dagop: don't import nullrev from .node twice See 59fa3890d40a. Differential Revision: https://phab.mercurial-scm.org/D12120

stream-clone: allow to change persistent-nodemap format during stream clone Persistent nodemap affect the store format. However it is fairly isolated and fast to generate locally. So not making it a fixed part of the stream clone is useful. This allow clients without persistent-nodemap support (default for client without Rust enabled, or simply older client). So it make it possible to enable persistent nodemap on client, where it can provide a massive boost. without too much consequence. To do so, we stop using it in the advertisement requirements for streaming and let the client add/remove the necessary file depending of its configuration. We still send the files as it seems like a small save to not regenerate them. In addition, the way we match them will overlap with the changelog-v2/revlog-v2 so we can't simply skip the associated patterns. Differential Revision: https://phab.mercurial-scm.org/D12096

stream-clone: add 5000 changesets to test-clone-stream-format This make sure the changelog is not inlined. We needs this to test coming behavior change around persistent-nodemap. Differential Revision: https://phab.mercurial-scm.org/D12095

debugbuilddag: add a flag to allow running it from a non-empty repository Allow that by default seems "dangerous", but having a flag to make it possible will be useful to help building some repository incrementally. The newly introduced support is basic, but already useful. Differential Revision: https://phab.mercurial-scm.org/D12094