Report temporary metadata cleanup failures

internal/git/source_test.go

@@ -54,6 +54,31 @@ func TestTagOperationsAcceptFullSlashContainingRefs(t *testing.T) {
 	}
 }
 
+func TestCreateAnnotatedTagReportsTemporaryCleanupFailure(t *testing.T) {
+	fixture := newRemoteFixture(t)
+	cleanupErr := errors.New("cleanup failed")
+	var removed string
+	remove := func(path string) error {
+		removed = path
+		if err := os.Remove(path); err != nil {
+			return err
+		}
+		return cleanupErr
+	}
+	object, err := createAnnotatedTag(t.Context(), fixture.work, "v1.2.3", fixture.commit, []byte("note\n"), remove)
+	if !errors.Is(err, cleanupErr) || object == "" || removed == "" || !strings.Contains(err.Error(), removed) {
+		t.Fatalf("tag object = %q, cleanup path = %q, error = %v", object, removed, err)
+	}
+	if got := gitText(t, fixture.work, "rev-parse", "refs/tags/v1.2.3"); got != object {
+		t.Fatalf("local tag = %q, want %q", got, object)
+	}
+	_, err = createAnnotatedTag(t.Context(), fixture.work, "v1.2.3", fixture.commit, []byte("note\n"), remove)
+	var exit *exec.ExitError
+	if !errors.As(err, &exit) || !errors.Is(err, cleanupErr) {
+		t.Fatalf("tag creation and cleanup error = %v", err)
+	}
+}
+
 func TestTagReferenceValidationUsesGitRules(t *testing.T) {
 	fixture := newRemoteFixture(t)
 	for _, tag := range []string{"", "v1..2.3", "v1.2.3.lock", "v1.2.3/", "v1.2.3\\bad"} {

internal/git/tag.go

@@ -3,6 +3,7 @@ package git
 import (
 	"bytes"
 	"context"
+	"errors"
 	"fmt"
 	"os"
 	"strings"
@@ -12,6 +13,10 @@ import (
 // on the captured commit. Once its type and ID are established, the ID is
 // returned even if a later verification fails.
 func CreateAnnotatedTag(ctx context.Context, repositoryDir, tag, commit string, note []byte) (string, error) {
+	return createAnnotatedTag(ctx, repositoryDir, tag, commit, note, os.Remove)
+}
+
+func createAnnotatedTag(ctx context.Context, repositoryDir, tag, commit string, note []byte, remove func(string) error) (objectID string, resultErr error) {
 	if err := CheckTagRef(ctx, repositoryDir, tag); err != nil {
 		return "", err
 	}
@@ -23,7 +28,11 @@ func CreateAnnotatedTag(ctx context.Context, repositoryDir, tag, commit string,
 		return "", fmt.Errorf("create temporary release note: %w", err)
 	}
 	messagePath := message.Name()
-	defer os.Remove(messagePath)
+	defer func() {
+		if err := remove(messagePath); err != nil {
+			resultErr = errors.Join(resultErr, fmt.Errorf("remove temporary release note %q: %w", messagePath, err))
+		}
+	}()
 	if _, err := message.Write(note); err != nil {
 		_ = message.Close()
 		return "", fmt.Errorf("write temporary release note: %w", err)