Double-dash -- parsing scenario

[brunk]

Thank you very much for argc. I have adopted it as my "go-to" command parser.

Summary

I have encountered a use case related to issue #251, in which parsing the command line like GNU getopt would be helpful. I, too, want to use argc to write a wrapper around another CLI tool to which I may wish to pass additional arguments and flags.

The issue arises when there are other arguments defined in addition to # @arg remaining_args~

Environment

MacOS Darwin Kernel Version 23.5.0: arm64
argc 1.19.0

Description

My sample script double-dash-tester.sh appears as follows:

#!/usr/bin/env bash

# @describe Testing out the use of double-dash to stop parsing.
# @flag -t --test Test flag
# @arg first! Search query
# @arg second=/tmp
# @arg remaining_args~

main () {
    echo -n "    "; declare -p argc_test
    echo -n "    "; declare -p argc_first
    echo -n "    "; declare -p argc_second
    echo -n "    "; declare -p argc_remaining_args
}

argc_test=""
argc_remaining_args=()
eval "$(argc --argc-eval "$0" "$@")"

With argc 1.19.0, I get the following output using a variety of flags:

$ ./double-dash-tester.sh -- 
error: the following required arguments were not provided:
  <FIRST>

$ ./double-dash-tester.sh -- first second
    declare -- argc_test=""
    declare -- argc_first="first"
    declare -- argc_second="second"
    declare -a argc_remaining_args='()'

$ ./double-dash-tester.sh first -- second
    declare -- argc_test=""
    declare -- argc_first="first"
    declare -- argc_second="second"
    declare -a argc_remaining_args='()'

$ ./double-dash-tester.sh first second -- -t
    declare -- argc_test=""
    declare -- argc_first="first"
    declare -- argc_second="second"
    declare -a argc_remaining_args='([0]="--" [1]="-t")'

My reading of GNU Standards for Command Line Interfaces and the getopt sample code is that argument parsing should terminate upon finding a --.

I would anticipate the following results if parsing terminated on --:

$ ./double-dash-tester.sh -- first second
error: the following required arguments were not provided:
  <FIRST>

$ ./double-dash-tester.sh first -- second
    declare -- argc_test=""
    declare -- argc_first="first"
    declare -- argc_second="/tmp"
    declare -a argc_remaining_args='([0]="--" [1]="second")'

$ ./double-dash-tester.sh first second -- -t
    declare -- argc_test=""
    declare -- argc_first="first"
    declare -- argc_second="second"
    declare -a argc_remaining_args='([0]="--" [1]="-t")'

I don't assume that the GNU getopt behavior is the goal, but it would be helpful in my use case since I want to pass these arguments after the double-dash on to another command.

[sigoden]

This behavior is expected.

The -- in argc means that all remaining arguments are positional and should not be parsed as options. There is no other meaning besides this.

If you prefer using --, you don't even have to use ~.

- # @arg remaining_args~
+ # @arg remaining_args*

$ ./double-dash-tester.sh first second -- -t
    declare -- argc_test=""
    declare -- argc_first="first"
    declare -- argc_second="second"
    declare -a argc_remaining_args=([0]="-t")

If you have used ~, you don't need to pass --.

$ ./double-dash-tester.sh first second -t
    declare -- argc_test=""
    declare -- argc_first="first"
    declare -- argc_second="second"
    declare -a argc_remaining_args=([0]="-t")