localrepo: make restoring from backup at rollback avoid ambiguity of file stat Rollback of previous transaction restores contents of files below by renaming from 'undo.*' file. If renaming keeps ctime, mtime and size of a file, restoring is overlooked, and old contents cached before restoring isn't invalidated as expected. - .hg/bookmarks - .hg/phaseroots To avoid ambiguity of file stat at restoring, this patch invokes vfs.rename() with checkambig=True. BTW, .hg/dirstate is also restored at rollback. But it is restored by dirstate.restorebackup(), and previous patch already made it invoke vfs.rename() with checkambig=True. This patch is a part of "Exact Cache Validation Plan": https://www.mercurial-scm.org/wiki/ExactCacheValidationPlan