custom comp: do not complete flags after args when interspersed is false (#1308)

If the interspersed option is set false and one arg is already set all
following arguments are counted as arg and not parsed as flags. Because
of that we should not offer flag completion. The same applies to arguments
followed after `--`.

Signed-off-by: Paul Holzinger <paul.holzinger@web.de>

completions_test.go

@@ -1749,6 +1749,228 @@ func TestValidArgsFuncChildCmdsWithDesc(t *testing.T) {
 	}
 }
 
+func TestFlagCompletionWithNotInterspersedArgs(t *testing.T) {
+	rootCmd := &Command{Use: "root", Run: emptyRun}
+	childCmd := &Command{
+		Use: "child",
+		Run: emptyRun,
+		ValidArgsFunction: func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+			return []string{"--validarg", "test"}, ShellCompDirectiveDefault
+		},
+	}
+	childCmd2 := &Command{
+		Use:       "child2",
+		Run:       emptyRun,
+		ValidArgs: []string{"arg1", "arg2"},
+	}
+	rootCmd.AddCommand(childCmd, childCmd2)
+	childCmd.Flags().Bool("bool", false, "test bool flag")
+	childCmd.Flags().String("string", "", "test string flag")
+	_ = childCmd.RegisterFlagCompletionFunc("string", func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+		return []string{"myval"}, ShellCompDirectiveDefault
+	})
+
+	// Test flag completion with no argument
+	output, err := executeCommand(rootCmd, ShellCompRequestCmd, "child", "--")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"--bool\ttest bool flag",
+		"--string\ttest string flag",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that no flags are completed after the -- arg
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child", "--", "-")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--validarg",
+		"test",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that no flags are completed after the -- arg with a flag set
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child", "--bool", "--", "-")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--validarg",
+		"test",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// set Interspersed to false which means that no flags should be completed after the first arg
+	childCmd.Flags().SetInterspersed(false)
+
+	// Test that no flags are completed after the first arg
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child", "arg", "--")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--validarg",
+		"test",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that no flags are completed after the fist arg with a flag set
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child", "--string", "t", "arg", "--")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--validarg",
+		"test",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Check that args are still completed after --
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child", "--", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--validarg",
+		"test",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Check that args are still completed even if flagname with ValidArgsFunction exists
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child", "--", "--string", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--validarg",
+		"test",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Check that args are still completed even if flagname with ValidArgsFunction exists
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child2", "--", "a")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"arg1",
+		"arg2",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Check that --validarg is not parsed as flag after --
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child", "--", "--validarg", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--validarg",
+		"test",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Check that --validarg is not parsed as flag after an arg
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child", "arg", "--validarg", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--validarg",
+		"test",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Check that --validarg is added to args for the ValidArgsFunction
+	childCmd.ValidArgsFunction = func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+		return args, ShellCompDirectiveDefault
+	}
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child", "--", "--validarg", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--validarg",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Check that --validarg is added to args for the ValidArgsFunction and toComplete is also set correctly
+	childCmd.ValidArgsFunction = func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+		return append(args, toComplete), ShellCompDirectiveDefault
+	}
+	output, err = executeCommand(rootCmd, ShellCompRequestCmd, "child", "--", "--validarg", "--toComp=ab")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--validarg",
+		"--toComp=ab",
+		":0",
+		"Completion ended with directive: ShellCompDirectiveDefault", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
 func TestFlagCompletionInGoWithDesc(t *testing.T) {
 	rootCmd := &Command{
 		Use: "root",