Git branch listing fails on Mac

On a Mac, using Acquia DevDesktop (and presumably MAMP or other option), the environment indicator module does not display the git branch name in the toolbar.

Digging through the issue a bit, I see the problem is in environment_indicator_execute_os_command(), which uses the proc_open() PHP function. There seems to be a difference in the behavior of PHP and proc_open() on different operating systems. On the Linux machines I've tested, the default current working directory (the one where the "git describe --all" command is executed) is the site's public root. On my Mac, the default current working directory is the PHP binary location (my Acquia Dev Desktop application directory). As a result, running "git describe --all" errors out because the Acquia Dev Desktop application directory is not a git repository. When I print out $stderr, I see the message "fatal: Not a git repository (or any of the parent directories): .git".

Apparently this difference is peculiar to proc_open(), as other methods of running system commands behave the same. See https://bugs.php.net/bug.php?id=50524.

Luckily proc_open() allows for an optional parameter to set the working directory. I suggest environment_indicator_execute_os_command() use this parameter to explicitly set the site's public root as the working directory for the command. Patch file incoming soon.