Update shell completion to respect flag groups

Signed-off-by: Marc Khouzam <marc.khouzam@montreal.ca>

completions.go

@@ -319,6 +319,9 @@ func (c *Command) getCompletions(args []string) (*Command, []string, ShellCompDi
 	var completions []string
 	var directive ShellCompDirective
 
+	// Enforce flag groups before doing flag completions
+	finalCmd.enforceFlagGroupsForCompletion()
+
 	// Note that we want to perform flagname completion even if finalCmd.DisableFlagParsing==true;
 	// doing this allows for completion of persistent flag names even for commands that disable flag parsing.
 	//

completions_test.go

@@ -2691,3 +2691,171 @@ func TestFixedCompletions(t *testing.T) {
 		t.Errorf("expected: %q, got: %q", expected, output)
 	}
 }
+
+func TestCompletionForGroupedFlags(t *testing.T) {
+	rootCmd := &Command{
+		Use: "root",
+		Run: emptyRun,
+	}
+	childCmd := &Command{
+		Use: "child",
+		ValidArgsFunction: func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+			return []string{"subArg"}, ShellCompDirectiveNoFileComp
+		},
+		Run: emptyRun,
+	}
+	rootCmd.AddCommand(childCmd)
+
+	rootCmd.PersistentFlags().Int("group1-1", -1, "group1-1")
+	rootCmd.PersistentFlags().String("group1-2", "", "group1-2")
+
+	childCmd.Flags().Bool("group1-3", false, "group1-3")
+	childCmd.Flags().Bool("flag2", false, "flag2")
+
+	// Add flags to a group
+	childCmd.MarkFlagsRequiredTogether("group1-1", "group1-2", "group1-3")
+
+	// Test that flags in a group are not suggested without the - prefix
+	output, err := executeCommand(rootCmd, ShellCompNoDescRequestCmd, "child", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"subArg",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that flags in a group are suggested with the - prefix
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "child", "-")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--group1-1",
+		"--group1-2",
+		"--flag2",
+		"--group1-3",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that when a flag in a group is present, the other flags in the group are suggested
+	// even without the - prefix
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "child", "--group1-2", "value", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--group1-1",
+		"--group1-3",
+		"subArg",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that when all flags in a group are present, flags are not suggested without the - prefix
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "child",
+		"--group1-1", "8",
+		"--group1-2", "value2",
+		"--group1-3",
+		"")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"subArg",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}
+
+func TestCompletionForMutuallyExclusiveFlags(t *testing.T) {
+	rootCmd := &Command{
+		Use: "root",
+		Run: emptyRun,
+	}
+	childCmd := &Command{
+		Use: "child",
+		ValidArgsFunction: func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+			return []string{"subArg"}, ShellCompDirectiveNoFileComp
+		},
+		Run: emptyRun,
+	}
+	rootCmd.AddCommand(childCmd)
+
+	rootCmd.PersistentFlags().IntSlice("group1-1", []int{1}, "group1-1")
+	rootCmd.PersistentFlags().String("group1-2", "", "group1-2")
+
+	childCmd.Flags().Bool("group1-3", false, "group1-3")
+	childCmd.Flags().Bool("flag2", false, "flag2")
+
+	// Add flags to a group
+	childCmd.MarkFlagsMutuallyExclusive("group1-1", "group1-2", "group1-3")
+
+	// Test that flags in a mutually exclusive group are not suggested without the - prefix
+	output, err := executeCommand(rootCmd, ShellCompNoDescRequestCmd, "child", "")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"subArg",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that flags in a mutually exclusive group are suggested with the - prefix
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "child", "-")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--group1-1",
+		"--group1-2",
+		"--flag2",
+		"--group1-3",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that when a flag in a mutually exclusive group is present, the other flags in the group are
+	// not suggested even with the - prefix
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "child", "--group1-1", "8", "-")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected = strings.Join([]string{
+		"--group1-1", // Should be repeated since it is a slice
+		"--flag2",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}

flag_groups.go

@@ -144,16 +144,64 @@ func combineErrors(errs []error, sep string) error {
 	if len(errs) == 0 {
 		return nil
 	}
-	if len(errs) == 1{
+	if len(errs) == 1 {
 		return errs[0]
 	}
 
 	var msgs []string
 	for _, e := range errs {
-		msgs = append(msgs, "- " + e.Error())
+		msgs = append(msgs, "- "+e.Error())
 	}
 
