DisableFlagParsing must disable flag completion (#1161)

When a command has set DisableFlagParsing=true, it means Cobra should
not be handling flags for that command but should let the command
handle them itself.  In fact, Cobra normally won't have been told at all
about flags for this command.

Not knowing about the flags of the command also implies that Cobra
cannot perform flag completion as it does not have the necessary info.

This commit still tries to do flag name completion, but when
DisableFlagParsing==true, it continues on so that ValidArgsFunction will
be called; this allows the program to handle completion for its own
flags when DisableFlagParsing==true.

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

bash_completions.go

@@ -193,7 +193,13 @@ __%[1]s_handle_reply()
                     fi
                 fi
             fi
-            return 0;
+
+            if [[ -z "${flag_parsing_disabled}" ]]; then
+                # If flag parsing is enabled, we have completed the flags and can return.
+                # If flag parsing is disabled, we may not know all (or any) of the flags, so we fallthrough
+                # to possibly call handle_go_custom_completion.
+                return 0;
+            fi
             ;;
     esac
 
@@ -394,6 +400,7 @@ func writePostscript(buf io.StringWriter, name string) {
     fi
 
     local c=0
+    local flag_parsing_disabled=
     local flags=()
     local two_word_flags=()
     local local_nonpersistent_flags=()
@@ -535,6 +542,11 @@ func writeFlags(buf io.StringWriter, cmd *Command) {
     flags_completion=()
 
 `)
+
+	if cmd.DisableFlagParsing {
+		WriteStringAndCheck(buf, "    flag_parsing_disabled=1\n")
+	}
+
 	localNonPersistentFlags := cmd.LocalNonPersistentFlags()
 	cmd.NonInheritedFlags().VisitAll(func(flag *pflag.Flag) {
 		if nonCompletableFlag(flag) {

completions.go

@@ -266,6 +266,12 @@ func (c *Command) getCompletions(args []string) (*Command, []string, ShellCompDi
 		}
 	}
 
+	// We only remove the flags from the arguments if DisableFlagParsing is not set.
+	// This is important for commands which have requested to do their own flag completion.
+	if !finalCmd.DisableFlagParsing {
+		finalArgs = finalCmd.Flags().Args()
+	}
+
 	if flag != nil && flagCompletion {
 		// Check if we are completing a flag value subject to annotations
 		if validExts, present := flag.Annotations[BashCompFilenameExt]; present {
@@ -290,12 +296,16 @@ func (c *Command) getCompletions(args []string) (*Command, []string, ShellCompDi
 		}
 	}
 
+	var completions []string
+	var directive ShellCompDirective
+
+	// Note that we want to perform flagname completion even if finalCmd.DisableFlagParsing==true;
+	// doing this allows for completion of persistant flag names even for commands that disable flag parsing.
+	//
 	// When doing completion of a flag name, as soon as an argument starts with
 	// a '-' we know it is a flag.  We cannot use isFlagArg() here as it requires
 	// the flag name to be complete
 	if flag == nil && len(toComplete) > 0 && toComplete[0] == '-' && !strings.Contains(toComplete, "=") && flagCompletion {
-		var completions []string
-
 		// First check for required flags
 		completions = completeRequireFlags(finalCmd, toComplete)
 
@@ -322,86 +332,86 @@ func (c *Command) getCompletions(args []string) (*Command, []string, ShellCompDi
 			})
 		}
 
-		directive := ShellCompDirectiveNoFileComp
+		directive = ShellCompDirectiveNoFileComp
 		if len(completions) == 1 && strings.HasSuffix(completions[0], "=") {
 			// If there is a single completion, the shell usually adds a space
 			// after the completion.  We don't want that if the flag ends with an =
 			directive = ShellCompDirectiveNoSpace
 		}
-		return finalCmd, completions, directive, nil
-	}
 
