cmd/api: omit outside dependencies when listing the packages in "std"

As of CL 251159, when 'go list -deps std' is run within GOROOT/src, it
treats the vendored external dependencies as real module dependencies,
not standard-library "vendor/" packages (which still exist in that
case, but are treated as distinct packages outside the "std" module).

Fixes #41358
Updates #30241

Change-Id: Ic23eae9829d90e74a340d49ca9052e9191597410
Reviewed-on: https://go-review.googlesource.com/c/go/+/254738
Run-TryBot: Bryan C. Mills <bcmills@google.com>
Trust: Bryan C. Mills <bcmills@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Michael Matloob <matloob@golang.org>
Reviewed-by: Jay Conrod <jayconrod@google.com>

diff --git a/src/cmd/api/goapi.go b/src/cmd/api/goapi.go
index 01b17b8839209d3ab242364ae25d78e6011f53af..6a80ed269b49bdb7b7528e292e9744e771de2b96 100644 (file)
--- a/src/cmd/api/goapi.go
+++ b/src/cmd/api/goapi.go
@@ -87,7 +87,10 @@ var contexts = []*build.Context{
 func contextName(c *build.Context) string {
        s := c.GOOS + "-" + c.GOARCH
        if c.CgoEnabled {
-               return s + "-cgo"
+               s += "-cgo"
+       }
+       if c.Dir != "" {
+               s += fmt.Sprintf(" [%s]", c.Dir)
        }
        return s
 }
@@ -478,6 +481,9 @@ func (w *Walker) loadImports() {
 
                cmd := exec.Command(goCmd(), "list", "-e", "-deps", "-json", "std")
                cmd.Env = listEnv(w.context)
+               if w.context.Dir != "" {
+                       cmd.Dir = w.context.Dir
+               }
                out, err := cmd.CombinedOutput()
                if err != nil {
                        log.Fatalf("loading imports: %v\n%s", err, out)
@@ -491,6 +497,7 @@ func (w *Walker) loadImports() {
                        var pkg struct {
                                ImportPath, Dir string
                                ImportMap       map[string]string
+                               Standard        bool
                        }
                        err := dec.Decode(&pkg)
                        if err == io.EOF {
@@ -503,11 +510,13 @@ func (w *Walker) loadImports() {
                        // - Package "unsafe" contains special signatures requiring
                        //   extra care when printing them - ignore since it is not
                        //   going to change w/o a language change.
-                       // - internal and vendored packages do not contribute to our
-                       //   API surface.
+                       // - Internal and vendored packages do not contribute to our
+                       //   API surface. (If we are running within the "std" module,
+                       //   vendored dependencies appear as themselves instead of
+                       //   their "vendor/" standard-library copies.)
                        // - 'go list std' does not include commands, which cannot be
                        //   imported anyway.
-                       if ip := pkg.ImportPath; ip != "unsafe" && !strings.HasPrefix(ip, "vendor/") && !internalPkg.MatchString(ip) {
+                       if ip := pkg.ImportPath; pkg.Standard && ip != "unsafe" && !strings.HasPrefix(ip, "vendor/") && !internalPkg.MatchString(ip) {
                                stdPackages = append(stdPackages, ip)
                        }
                        importDir[pkg.ImportPath] = pkg.Dir

diff --git a/src/cmd/api/goapi_test.go b/src/cmd/api/goapi_test.go
index eaccc5ceb53dd308a2d69aab8a417e65bb30c027..24620a94afc67070c5f1eef5f2bf3e28edcd07c7 100644 (file)
--- a/src/cmd/api/goapi_test.go
+++ b/src/cmd/api/goapi_test.go
@@ -216,3 +216,16 @@ func TestIssue29837(t *testing.T) {
                }
        }
 }
+
+func TestIssue41358(t *testing.T) {
+       context := new(build.Context)
+       *context = build.Default
+       context.Dir = filepath.Join(context.GOROOT, "src")
+
+       w := NewWalker(context, context.Dir)
+       for _, pkg := range w.stdPackages {
+               if strings.HasPrefix(pkg, "vendor/") || strings.HasPrefix(pkg, "golang.org/x/") {
+                       t.Fatalf("stdPackages contains unexpected package %s", pkg)
+               }
+       }
+}

diff --git a/src/cmd/go/internal/modload/load.go b/src/cmd/go/internal/modload/load.go
index 1664d8c5be855104b59832a8cde68255f0c4ccda..2fe68e6f8802e21ddb122155bb17b36cd2ca916b 100644 (file)
--- a/src/cmd/go/internal/modload/load.go
+++ b/src/cmd/go/internal/modload/load.go
@@ -1106,8 +1106,12 @@ func (ld *loader) stdVendor(parentPath, path string) string {
                // Do the same for importers beginning with the prefix 'vendor/' even if we
                // are *inside* of the 'std' module: the 'vendor/' packages that resolve
                // globally from GOROOT/src/vendor (and are listed as part of 'go list std')
-               // are distinct from the real module dependencies, and cannot import internal
-               // packages from the real module.
+               // are distinct from the real module dependencies, and cannot import
+               // internal packages from the real module.
+               //
+               // (Note that although the 'vendor/' packages match the 'std' *package*
+               // pattern, they are not part of the std *module*, and do not affect
+               // 'go mod tidy' and similar module commands when working within std.)
                vendorPath := pathpkg.Join("vendor", path)
                if _, err := os.Stat(filepath.Join(cfg.GOROOTsrc, filepath.FromSlash(vendorPath))); err == nil {
                        return vendorPath