Re: [PATCH] test-lib: check Bash version for '-x' without using shell arrays

From: Johannes Sixt <j6t@kdbg.org>
Date: Jan 2, 2019, 00:20 UTC
Message-ID: <a82251fa-38e1-233e-50d3-3ed4850b4e11@kdbg.org>
In-Reply-To: <20190101231949.8184-1-szeder.dev@gmail.com>

Am 02.01.19 um 00:19 schrieb SZEDER Gábor:

Show 6 quoted lines

> Alas, it has been reported that NetBSD's /bin/sh does complain about
> them:
> 
>    ./test-lib.sh: 327: Syntax error: Bad substitution
> 
> where line 327 contains the first ${BASH_VERSINFO[0]} array access.

Show 21 quoted lines

> diff --git a/t/test-lib.sh b/t/test-lib.sh
> index 0f1faa24b2..f47a191e3b 100644
> --- a/t/test-lib.sh
> +++ b/t/test-lib.sh
> @@ -324,9 +324,12 @@ do
>   		# isn't executed with a suitable Bash version.
>   		if test -z "$test_untraceable" || {
>   		     test -n "$BASH_VERSION" && {
> -		       test ${BASH_VERSINFO[0]} -gt 4 || {
> -			 test ${BASH_VERSINFO[0]} -eq 4 &&
> -			 test ${BASH_VERSINFO[1]} -ge 1
> +		       bash_major=${BASH_VERSION%%.*}
> +		       bash_minor=${BASH_VERSION#*.}
> +		       bash_minor=${bash_minor%%.*}
> +		       test $bash_major -gt 4 || {
> +			 test $bash_major -eq 4 &&
> +			 test $bash_minor -ge 1
>   		       }
>   		     }
>   		   }
>

Would it perhaps be simpler to just hide the syntax behind eval? Like

  		if test -z "$test_untraceable" || {
  		     test -n "$BASH_VERSION" && eval '
		       test ${BASH_VERSINFO[0]} -gt 4 || {
			 test ${BASH_VERSINFO[0]} -eq 4 &&
			 test ${BASH_VERSINFO[1]} -ge 1
		       }
  		     '

-- Hannes