Kostia Balytskyi 2035a34a0e commit_rewriting: do not create accidental Preserved syncs ... Summary: Our higher-level goal is to get rid of `CommitSyncOutcome::Preserved` altogether. This diff is a step in that direction. Specifically, this diff removes the creation of "accidental" Preserved commits: the ones where the hashes are identical, although a `Mover` of some version have been applied. There are a few sides to this fix: - `get_commit_sync_outcome` now returns `Preserved` only when the source and target hashes are identical, plus stored version is `None` (previously it would only look at hashes). - `sync_commit_no_parents` now records the `Mover` version it used to rewrite the commit (previously it did not, which would sometimes create `Preserved` roots) - there are now just two ways to sync commits as `Preserved`: - `unsafe_preserve_commit` (when the caller explicitly asks for it). The idea is to only remove it once we remove the callers of this methods, of course. - `sync_commit_single_parent` when the parent is also `Preserved`. Note that automatically upgrading from `Preserved` parent to a rewritten changeset is incorrect for now: `Preserved` does not have an associated version by definition, so we would have to use a current version, which may corrupt the repo. Once we get rid of `Preserved`, this case will naturally go away. - as we now have `update_mapping_with_version` and `update_mapping` (which consumes current version), we need to add explicit `update_mapping_no_version` for preserved commits we are still creating (again, recording a current version is a mistake here, same reason as above) NB: I've added/changed a bunch of `println`s in tests, leaving them here, as they are genuinely useful IMO and not harmful. Reviewed By: StanislavGlebik Differential Revision: D24142837 fbshipit-source-id: 2153d3c5cc406b3410eadbdfca370f79d01471f9		2020-10-08 02:43:19 -07:00
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src	commit_rewriting: do not create accidental Preserved syncs	2020-10-08 02:43:19 -07:00
Cargo.toml	mononoke: remove create_commit_syncer_from_matches	2020-09-23 04:30:41 -07:00