localrepo: unify tag related info into a tagscache class

localrepo: make invalidate() walk _filecache

localrepo: decorate manifest() with filecache

localrepo: decorate _bookmarks/current with filecache nodebookmarks() can be cached as well, leaving for later

localrepo: decorate changelog() with filecache

localrepo: refresh filecache entries after releasing a repo.lock()

localrepo: decorate dirstate() with filecache We refresh the stat info when releasing repo.wlock(), right after writing it. Also, invalidate the dirstate by deleting its attribute. This will force a stat by the decorator that actually checks if anything changed, rather than reading it again every time. Note that prior to this, there was a single dirstate instance created for a localrepo. It was invalidated by calling dirstate.invalidated(), clearing its internal attributes. As a consequence, the following construct is no longer safe: ds = repo.dirstate # keep a reference to the repo's dirstate wlock = repo.wlock() try: ds.setparents(...) finally: wlock.release() # dirstate should be written here Since it's possible that the dirstate was modified between lines #1 and #2, therefore changes to the old dirstate won't get written when the lock releases, because a new instance was created by the decorator.

localrepo: add a cache with stat info for files under .hg/