-	// We only remove the flags from the arguments if DisableFlagParsing is not set.
+		if !finalCmd.DisableFlagParsing {
-	// This is important for commands which have requested to do their own flag completion.
+			// If DisableFlagParsing==false, we have completed the flags as known by Cobra;
-	if !finalCmd.DisableFlagParsing {
+			// we can return what we found.
-		finalArgs = finalCmd.Flags().Args()
+			// If DisableFlagParsing==true, Cobra may not be aware of all flags, so we
-	}
+			// let the logic continue to see if ValidArgsFunction needs to be called.
-
+			return finalCmd, completions, directive, nil
-	var completions []string
-	directive := ShellCompDirectiveDefault
-	if flag == nil {
-		foundLocalNonPersistentFlag := false
-		// If TraverseChildren is true on the root command we don't check for
-		// local flags because we can use a local flag on a parent command
-		if !finalCmd.Root().TraverseChildren {
-			// Check if there are any local, non-persistent flags on the command-line
-			localNonPersistentFlags := finalCmd.LocalNonPersistentFlags()
-			finalCmd.NonInheritedFlags().VisitAll(func(flag *pflag.Flag) {
-				if localNonPersistentFlags.Lookup(flag.Name) != nil && flag.Changed {
-					foundLocalNonPersistentFlag = true
-				}
-			})
 		}
-
+	} else {
-		// Complete subcommand names, including the help command
+		directive = ShellCompDirectiveDefault
-		if len(finalArgs) == 0 && !foundLocalNonPersistentFlag {
+		if flag == nil {
-			// We only complete sub-commands if:
+			foundLocalNonPersistentFlag := false
-			// - there are no arguments on the command-line and
+			// If TraverseChildren is true on the root command we don't check for
-			// - there are no local, non-persistent flags on the command-line or TraverseChildren is true
+			// local flags because we can use a local flag on a parent command
-			for _, subCmd := range finalCmd.Commands() {
+			if !finalCmd.Root().TraverseChildren {
-				if subCmd.IsAvailableCommand() || subCmd == finalCmd.helpCommand {
+				// Check if there are any local, non-persistent flags on the command-line
-					if strings.HasPrefix(subCmd.Name(), toComplete) {
+				localNonPersistentFlags := finalCmd.LocalNonPersistentFlags()
-						completions = append(completions, fmt.Sprintf("%s\t%s", subCmd.Name(), subCmd.Short))
+				finalCmd.NonInheritedFlags().VisitAll(func(flag *pflag.Flag) {
+					if localNonPersistentFlags.Lookup(flag.Name) != nil && flag.Changed {
+						foundLocalNonPersistentFlag = true
+					}
+				})
+			}
+
+			// Complete subcommand names, including the help command
+			if len(finalArgs) == 0 && !foundLocalNonPersistentFlag {
+				// We only complete sub-commands if:
+				// - there are no arguments on the command-line and
+				// - there are no local, non-persistent flags on the command-line or TraverseChildren is true
+				for _, subCmd := range finalCmd.Commands() {
+					if subCmd.IsAvailableCommand() || subCmd == finalCmd.helpCommand {
+						if strings.HasPrefix(subCmd.Name(), toComplete) {
+							completions = append(completions, fmt.Sprintf("%s\t%s", subCmd.Name(), subCmd.Short))
+						}
+						directive = ShellCompDirectiveNoFileComp
 					}
-					directive = ShellCompDirectiveNoFileComp
 				}
 			}
-		}
 
-		// Complete required flags even without the '-' prefix
+			// Complete required flags even without the '-' prefix
-		completions = append(completions, completeRequireFlags(finalCmd, toComplete)...)
+			completions = append(completions, completeRequireFlags(finalCmd, toComplete)...)
 
-		// Always complete ValidArgs, even if we are completing a subcommand name.
+			// Always complete ValidArgs, even if we are completing a subcommand name.
-		// This is for commands that have both subcommands and ValidArgs.
+			// This is for commands that have both subcommands and ValidArgs.
-		if len(finalCmd.ValidArgs) > 0 {
+			if len(finalCmd.ValidArgs) > 0 {
-			if len(finalArgs) == 0 {
+				if len(finalArgs) == 0 {
-				// ValidArgs are only for the first argument
+					// ValidArgs are only for the first argument
-				for _, validArg := range finalCmd.ValidArgs {
+					for _, validArg := range finalCmd.ValidArgs {
-					if strings.HasPrefix(validArg, toComplete) {
+						if strings.HasPrefix(validArg, toComplete) {
-						completions = append(completions, validArg)
+							completions = append(completions, validArg)
+						}
 					}
-				}
+					directive = ShellCompDirectiveNoFileComp
-				directive = ShellCompDirectiveNoFileComp
 
