[PATCH] style: ban [ foo == bar] bashism in tests

[Jun Wu]

Seems a good exercise for greg and smf.

Excerpts from Augie Fackler's message of 2017-05-15 14:09:14 -0400:
> # HG changeset patch
> # User Augie Fackler <augie at google.com>
> # Date 1494871682 14400
> #      Mon May 15 14:08:02 2017 -0400
> # Node ID cce0fa53cc1401b5bb234acc3e846f0595febe4b
> # Parent  366db10cb40f7fb1b804bfc87c8767d79a876489
> style: ban [ foo == bar] bashism in tests
> 
> diff --git a/contrib/check-code.py b/contrib/check-code.py
> --- a/contrib/check-code.py
> +++ b/contrib/check-code.py
> @@ -116,6 +116,7 @@ testpats = [
>      (r'printf.*[^\\]\\x', "don't use printf \\x, use Python"),
>      (r'\$\(.*\)', "don't use $(expr), use `expr`"),
>      (r'rm -rf \*', "don't use naked rm -rf, target a directory"),
> +    (r'\[[^\]]+==', '[ foo == bar ] is a bashism, use [ foo = bar ] instead'),
>      (r'(^|\|\s*)grep (-\w\s+)*[^|]*[(|]\w',
>       "use egrep for extended grep syntax"),
>      (r'/bin/', "don't use explicit paths for tools"),
> diff --git a/tests/test-contrib-check-code.t b/tests/test-contrib-check-code.t
> --- a/tests/test-contrib-check-code.t
> +++ b/tests/test-contrib-check-code.t
> @@ -152,6 +152,15 @@
>     >   $ function onwarn {}
>     warning: don't use 'function', use old style
>    [1]
> +  $ cat > error.t <<EOF
> +  >   $ [ foo == bar ]
> +  > EOF
> +  $ "$check_code" error.t
> +  error.t:1:
> +   >   $ [ foo == bar ]
> +   [ foo == bar ] is a bashism, use [ foo = bar ] instead
> +  [1]
> +  $ rm error.t
>    $ cat > raise-format.py <<EOF
>    > raise SomeException, message
>    > # this next line is okay