/appengine",
+    sum = "h1:/wp5JvzpHIxhs/dumFmF7BXTf3Z+dd4uXta4kVyO508=",
+    version = "v1.4.0",
+)
+go_deps.module(
+    importpath = "google.golang.org/genproto",
+    sum = "h1:+kGHl1aib/qcwaRi1CbqBZ1rk19r85MNUf8HaBghugY=",
+    version = "v0.0.0-20200526211855-cb27e3aa2013",
+)
+go_deps.module(
+    importpath = "google.golang.org/grpc",
+    sum = "h1:rRYRFMVgRv6E0D70Skyfsr28tDXIuuPZyWGMPdMcnXg=",
+    version = "v1.27.0",
+)
+go_deps.module(
+    importpath = "google.golang.org/protobuf",
+    sum = "h1:Ejskq+SyPohKW+1uil0JJMtmHCgJPJ/qWTxr8qp+R4c=",
+    version = "v1.25.0",
+)
+go_deps.module(
+    importpath = "golang.org/x/crypto",
+    sum = "h1:ObdrDkeb4kJdCP557AjRjq69pTHfNouLtWZG7j9rPN8=",
+    version = "v0.0.0-20191011191535-87dc89f01550",
+)
+go_deps.module(
+    importpath = "golang.org/x/exp",
+    sum = "h1:c2HOrn5iMezYjSlGPncknSEr/8x5LELb/ilJbXi9DEA=",
+    version = "v0.0.0-20190121172915-509febef88a4",
+)
+go_deps.module(
+    importpath = "golang.org/x/lint",
+    sum = "h1:XQyxROzUlZH+WIQwySDgnISgOivlhjIEwaQaJEJrrN0=",
+    version = "v0.0.0-20190313153728-d0100b6bd8b3",
+)
+go_deps.module(
+    importpath = "golang.org/x/mod",
+    sum = "h1:kQgndtyPBW/JIYERgdxfwMYh3AVStj88WQTlNDi2a+o=",
+    version = "v0.6.0-dev.0.20220106191415-9b9b3d81d5e3",
+)
+go_deps.module(
+    importpath = "golang.org/x/net",
+    sum = "h1:20cMwl2fHAzkJMEA+8J4JgqBQcQGzbisXo31MIeenXI=",
+    version = "v0.0.0-20210805182204-aaa1db679c0d",
+)
+go_deps.module(
+    importpath = "golang.org/x/oauth2",
+    sum = "h1:vEDujvNQGv4jgYKudGeI/+DAX4Jffq6hpD55MmoEvKs=",
+    version = "v0.0.0-20180821212333-d2e6202438be",
+)
+go_deps.module(
+    importpath = "golang.org/x/sync",
+    sum = "h1:5KslGYwFpkhGh+Q16bwMP3cOontH8FOep7tGV86Y7SQ=",
+    version = "v0.0.0-20210220032951-036812b2e83c",
+)
+go_deps.module(
+    importpath = "golang.org/x/sys",
+    sum = "h1:OH54vjqzRWmbJ62fjuhxy7AxFFgoHN0/DPc/UrL8cAs=",
+    version = "v0.0.0-20220319134239-a9b59b0215f8",
+)
+go_deps.module(
+    importpath = "golang.org/x/text",
+    sum = "h1:aRYxNxv6iGQlyVaZmk6ZgYEDa+Jg18DxebPSrd6bg1M=",
+    version = "v0.3.6",
+)
+go_deps.module(
+    importpath = "golang.org/x/tools",
+    sum = "h1:QjFRCZxdOhBJ/UNgnBZLbNV13DlbnK0quyivTnXJM20=",
+    version = "v0.1.10",
+)
+go_deps.module(
+    importpath = "golang.org/x/xerrors",
+    sum = "h1:go1bK/D/BFZV2I8cIQd1NKEZ+0owSTG1fDTci4IqFcE=",
+    version = "v0.0.0-20200804184101-5ec99f83aff1",
+)
+use_repo(
+    go_deps,
+    "com_github_bazelbuild_buildtools",
+    "com_github_bmatcuk_doublestar_v4",
+    "com_github_fsnotify_fsnotify",
+    "com_github_google_go_cmp",
+    "com_github_pelletier_go_toml",
+    "com_github_pmezard_go_difflib",
+    "org_golang_x_mod",
+    "org_golang_x_sync",
+    "org_golang_x_tools",
+    # Used internally by the go_deps module extension.
+    "_bazel_gazelle_go_repository_directives",
+)

extensions.bzl

@@ -0,0 +1,3 @@
+load("//internal/bzlmod:go_deps.bzl", _go_deps = "go_deps")
+
+go_deps = _go_deps

internal/BUILD.bazel

@@ -50,6 +50,7 @@ filegroup(
         "overlay_repository.bzl",
         "repository_docs.bzl",
         "repository_rules_test_errors.patch",
+        "//internal/bzlmod:all_files",
         "//internal/gazellebinarytest:all_files",
         "//internal/generationtest:all_files",
         "//internal/language:all_files",

internal/bzlmod/BUILD.bazel

@@ -0,0 +1,40 @@
+load("@bazel_skylib//:bzl_library.bzl", "bzl_library")
+
+filegroup(
+    name = "all_files",
+    testonly = True,
+    srcs = [
+        "BUILD.bazel",
+        "go_deps.bzl",
+        "non_module_deps.bzl",
+        "semver.bzl",
+    ],
+    visibility = ["//visibility:public"],
+)
+
+bzl_library(
+    name = "go_deps",
+    srcs = ["go_deps.bzl"],
+    visibility = ["//:__subpackages__"],
+    deps = [
+        ":semver",
+        "//internal:go_repository",
+    ],
+)
+
+bzl_library(
+    name = "non_module_deps",
+    srcs = ["non_module_deps.bzl"],
+    visibility = ["//:__subpackages__"],
+    deps = [
+        "//internal:go_repository_cache",
+        "//internal:go_repository_config",
+        "//internal:go_repository_tools",
+    ],
+)
+
+bzl_library(
+    name = "semver",
+    srcs = ["semver.bzl"],
+    visibility = ["//:__subpackages__"],
+)