localrepo: handle ValueError during repository opening Python 3.8 can raise ValueError on attempt of an I/O operation against an illegal path. This was causing test-remotefilelog-gc.t to fail on Python 3.8. This commit teaches repository opening to handle ValueError and re-raise an Abort on failure. An arguably better solution would be to implement this logic in the vfs layer. But that seems like a bag of worms and I don't want to go down that rabbit hole. Until users report uncaught ValueError exceptions in the wild, I think it is fine to patch this at the only occurrence our test harness is finding it. Differential Revision: https://phab.mercurial-scm.org/D7944

metadata: filter the `removed` set to only contains relevant data The `files` entry can be bogus and contains too many entries. This can badly combines with the computation of `removed` inflating the set size. The can lead to the changesets centric rename computation to process much more data than needed, slowing it down (and increasing space taken by data storage). In practice newer commits already that reduced set, this applies this "fix" to older changeset. Differential Revision: https://phab.mercurial-scm.org/D8589

files: extract code for extra filtering of the `removed` entry into copies We want to reduce the set of `removed` files that to the set of files actually removed. That `removed` set is used as of the changeset centric algorithm, having smaller sets means less processing and faster computation. In this changeset we extract the code to be a function of it own. We will make use of it in the next changesets. Differential Revision: https://phab.mercurial-scm.org/D8588