Set ExportFile on package info for external tests

tools/driver/packages/packages.go

@@ -16,11 +16,10 @@ import (
 	"sync"
 
 	"github.com/peterebden/go-cli-init/v5/logging"
+	"github.com/please-build/go-rules/tools/please_go/packageinfo"
 	"golang.org/x/sync/errgroup"
 	"golang.org/x/term"
 	"golang.org/x/tools/go/packages"
-
-	"github.com/please-build/go-rules/tools/please_go/packageinfo"
 )
 
 var log = logging.MustGetLogger()
@@ -421,7 +420,7 @@ func loadStdlibPackages() ([]*packages.Package, error) {
 		} else if err != nil {
 			return nil, err
 		}
-		pkgs = append(pkgs, packageinfo.FromBuildPackageForModule(pkg))
+		pkgs = append(pkgs, packageinfo.FromBuildPackageForModule(pkg, ""))
 	}
 	return pkgs, nil
 }

tools/please_go/packageinfo/moduleinfo.go

@@ -62,10 +62,7 @@ func WriteModuleInfo(importPath string, srcRoot, importconfig string, installPkg
 		} else if err != nil {
 			return fmt.Errorf("failed to import directory %s: %w", dir, err)
 		}
-		pkg := FromBuildPackageForModule(bpkg)
-
-		pkg.ExportFile = imports[pkg.PkgPath]
-		pkgs = append(pkgs, pkg)
+		pkgs = append(pkgs, FromBuildPackageForModule(bpkg, imports[bpkg.ImportPath]))
 	}
 	// If we're doing the stdlib, limit it to just things in the importconfig (i.e. no cmd/ packages)
 	pkgs = slices.DeleteFunc(pkgs, func(pkg *packages.Package) bool {
@@ -117,7 +114,7 @@ func loadImportConfig(filename string) (map[string]string, error) {
 }
 
 // FromBuildPackageForModule creates a packages Package from a build Package for a module.
-func FromBuildPackageForModule(bpkg *build.Package) *packages.Package {
+func FromBuildPackageForModule(bpkg *build.Package, exportFile string) *packages.Package {
 	goFiles := make([]string, len(bpkg.GoFiles)+len(bpkg.TestGoFiles)+len(bpkg.XTestGoFiles))
 	for i, file := range bpkg.GoFiles {
 		goFiles[i] = filepath.Join(bpkg.Dir, file)
@@ -145,5 +142,6 @@ func FromBuildPackageForModule(bpkg *build.Package) *packages.Package {
 		OtherFiles:      slices.Concat(bpkg.CFiles, bpkg.CXXFiles, bpkg.MFiles, bpkg.HFiles, bpkg.SFiles, bpkg.SwigFiles, bpkg.SwigCXXFiles, bpkg.SysoFiles),
 		EmbedPatterns:   bpkg.EmbedPatterns,
 		Imports:         imports,
+		ExportFile:      exportFile,
 	}
 }

tools/please_go/packageinfo/packageinfo.go

@@ -47,18 +47,11 @@ func WritePackageInfo(importPath string, srcRoot string, imports map[string]stri
 		} else if err != nil {
 			return fmt.Errorf("failed to import directory %s: %w", dir, err)
 		}
-		pkg := fromBuildPackage(bpkg, subrepo, module)
-
-		if subrepo != "" {
-			_, pkgPath, ok := strings.Cut(imports[pkg.PkgPath], pkg.PkgPath)
-			if !ok {
-				return fmt.Errorf("Cannot determine export file path for package %s from %s", pkg.PkgPath, imports[pkg.PkgPath])
-			}
-			// This is a really gross hack to sneak both paths through the one field.
-			pkg.ExportFile = filepath.Join(subrepo, pkgPath) + "|" + imports[pkg.PkgPath]
-		} else {
-			pkg.ExportFile = imports[pkg.PkgPath]
+		pkg, err := fromBuildPackage(bpkg, subrepo, module, imports[importPath])
+		if err != nil {
+			return fmt.Errorf("creating packages.Package: %w", err)
 		}
+
 		pkgs = append(pkgs, pkg)
 	}
 
