fix(maven): skip pom.xml update when file does not exist

If pom.xml (or the configured maven.pom_path) is absent, releaser now
logs a notice and proceeds to tag and push without failing. This makes
the tool usable in non-Maven projects. An os.Stat error that is not
ErrNotExist (e.g. permission denied) still surfaces as an error.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

cmd/main.go

@@ -203,9 +203,15 @@ func run(o options) error {
 		return nil
 	}
 
-	// --- pom.xml (skipped with --tag-only) ---
-	if !o.tagOnly {
-		pomPath := filepath.Join(absRepo, cfg.Maven.PomPath)
+	// --- pom.xml (skipped with --tag-only or when the file does not exist) ---
+	pomPath := filepath.Join(absRepo, cfg.Maven.PomPath)
+	_, statErr := os.Stat(pomPath)
+	hasPom := !errors.Is(statErr, os.ErrNotExist)
+	if statErr != nil && hasPom {
+		return fmt.Errorf("check pom path: %w", statErr)
+	}
+
+	if !o.tagOnly && hasPom {
 		currentPomVersion, err := maven.ReadVersion(pomPath)
 		if err != nil {
 			return fmt.Errorf("read pom version: %w", err)
@@ -235,6 +241,8 @@ func run(o options) error {
 			return fmt.Errorf("commit pom.xml: %w", err)
 		}
 		fmt.Fprintf(os.Stderr, "info: committed: %s\n", commitMsg)
+	} else if !o.tagOnly && !hasPom {
+		fmt.Fprintln(os.Stderr, "info: no pom.xml found — skipping version bump commit")
 	}
 
 	// --- Git tag ---

cmd/main_test.go

@@ -211,6 +211,7 @@ func TestRunPomOverride(t *testing.T) {
 }
 
 func TestRunMissingPom(t *testing.T) {
+	// --pom points to a non-existent file: pom update is skipped, tag is still created.
 	_, dir := setupRepo(t)
 	addFile(t, dir, "x.go", "// fix")
 	repo, _ := gogit.PlainOpen(dir)
@@ -218,10 +219,38 @@ func TestRunMissingPom(t *testing.T) {
 	w.Add("x.go")
 	w.Commit("fix: patch", &gogit.CommitOptions{Author: testSig()})
 
-	// Use --pom to point to a non-existent file; keeps the working tree clean.
-	err := execCmd(t, "--branch", "release/1.2", "--repo", dir, "--pom", "nonexistent.xml")
-	if err == nil {
-		t.Fatal("expected error for missing pom.xml")
+	err := execCmd(t, "--no-push", "--branch", "release/1.2", "--repo", dir, "--pom", "nonexistent.xml")
+	if err != nil {
+		t.Fatalf("missing pom should be skipped, got error: %v", err)
+	}
+
+	// Tag must still have been created.
+	repo2, _ := gogit.PlainOpen(dir)
+	_, err = repo2.Tag("v1.2.0")
+	if err != nil {
+		t.Error("expected tag v1.2.0 to be created")
+	}
+}
+
+func TestRunNoPomAtDefaultPath(t *testing.T) {
+	// Repo with no pom.xml at the default path: runs without error, creates tag.
+	dir := t.TempDir()
+	repo, err := gogit.PlainInit(dir, false)
+	if err != nil {
+		t.Fatal(err)
+	}
+	addFile(t, dir, "main.go", "package main")
+	commitAll(t, repo, dir, "fix: initial")
+
+	err = execCmd(t, "--no-push", "--branch", "release/2.0", "--repo", dir)
+	if err != nil {
+		t.Fatalf("no pom.xml should not be an error: %v", err)
+	}
+
+	repo2, _ := gogit.PlainOpen(dir)
+	_, err = repo2.Tag("v2.0.0")
+	if err != nil {
+		t.Error("expected tag v2.0.0 to be created")
 	}
 }