Method getCompletions

completions.go:316–582

(args []string)

}

func (c *Command) getCompletions(args []string) (*Command, []Completion, ShellCompDirective, error) {
	// The last argument, which is not completely typed by the user,
	// should not be part of the list of arguments
	toComplete := args[len(args)-1]
	trimmedArgs := args[:len(args)-1]

	var finalCmd *Command
	var finalArgs []string
	var err error
	// Find the real command for which completion must be performed
	// check if we need to traverse here to parse local flags on parent commands
	if c.Root().TraverseChildren {
		finalCmd, finalArgs, err = c.Root().Traverse(trimmedArgs)
	} else {
		// For Root commands that don't specify any value for their Args fields, when we call
		// Find(), if those Root commands don't have any sub-commands, they will accept arguments.
		// However, because we have added the __complete sub-command in the current code path, the
		// call to Find() -> legacyArgs() will return an error if there are any arguments.
		// To avoid this, we first remove the __complete command to get back to having no sub-commands.
		rootCmd := c.Root()
		if len(rootCmd.Commands()) == 1 {
			rootCmd.RemoveCommand(c)
		}

		finalCmd, finalArgs, err = rootCmd.Find(trimmedArgs)
	}
	if err != nil {
		// Unable to find the real command. E.g., <program> someInvalidCmd <TAB>
		return c, []Completion{}, ShellCompDirectiveDefault, fmt.Errorf("unable to find a command for arguments: %v", trimmedArgs)
	}
	finalCmd.ctx = c.ctx

	// These flags are normally added when `execute()` is called on `finalCmd`,
	// however, when doing completion, we don't call `finalCmd.execute()`.
	// Let's add the --help and --version flag ourselves but only if the finalCmd
	// has not disabled flag parsing; if flag parsing is disabled, it is up to the
	// finalCmd itself to handle the completion of *all* flags.
	if !finalCmd.DisableFlagParsing {
		finalCmd.InitDefaultHelpFlag()
		finalCmd.InitDefaultVersionFlag()
	}

	// Check if we are doing flag value completion before parsing the flags.
	// This is important because if we are completing a flag value, we need to also
	// remove the flag name argument from the list of finalArgs or else the parsing
	// could fail due to an invalid value (incomplete) for the flag.
	flag, finalArgs, toComplete, flagErr := checkIfFlagCompletion(finalCmd, finalArgs, toComplete)

	// Check if interspersed is false or -- was set on a previous arg.
	// This works by counting the arguments. Normally -- is not counted as arg but
	// if -- was already set or interspersed is false and there is already one arg then
	// the extra added -- is counted as arg.
	flagCompletion := true
	_ = finalCmd.ParseFlags(append(finalArgs, "--"))
	newArgCount := finalCmd.Flags().NArg()

	// Parse the flags early so we can check if required flags are set
	if err = finalCmd.ParseFlags(finalArgs); err != nil {