* Display pull request head branch even the branch deleted or repository deleted
* Merge getHeadRepo/loadHeadRepo and getBaseRepo/loadBaseRepo on pull and fill repo when pr.Issue.Repo is available
* retrieve sha from pull head when pull request branch deleted and fix tests
* Fix test
* Ensure MustHeadRepoName returns empty string if no head repo
Co-authored-by: zeripath <art27@cantab.net>
* Save patches to temporary files
* Remove SavePatch and generate patches on the fly
* Use ioutil.TempDir
* fixup! Use ioutil.TempDir
* fixup! fixup! Use ioutil.TempDir
* RemoveAll LocalCopyPath() in initIntergrationTest
* Default to status checking on PR creation
* Remove unnecessary set to StatusChecking
* Protect against unable to load repo
* Handle conflicts
* Restore original conflict setting
* In TestPullRequests update status to StatusChecking before running TestPatch
Lunny Xiao