@@ -95,7 +88,8 @@ func fromBuildPackage(
 	bpkg *build.Package,
 	subrepo string,
 	module string,
-) *packages.Package {
+	exportFile string,
+) (*packages.Package, error) {
 	goFiles := make([]string, len(bpkg.GoFiles)+len(bpkg.TestGoFiles)+len(bpkg.XTestGoFiles))
 	compiledGoFiles := make([]string, len(goFiles))
 	for i, file := range slices.Concat(bpkg.GoFiles, bpkg.TestGoFiles, bpkg.XTestGoFiles) {
@@ -115,6 +109,15 @@ func fromBuildPackage(
 		imports[imp] = &packages.Package{ID: imp, PkgPath: imp}
 	}
 
+	if subrepo != "" {
+		_, pkgPath, ok := strings.Cut(exportFile, bpkg.ImportPath)
+		if !ok {
+			return nil, fmt.Errorf("Cannot determine export file path for package %s from %s", bpkg.ImportPath, exportFile)
+		}
+		// This is a really gross hack to sneak both paths through the one field.
+		exportFile = filepath.Join(subrepo, pkgPath) + "|" + exportFile
+	}
+
 	name := bpkg.Name
 	id := bpkg.ImportPath
 	if len(bpkg.XTestGoFiles) > 0 || len(bpkg.XTestImports) > 0 {
@@ -130,9 +133,10 @@ func fromBuildPackage(
 		GoFiles:         goFiles,
 		CompiledGoFiles: compiledGoFiles,
 		OtherFiles:      slices.Concat(bpkg.CFiles, bpkg.CXXFiles, bpkg.MFiles, bpkg.HFiles, bpkg.SFiles, bpkg.SwigFiles, bpkg.SwigCXXFiles, bpkg.SysoFiles),
+		ExportFile:      exportFile,
 		EmbedPatterns:   bpkg.EmbedPatterns,
 		Imports:         imports,
-	}
+	}, nil
 }
 
 // modulePath returns the import path for a module, or the given one if the module isn't set.

tools/please_go/packageinfo/packageinfo_test.go

@@ -69,3 +69,66 @@ func Hello() {
 
 	assert.Equal(t, expected, pkgs)
 }
+
+func TestWritePackageInfo_ExternalTest(t *testing.T) {
+	tmpDir := t.TempDir()
+
+	// Create a simple package "foo" with only an external test file
+	fooDir := filepath.Join(tmpDir, "foo")
+	err := os.MkdirAll(fooDir, 0755)
+	require.NoError(t, err)
+
+	testSrc := `package foo_test
+
+import (
+	"testing"
+	"module/foo"
+)
+
+func TestHello(t *testing.T) {
+}
+`
+	err = os.WriteFile(filepath.Join(fooDir, "foo_test.go"), []byte(testSrc), 0644)
+	require.NoError(t, err)
+
+	imports := map[string]string{
+		"module/foo/foo_test_lib": "foo/foo_test_lib.a",
+	}
+
+	var buf bytes.Buffer
+	err = WritePackageInfo(
+		"module/foo/foo_test_lib",
+		fooDir,
+		imports,
+		"",
+		"",
+		true, // includeTests = true
+		&buf,
+	)
+	require.NoError(t, err)
+
+	var pkgs []*packages.Package
+	err = json.Unmarshal(buf.Bytes(), &pkgs)
+	require.NoError(t, err)
+
+	expected := []*packages.Package{
+		{
+			ID:              "module/foo/foo_test_lib_test",
+			Name:            "foo_test",
+			PkgPath:         "module/foo/foo_test_lib_test",
+			GoFiles:         []string{filepath.Join(fooDir, "foo_test.go")},
+			CompiledGoFiles: []string{filepath.Join(fooDir, "foo_test.go")},
+			ExportFile:      "foo/foo_test_lib.a",
+			Imports: map[string]*packages.Package{
+				"module/foo": {
+					ID: "module/foo",
+				},
+				"testing": {
+					ID: "testing",
+				},
+			},
+		},
+	}
+
+	assert.Equal(t, expected, pkgs)
+}