Add IsHidden flag (#6)

acmd.go

@@ -46,6 +46,9 @@ type Command struct {
 
 	// subcommands of the command.
 	Subcommands []Command
+
+	// IsHidden reports whether command should not be show in help. Default false.
+	IsHidden bool
 }
 
 // Config for the runner.
@@ -297,6 +300,9 @@ func printCommands(w io.Writer, cmds []Command) {
 	minwidth, tabwidth, padding, padchar, flags := 0, 0, 11, byte(' '), uint(0)
 	tw := tabwriter.NewWriter(w, minwidth, tabwidth, padding, padchar, flags)
 	for _, cmd := range cmds {
+		if cmd.IsHidden {
+			continue
+		}
 		desc := cmd.Description
 		if desc == "" {
 			desc = "<no description>"

acmd_test.go

@@ -264,3 +264,24 @@ func TestRunner_suggestCommand(t *testing.T) {
 		}
 	}
 }
+
+func TestCommand_IsHidden(t *testing.T) {
+	buf := &bytes.Buffer{}
+	cmds := []Command{
+		{Name: "for", Do: nopFunc},
+		{Name: "foo", Do: nopFunc, IsHidden: true},
+		{Name: "bar", Do: nopFunc},
+	}
+	r := RunnerOf(cmds, Config{
+		Args:    []string{"help"},
+		AppName: "ci",
+		Output:  buf,
+	})
+	if err := r.Run(); err != nil {
+		t.Fatal(err)
+	}
+
+	if strings.Contains(buf.String(), "foo") {
+		t.Fatal("should not show foo")
+	}
+}