tree 707b9fbcd55124b54e179bebe004e55f71f77f4a
parent ed7b53995d52e61579e8d9fc96ed0a02f4c84dba
author ZauberNerd <zaubernerd@zaubernerd.de> 1496319710 +0200
committer Steve Gill <stevengill97@gmail.com> 1507158105 -0700

Fix null-access errors in "addTo/removeFrom*PbxGroup" methods

The project exposes a few methods to add/remove children from PbxGroups
* `addToPluginsPbxGroup` / `removeFromPluginsPbxGroup`
* `addToResourcesPbxGroup` / `removeFromResourcesPbxGroup`
* `addToFrameworksPbxGroup` / `removeFromFrameworksPbxGroup`
* `addToProductsPbxGroup` / `removeFromProductsPbxGroup`
which are used internally in:
* `addPluginFile` / `removePluginFile`
* `addResourceFile` / `removeResourceFile`
* `addProductFile` / `removeProductFile`
* `addFramework` / `removeFramework`

But neither of these methods do a check whether the `PbxGroup` actually
exists before trying to modify it - this can result in a possible
null-access error.
I ran into this problem when trying to add a framework to a project
which didn't have a `Frameworks` `PbxGroup`.

This commit adds checks to these methods to test for existence of the
`PbxGroup`s and creates them if they don't exist or does an early exit
in the case of removal.

 This closes #3