fix: hide empty files in a config directory

CHANGELOG.md

@@ -35,3 +35,5 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   warning, and `task deps` and `task icon` no longer print spurious warnings.
 - `task deps` on Debian/Ubuntu installs the Wayland headers that current Fyne
   needs to build.
+- Empty or comment-only files in a config directory, such as Docker bind-mount
+  placeholders, no longer show up as unmanaged services.

main.go

@@ -327,6 +327,8 @@ func listServices(target string, isFile bool) ([]Service, error) {
 		doc, err := readDoc(filepath.Join(target, n))
 		if err != nil {
 			log.Print(err)
+		} else if len(doc) == 0 {
+			continue // empty or comment-only, e.g. a bind-mount placeholder; unreadable files still get a row
 		}
 		svcs := extract(doc, n)
 		if len(svcs) == 0 {

main_test.go

@@ -107,3 +107,30 @@ func TestDisabledRoundTrip(t *testing.T) {
 		t.Fatalf("re-enable: %+v", got)
 	}
 }
+
+// Empty files (bind-mount placeholders) are hidden, but a broken file must stay visible:
+// Traefik rejects the whole directory over it.
+func TestListServicesDirectory(t *testing.T) {
+	dir := t.TempDir()
+	for name, body := range map[string]string{
+		"placeholder.yaml": "# mount point only\n",
+		"empty.yml":        "",
+		"broken.yml":       "http: [\n",
+		"tls.yml":          "tls:\n  certificates: []\n",
+	} {
+		if err := os.WriteFile(filepath.Join(dir, name), []byte(body), 0o600); err != nil {
+			t.Fatal(err)
+		}
+	}
+	got, err := listServices(dir, false)
+	if err != nil {
+		t.Fatal(err)
+	}
+	var names []string
+	for _, s := range got {
+		names = append(names, s.Name)
+	}
+	if want := []string{"broken", "tls"}; !reflect.DeepEqual(names, want) {
+		t.Fatalf("listed %v, want %v", names, want)
+	}
+}