 	// Sort values, so they can be tested/scripted against consistently.
 	sort.Strings(msgs)
 	return fmt.Errorf(strings.Join(msgs, sep))
 }
+
+// enforceFlagGroupsForCompletion will do the following:
+// - when a flag in a group is present, other flags in the group will be marked required
+// - when a flag in a mutually exclusive group is present, other flags in the group will be marked as hidden
+// This allows the standard completion logic to behave appropriately for flag groups
+func (c *Command) enforceFlagGroupsForCompletion() {
+	if c.DisableFlagParsing {
+		return
+	}
+
+	groupStatus := map[string]map[string]bool{}
+	mutuallyExclusiveGroupStatus := map[string]map[string]bool{}
+	c.Flags().VisitAll(func(pflag *flag.Flag) {
+		processFlagForGroupAnnotation(pflag, requiredAsGroup, groupStatus)
+		processFlagForGroupAnnotation(pflag, mutuallyExclusive, mutuallyExclusiveGroupStatus)
+	})
+
+	// If a flag that is part of a group is present, we make all the other flags
+	// of that group required so that the shell completion suggests them automatically
+	for flagList, flagnameAndStatus := range groupStatus {
+		for _, isSet := range flagnameAndStatus {
+			if isSet {
+				// One of the flags of the group is set, mark the other ones as required
+				for _, fName := range strings.Split(flagList, " ") {
+					c.MarkFlagRequired(fName)
+				}
+			}
+		}
+	}
+
+	// If a flag that is mutually exclusive to others is present, we hide the other
+	// flags of that group so the shell completion does not suggest them
+	for flagList, flagnameAndStatus := range mutuallyExclusiveGroupStatus {
+		for flagName, isSet := range flagnameAndStatus {
+			if isSet {
+				// One of the flags of the mutually exclusive group is set, mark the other ones as hidden
+				// Don't mark the flag that is already set as hidden because it may be an
+				// array or slice flag and therefore must continue being suggested
+				for _, fName := range strings.Split(flagList, " ") {
+					if fName != flagName {
+						flag := c.Flags().Lookup(fName)
+						flag.Hidden = true
+					}
+				}
+			}
+		}
+	}
+}

flag_groups_test.go

@@ -62,20 +62,20 @@ func TestValidateFlagGroups(t *testing.T) {
 			desc:               "Multiple required flag group not satisfied",
 			flagGroupsRequired: []string{"a b c", "a d"},
 			args:               []string{"--c=foo", "--d=foo"},
-			expectErr:          `- if any flags in the group [a b c] are set they must all be set; missing [a b]
+			expectErr: `- if any flags in the group [a b c] are set they must all be set; missing [a b]
 - if any flags in the group [a d] are set they must all be set; missing [a]`,
 		}, {
 			desc:                "Multiple exclusive flag group not satisfied",
 			flagGroupsExclusive: []string{"a b c", "a d"},
 			args:                []string{"testcmd", "--a=foo", "--c=foo", "--d=foo"},
-			expectErr:           `- if any flags in the group [a b c] are set none of the others can be; [a c] were all set
+			expectErr: `- if any flags in the group [a b c] are set none of the others can be; [a c] were all set
 - if any flags in the group [a d] are set none of the others can be; [a d] were all set`,
 		}, {
 			desc:                "Persistent flags utilize both features and can fail",
 			flagGroupsRequired:  []string{"a e", "e f"},
 			flagGroupsExclusive: []string{"f g"},
 			args:                []string{"testcmd", "--a=foo", "--f=foo", "--g=foo"},
-			expectErr:           `- if any flags in the group [a e] are set they must all be set; missing [e]
+			expectErr: `- if any flags in the group [a e] are set they must all be set; missing [e]
 - if any flags in the group [e f] are set they must all be set; missing [e]
 - if any flags in the group [f g] are set none of the others can be; [f g] were all set`,
 		}, {