Re: [PATCH] test-lib-functions: fix test_subcommand_inexact

> From: Derrick Stolee <derrickstolee@github.com>
> 
> The implementation of test_subcommand_inexact() was originally
> introduced in e4d0c11c0 (repack: respect kept objects with '--write-midx
> -b', 2021-12-20) with the intention to allow finding a subcommand based
> on an initial set of arguments. The inexactness was intended as a way to
> allow flexible options beyond that initial set, as opposed to
> test_subcommand() which requires that the full list of options is
> provided in its entirety.
> 
> The implementation began by copying test_subcommand() and replaced the
> repeated argument 'printf' statement to append ".*" instead of "," to
> each argument. This has a few drawbacks:
> 
> 1. Most importantly, this repeats the use of ".*" within 'expr', so the
>    inexact match is even more flexible than expected. It allows the list
>    of arguments to exist as a subsequence (with any other items included
>    between those arguments).
> 
> 2. The line 'expr="$(expr%,}"' that previously removed a trailing comma
>    now no longer does anything, since the string ends with ".*".
> 
> Both of these issues are fixed by keeping the addition of the comma in
> the printf statement, then adding ".*" after stripping out the trailing
> comma.
> 
> All existing tests continue to pass with this change, since none of them
> were taking advantage of this unintended flexibility.