git-webkit will attempt to list _all_ branches for really old commits. That is extremely inefficient, especially for a project like WebKit which has thousands of branches. We should short-circuit listing all branches by first checking if a commit is explicitly on `main`.
<rdar://problem/108328653>
Specifically, it seems to be this bit that's the biggest offender: if branch != default_branch: branch = self.prioritize_branches(self.branches_for(hash), self.branch) Which will always list all branches for a given hash just to determine that hash is, in fact, on `main`.
Pull request: https://github.com/WebKit/WebKit/pull/12984
Committed 263190@main (610c7d596fb7): <https://commits.webkit.org/263190@main> Reviewed commits have been landed. Closing PR #12984 and removing active labels.
Committed 259548.676@safari-7615-branch (39b0087a0443): <https://commits.webkit.org/259548.676@safari-7615-branch> Reviewed commits have been landed. Closing PR #556 and removing active labels.