-				// If no completions were found within commands or ValidArgs,
+					// If no completions were found within commands or ValidArgs,
-				// see if there are any ArgAliases that should be completed.
+					// see if there are any ArgAliases that should be completed.
-				if len(completions) == 0 {
+					if len(completions) == 0 {
-					for _, argAlias := range finalCmd.ArgAliases {
+						for _, argAlias := range finalCmd.ArgAliases {
-						if strings.HasPrefix(argAlias, toComplete) {
+							if strings.HasPrefix(argAlias, toComplete) {
-							completions = append(completions, argAlias)
+								completions = append(completions, argAlias)
+							}
 						}
 					}
 				}
+
+				// If there are ValidArgs specified (even if they don't match), we stop completion.
+				// Only one of ValidArgs or ValidArgsFunction can be used for a single command.
+				return finalCmd, completions, directive, nil
 			}
 
-			// If there are ValidArgs specified (even if they don't match), we stop completion.
+			// Let the logic continue so as to add any ValidArgsFunction completions,
-			// Only one of ValidArgs or ValidArgsFunction can be used for a single command.
+			// even if we already found sub-commands.
-			return finalCmd, completions, directive, nil
+			// This is for commands that have subcommands but also specify a ValidArgsFunction.
 		}
-
-		// Let the logic continue so as to add any ValidArgsFunction completions,
-		// even if we already found sub-commands.
-		// This is for commands that have subcommands but also specify a ValidArgsFunction.
 	}
 
 	// Find the completion function for the flag or command

completions_test.go

@@ -2543,3 +2543,64 @@ func TestMultipleShorthandFlagCompletion(t *testing.T) {
 		t.Errorf("expected: %q, got: %q", expected, output)
 	}
 }
+
+func TestCompleteWithDisableFlagParsing(t *testing.T) {
+
+	flagValidArgs := func(cmd *Command, args []string, toComplete string) ([]string, ShellCompDirective) {
+		return []string{"--flag", "-f"}, ShellCompDirectiveNoFileComp
+	}
+
+	rootCmd := &Command{Use: "root", Args: NoArgs, Run: emptyRun}
+	childCmd := &Command{
+		Use:                "child",
+		Run:                emptyRun,
+		DisableFlagParsing: true,
+		ValidArgsFunction:  flagValidArgs,
+	}
+	rootCmd.AddCommand(childCmd)
+
+	rootCmd.PersistentFlags().StringP("persistent", "p", "", "persistent flag")
+	childCmd.Flags().StringP("nonPersistent", "n", "", "non-persistent flag")
+
+	// Test that when DisableFlagParsing==true, ValidArgsFunction is called to complete flag names,
+	// after Cobra tried to complete the flags it knows about.
+	childCmd.DisableFlagParsing = true
+	output, err := executeCommand(rootCmd, ShellCompNoDescRequestCmd, "child", "-")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	expected := strings.Join([]string{
+		"--persistent",
+		"-p",
+		"--nonPersistent",
+		"-n",
+		"--flag",
+		"-f",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+
+	// Test that when DisableFlagParsing==false, Cobra completes the flags itself and ValidArgsFunction is not called
+	childCmd.DisableFlagParsing = false
+	output, err = executeCommand(rootCmd, ShellCompNoDescRequestCmd, "child", "-")
+	if err != nil {
+		t.Errorf("Unexpected error: %v", err)
+	}
+
+	// Cobra was not told of any flags, so it returns nothing
+	expected = strings.Join([]string{
+		"--persistent",
+		"-p",
+		"--nonPersistent",
+		"-n",
+		":4",
+		"Completion ended with directive: ShellCompDirectiveNoFileComp", ""}, "\n")
+
+	if output != expected {
+		t.Errorf("expected: %q, got: %q", expected, output)
+	}
+}