cmd/go: fix handling of vendored imports in foo_test.go files

Fixes #11977.
Fixes #11988.

Change-Id: I9f80006946d3752ee6d644ee51f2decfeaca1ff6
Reviewed-on: https://go-review.googlesource.com/13230Reviewed-by: Andrew Gerrand <adg@golang.org>
Reviewed-by: Rob Pike <r@golang.org>

src/cmd/go/list.go

@@ -175,17 +175,9 @@ func runList(cmd *Command, args []string) {
 	}
 
 	for _, pkg := range load(args) {
-		// We apply vendoredImportPath here for test imports.
-		// It's not needed for regular imports, because it was
-		// done while loading the package.
-		for i, path := range pkg.TestImports {
-			path, _ = vendoredImportPath(pkg, path)
-			pkg.TestImports[i] = path
-		}
-		for i, path := range pkg.XTestImports {
-			path, _ = vendoredImportPath(pkg, path)
-			pkg.XTestImports[i] = path
-		}
+		// Show vendor-expanded paths in listing
+		pkg.TestImports = pkg.vendored(pkg.TestImports)
+		pkg.XTestImports = pkg.vendored(pkg.XTestImports)
 
 		do(pkg)
 	}

src/cmd/go/pkg.go

@@ -101,6 +101,33 @@ type Package struct {
 	gobinSubdir  bool                 // install target would be subdir of GOBIN
 }
 
+// vendored returns the vendor-resolved version of imports,
+// which should be p.TestImports or p.XTestImports, NOT p.Imports.
+// The imports in p.TestImports and p.XTestImports are not recursively
+// loaded during the initial load of p, so they list the imports found in
+// the source file, but most processing should be over the vendor-resolved
+// import paths. We do this resolution lazily both to avoid file system work
+// and because the eventual real load of the test imports (during 'go test')
+// can produce better error messages if it starts with the original paths.
+// The initial load of p loads all the non-test imports and rewrites
+// the vendored paths, so nothing should ever call p.vendored(p.Imports).
+func (p *Package) vendored(imports []string) []string {
+	if len(imports) > 0 && len(p.Imports) > 0 && &imports[0] == &p.Imports[0] {
+		panic("internal error: p.vendored(p.Imports) called")
+	}
+	seen := make(map[string]bool)
+	var all []string
+	for _, path := range imports {
+		path, _ = vendoredImportPath(p, path)
+		if !seen[path] {
+			seen[path] = true
+			all = append(all, path)
+		}
+	}
+	sort.Strings(all)
+	return all
+}
+
 // CoverVar holds the name of the generated coverage variables targeting the named file.
 type CoverVar struct {
 	File string // local file name

src/cmd/go/test.go

@@ -384,10 +384,10 @@ func runTest(cmd *Command, args []string) {
 			for _, path := range p.Imports {
 				deps[path] = true
 			}
-			for _, path := range p.TestImports {
+			for _, path := range p.vendored(p.TestImports) {
 				deps[path] = true
 			}
-			for _, path := range p.XTestImports {
+			for _, path := range p.vendored(p.XTestImports) {
 				deps[path] = true
 			}
 		}
@@ -611,10 +611,6 @@ func (b *builder) test(p *Package) (buildAction, runAction, printAction *action,
 	stk.push(p.ImportPath + "_test")
 	pxtestNeedsPtest := false
 	for i, path := range p.XTestImports {
-		if path == p.ImportPath {
-			pxtestNeedsPtest = true
-			continue
-		}
 		p1 := loadImport(path, p.Dir, p, &stk, p.build.XTestImportPos[path], useVendor)
 		if p1.Error != nil {
 			return nil, nil, nil, p1.Error
@@ -624,7 +620,11 @@ func (b *builder) test(p *Package) (buildAction, runAction, printAction *action,
 			err.Pos = "" // show full import stack
 			return nil, nil, nil, err
 		}
-		ximports = append(ximports, p1)
+		if p1.ImportPath == p.ImportPath {
+			pxtestNeedsPtest = true
+		} else {
+			ximports = append(ximports, p1)
+		}
 		p.XTestImports[i] = p1.ImportPath
 	}
 	stk.pop()

src/cmd/go/vendor_test.go

@@ -195,3 +195,52 @@ func TestVendorCache(t *testing.T) {
 	tg.runFail("build", "p")
 	tg.grepStderr("must be imported as x", "did not fail to build p")
 }
+
+func TestVendorTest2(t *testing.T) {
+	testenv.MustHaveExternalNetwork(t)
+
+	tg := testgo(t)
+	defer tg.cleanup()
+	tg.makeTempdir()
+	tg.setenv("GOPATH", tg.path("."))
+	tg.setenv("GO15VENDOREXPERIMENT", "1")
+	tg.run("get", "github.com/rsc/go-get-issue-11864")
+
+	// build -i should work
+	tg.run("build", "-i", "github.com/rsc/go-get-issue-11864")
+	tg.run("build", "-i", "github.com/rsc/go-get-issue-11864/t")
+
+	// test -i should work like build -i (golang.org/issue/11988)
+	tg.run("test", "-i", "github.com/rsc/go-get-issue-11864")
+	tg.run("test", "-i", "github.com/rsc/go-get-issue-11864/t")
+
+	// test should work too
+	tg.run("test", "github.com/rsc/go-get-issue-11864")
+	tg.run("test", "github.com/rsc/go-get-issue-11864/t")
+
+	// external tests should observe internal test exports (golang.org/issue/11977)
+	tg.run("test", "github.com/rsc/go-get-issue-11864/vendor/vendor.org/tx2")
+}
+
+func TestVendorList(t *testing.T) {
+	testenv.MustHaveExternalNetwork(t)
+
+	tg := testgo(t)
+	defer tg.cleanup()
+	tg.makeTempdir()
+	tg.setenv("GOPATH", tg.path("."))
+	tg.setenv("GO15VENDOREXPERIMENT", "1")
+	tg.run("get", "github.com/rsc/go-get-issue-11864")
+
+	tg.run("list", "-f", `{{join .TestImports "\n"}}`, "github.com/rsc/go-get-issue-11864/t")
+	tg.grepStdout("go-get-issue-11864/vendor/vendor.org/p", "did not find vendor-expanded p")
+
+	tg.run("list", "-f", `{{join .XTestImports "\n"}}`, "github.com/rsc/go-get-issue-11864/tx")
+	tg.grepStdout("go-get-issue-11864/vendor/vendor.org/p", "did not find vendor-expanded p")
+
+	tg.run("list", "-f", `{{join .XTestImports "\n"}}`, "github.com/rsc/go-get-issue-11864/vendor/vendor.org/tx2")
+	tg.grepStdout("go-get-issue-11864/vendor/vendor.org/tx2", "did not find vendor-expanded tx2")
+
+	tg.run("list", "-f", `{{join .XTestImports "\n"}}`, "github.com/rsc/go-get-issue-11864/vendor/vendor.org/tx3")
+	tg.grepStdout("go-get-issue-11864/vendor/vendor.org/tx3", "did not find vendor-expanded tx3")
+}