fix(protogen): refresh embedded tool metadata

Dependency setup treated any existing tools directory as current. Binaries
rebuilt after a Common upgrade could therefore use an older extracted tools
module, silently selecting stale protobuf and StarPC generator versions even
though the current Common embed carried newer pins.

Stamp the tools directory with the exact Common package identity used for
extraction. Refresh embedded metadata when that identity changes or no stamp
exists, preserve cached binaries, and advance the stamp only after extraction
succeeds. A matching stamp remains a fast no-op, and the target module files
remain untouched.

Signed-off-by: Christian Stewart <christian@aperture.us>

Author: paralin

cmd/aptre/cmd-deps.go

@@ -236,31 +236,43 @@ func ensureAllDeps(projectDir, toolsDir string, verbose, force bool) error {
 	return nil
 }
 
-func ensureToolsDir(projectDir, toolsPath string, verbose bool) error {
-	if _, err := os.Stat(toolsPath); err == nil {
-		return nil // Already exists
-	}
+func toolsStampPath(toolsPath string) string {
+	return filepath.Join(toolsPath, ".common-tools-stamp")
+}
 
-	if verbose {
-		fmt.Println("Setting up tools directory...")
+func reconcileToolsStamp(stampPath, identity string, extract func() error) (bool, error) {
+	if data, err := os.ReadFile(stampPath); err == nil && strings.TrimSpace(string(data)) == identity {
+		return false, nil
 	}
-
-	relToolsPath, err := filepath.Rel(projectDir, toolsPath)
-	if err != nil {
-		relToolsPath = filepath.Base(toolsPath)
+	if err := extract(); err != nil {
+		return false, err
+	}
+	if err := os.WriteFile(stampPath, []byte(identity+"\n"), 0o644); err != nil {
+		return false, err
 	}
+	return true, nil
+}
 
-	commonPackage := resolveCommonPackage(projectDir)
-	// Extracting the tools directory builds common's main package, which imports
-	// C++ embed packages (abseil-cpp, protobuf) that the caller's module may lack
-	// go.sum entries for. Pass -mod=mod so setup resolves them under a readonly
-	// ambient default (CI, direct binary) instead of relying on the go:aptre
-	// wrapper to set GOFLAGS.
-	cmd := exec.Command("go", "run", "-mod=mod", "-v", commonPackage, relToolsPath)
-	cmd.Dir = projectDir
-	cmd.Stdout = os.Stdout
-	cmd.Stderr = os.Stderr
-	return cmd.Run()
+func ensureToolsDir(projectDir, toolsPath string, verbose bool) error {
+	if err := os.MkdirAll(toolsPath, 0o755); err != nil {
+		return err
+	}
+	identity := resolveCommonPackage(projectDir)
+	_, err := reconcileToolsStamp(toolsStampPath(toolsPath), identity, func() error {
+		if verbose {
+			fmt.Println("Synchronizing embedded tool metadata...")
+		}
+		relToolsPath, err := filepath.Rel(projectDir, toolsPath)
+		if err != nil {
+			relToolsPath = filepath.Base(toolsPath)
+		}
+		cmd := exec.Command("go", "run", "-mod=mod", "-v", identity, relToolsPath)
+		cmd.Dir = projectDir
+		cmd.Stdout = os.Stdout
+		cmd.Stderr = os.Stderr
+		return cmd.Run()
+	})
+	return err
 }
 
 func resolveCommonPackage(projectDir string) string {

cmd/aptre/cmd-deps_test.go

@@ -7,6 +7,7 @@ import (
 	"testing"
 
 	"github.com/aperturerobotics/common/protogen"
+	"github.com/pkg/errors"
 )
 
 func TestPlanGenerateDependenciesByLanguageAndRPC(t *testing.T) {
@@ -77,3 +78,38 @@ func TestSelectedToolPlanBranches(t *testing.T) {
 		t.Fatalf("unselected product mode=%q", got.mode)
 	}
 }
+
+func TestReconcileToolsStampLifecycle(t *testing.T) {
+	path := filepath.Join(t.TempDir(), ".common-tools-stamp")
+	calls := 0
+	extract := func() error { calls++; return nil }
+	changed, err := reconcileToolsStamp(path, "common@v1", extract)
+	if err != nil || !changed || calls != 1 {
+		t.Fatalf("first %v %v %d", changed, err, calls)
+	}
+	changed, err = reconcileToolsStamp(path, "common@v1", extract)
+	if err != nil || changed || calls != 1 {
+		t.Fatalf("noop %v %v %d", changed, err, calls)
+	}
+	changed, err = reconcileToolsStamp(path, "common@v2", extract)
+	if err != nil || !changed || calls != 2 {
+		t.Fatalf("change %v %v %d", changed, err, calls)
+	}
+	os.Remove(path)
+	changed, err = reconcileToolsStamp(path, "common@v3", extract)
+	if err != nil || !changed || calls != 3 {
+		t.Fatalf("missing %v %v %d", changed, err, calls)
+	}
+}
+func TestReconcileToolsStampFailedExtractionDoesNotAdvance(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "stamp")
+	os.WriteFile(path, []byte("common@old\n"), 0o644)
+	_, err := reconcileToolsStamp(path, "common@new", func() error { return errors.New("failed") })
+	if err == nil {
+		t.Fatal("expected error")
+	}
+	got, _ := os.ReadFile(path)
+	if string(got) != "common@old\n" {
+		t.Fatalf("stamp advanced: %q", got)
+	}
+}