Show metadata-only groups in parent help inventories

execute_external_test.go

@@ -505,3 +505,50 @@ func TestNilDiagnosticWritersHaveNoOutputAndDoNotHideCauses(t *testing.T) {
 		}
 	}
 }
+
+func TestParentHelpDiscoversMetadataOnlyGroups(t *testing.T) {
+	leaf, err := commandkit.Group("notes", "Read notes metadata.")
+	if err != nil {
+		t.Fatal(err)
+	}
+	parent, err := commandkit.Group("topics", "Browse topic metadata.", leaf)
+	if err != nil {
+		t.Fatal(err)
+	}
+	app, err := commandkit.New(commandkit.Identity{Name: "example"}, parent)
+	if err != nil {
+		t.Fatal(err)
+	}
+	loads := 0
+	if err := commandkit.RegisterConfig(app, commandkit.ConfigSuite[struct{}]{Scopes: []commandkit.ConfigScope[struct{}]{{Name: "app", Operations: []commandkit.ConfigOperation{commandkit.ConfigValidate}, Acquire: func(context.Context, commandkit.ConfigRequest, struct{}) (commandkit.Acquired[commandkit.ConfigView], error) {
+		loads++
+		return commandkit.Acquired[commandkit.ConfigView]{}, nil
+	}}}}); err != nil {
+		t.Fatal(err)
+	}
+	for _, tc := range []struct {
+		args    []string
+		content string
+	}{
+		{nil, "Browse topic metadata."},
+		{[]string{"topics"}, "Read notes metadata."},
+		{[]string{"topics", "--help"}, "Read notes metadata."},
+		{[]string{"help", "topics"}, "Read notes metadata."},
+		{[]string{"topics", "notes"}, "Read notes metadata."},
+		{[]string{"help", "topics", "notes"}, "Read notes metadata."},
+	} {
+		var out bytes.Buffer
+		result := app.Execute(context.Background(), tc.args, commandkit.Streams{Out: &out})
+		if result.Kind != commandkit.OutcomeSuccess || !strings.Contains(out.String(), tc.content) || loads != 0 {
+			t.Fatalf("%v: result=%#v output=%q loads=%d", tc.args, result, out.String(), loads)
+		}
+		if len(tc.args) == 1 && (!strings.Contains(out.String(), "Available Commands:") || !strings.Contains(out.String(), "[command]")) {
+			t.Fatalf("missing child inventory/usage: %q", out.String())
+		}
+	}
+	var diagnostic bytes.Buffer
+	result := app.Execute(context.Background(), []string{"topics", "unknown"}, commandkit.Streams{Err: &diagnostic})
+	if result.Kind != commandkit.OutcomeUsage || !strings.Contains(diagnostic.String(), "[command]") {
+		t.Fatalf("result=%#v diagnostic=%q", result, diagnostic.String())
+	}
+}