Re: [PATCH 29/29] t/test-lib: teach --chain-lint to detect broken &&-chains in subshells

> On Tue, Jun 26, 2018 at 5:01 PM Jeff King <peff@peff.net> wrote:
> > On Tue, Jun 26, 2018 at 04:46:18PM -0400, Eric Sunshine wrote:
> > > Some of these dangers can be de-thoothed during the linting phase by
> > > defining do-nothing shell functions:
> > >
> > >     cp () { :; }
> > >     mv () { :; }
> > >     ln () { :; }
> > >
> > > That, at least, makes the scariest case ("rm") much less so.
> >
> > Now that's an interesting idea. We can't catch every dangerous action
> > (notably ">" would be hard to override), but it should be pretty cheap
> > to cover some obvious ones.
> 
> Taking the idea a bit further, the 'sed' script could also throw away
> strings of "../" inside subshells, which would help defang the more
> difficult cases, like "echo x >../git.c". There are pathological
> cases, of course, which it wouldn't catch:
> 
>     P=../git.c
>     test_expect_success 'foo' '
>         (
>             cd dir &&
>             echo x >$P
>         )
>     '
> 
> but it does help mitigate the issue for the most typical cases.