From: Denton Liu <liu.denton@gmail.com>
Date: Thu, 30 Apr 2020 09:22:20 GMT
Subject: Re: [PATCH 4/4] lib-submodule-update: pass OVERWRITING_FAIL
Message-ID: <20200430092220.GA25331@generichostname>
In-Reply-To: <xmqqd07ptzbw.fsf@gitster.c.googlers.com>

On Wed, Apr 29, 2020 at 08:41:23PM -0700, Junio C Hamano wrote:
> Denton Liu <liu.denton@gmail.com> writes:
> 
> >> Here, $command may or may not be a git command and more importantly,
> >> it could be a shell function, right?  Then we need to take it into
> >> account that 
> >> 
> >> 	VAR=VAL shell_function args...
> >> 
> >> will not work, no?
> >> 
> >> Some shells do not make this a single-shot environment variable
> >> assignment that will not persist once the single function invocation
> >> returns.
> >
> > ...
> > which makes me suspect that these shells are not POSIX-compliant. What
> > are some examples of shells that behave this way?
> 
> I think the most relevant thread is the one that contains this
> message:
> 
>   https://public-inbox.org/git/7vljfzz0yd.fsf@alter.siamese.dyndns.org/
> 
> FWIW, shells that do not retain the assignment after a function
> returns are not POSIX compliant.

Hmm, interesting. Running an experiment:

	$ cat test.sh
	f () {
		echo $var
	}

	var=test f
	echo $var
	$ bash test.sh
	test

	$ bash --posix test.sh
	test
	test
	$ dash test.sh
	test


So it seems like there's a bug in dash. Guess it's time to file a bug
report...