Re: [BUG] git-submodule has bash-ism?

> John Keeping <john@keeping.me.uk> writes:
> 
> > On Wed, Jun 01, 2016 at 03:07:59PM -0400, Jeff King wrote:
> >> On Wed, Jun 01, 2016 at 07:31:00PM +0100, John Keeping wrote:
> >> 
> >> > > >  reset_submodule_urls () {
> >> > > > -	local root
> >> > > > -	root=$(pwd) &&
> >> > > >  	(
> >> > > > +		root=$(pwd) &&
> >> > > >  		cd super-clone/submodule &&
> >> > > >  		git config remote.origin.url "$root/submodule"
> >> > > >  	) &&
> >> > > >  	(
> >> > > > +		root=$(pwd) &&
> >> > > >  		cd super-clone/submodule/sub-submodule &&
> >> > > >  		git config remote.origin.url "$root/submodule"
> >> > [...]
> >> > I wonder if it's relevant that the "local root" line isn't &&-chained?
> >> > Is it possible that on some shells we ignore an error but everything
> >> > still works?
> >> 
> >> I don't think so. We're inside a function, so we wouldn't affect any
> >> outer &&-chaining in the function (and there isn't any in the caller
> >> anyway). I think it's a reasonable custom not to bother &&-chaining
> >> "local" lines, as they come at the top of a function and can't fail.
> >
> > Can't fail if the shell supports "local", but if we're in a shell that
> > doesn't support it, then the lack of "&&" may allow us to just carry on.
> 
> True, but if "to just carry on" were a correct behaviour, then
> wouldn't that mean that "local" was unnecessary, i.e. the variable
> did not have to get localized because stomping on the global name
> would not affect later reference to the same variable made by the
> caller?
> 
> If the clobbering of a global variable breaks the behaviour of the
> script, wouldn't we rather want to catch that fact?
> 
> So either way, I do not think "local variable names" that breaks
> &&-chain can be justified.  Either the variable must be localized
> for the script to work correctly, in which case we want local with
> &&-chaining, or it does not have to, in which case we do not want to
> have "local" that is not necessary, no?