fix(tool/cmd/migrate): read copyright year from src/ directory (#4841)

extractCopyrightYear now looks for versioned subdirectories under src/
(e.g. src/v1/index.ts) before falling back to src/index.ts so that the
copyright year comes from generated sources rather than the
hand-maintained top-level index.

Fixes #4814

---------

Signed-off-by: Julie Qiu <julie@golang.org>
Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

Author: julieqiu

tool/cmd/migrate/nodejs.go

@@ -350,9 +350,34 @@ func ensureNodejsPackage(l *config.Library) *config.NodejsPackage {
 // copyrightYearRegex matches "Copyright YYYY Google" in a file header.
 var copyrightYearRegex = regexp.MustCompile(`Copyright (\d{4}) Google`)
 
-// extractCopyrightYear reads the copyright year from src/index.ts.
+// versionDirRegex matches versioned directory names like v1, v2, v1beta1.
+var versionDirRegex = regexp.MustCompile(`^v\d[a-z0-9]*`)
+
+// extractCopyrightYear reads the copyright year from a versioned subdirectory
+// of src/ (e.g. src/v1/index.ts), falling back to src/index.ts if no versioned
+// directory exists.
 func extractCopyrightYear(pkgDir string) string {
-	data, err := os.ReadFile(filepath.Join(pkgDir, "src", "index.ts"))
+	srcDir := filepath.Join(pkgDir, "src")
+	entries, err := os.ReadDir(srcDir)
+	if err != nil {
+		return ""
+	}
+	var versionDirs []string
+	for _, e := range entries {
+		if e.IsDir() && versionDirRegex.MatchString(e.Name()) {
+			versionDirs = append(versionDirs, e.Name())
+		}
+	}
+	if len(versionDirs) > 0 {
+		sort.Strings(versionDirs)
+		data, err := os.ReadFile(filepath.Join(srcDir, versionDirs[0], "index.ts"))
+		if err == nil {
+			if m := copyrightYearRegex.FindSubmatch(data); len(m) > 1 {
+				return string(m[1])
+			}
+		}
+	}
+	data, err := os.ReadFile(filepath.Join(srcDir, "index.ts"))
 	if err != nil {
 		return ""
 	}

tool/cmd/migrate/nodejs_test.go

@@ -31,7 +31,7 @@ func TestBuildNodejsLibraries(t *testing.T) {
 		{
 			Name:          "google-cloud-secretmanager",
 			Version:       "6.1.0",
-			CopyrightYear: "2019",
+			CopyrightYear: "2020",
 			APIs: []*config.API{
 				{Path: "google/cloud/secretmanager/v1"},
 			},

tool/cmd/migrate/testdata/google-cloud-node/packages/google-cloud-secretmanager/src/v1/index.ts

@@ -0,0 +1,15 @@
+// Copyright 2020 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+export {SecretManagerServiceClient} from './secret_manager_service_client';