dirstate-v2: Add `hg debugupgraderepo` command support
This command changes changes the file formats used inside an existing
repository to what they would be in a new repository with the current config.
For example:
hg debugupgraderepo --config format.exp-dirstate-v2=1 --run
hg debugupgraderepo --config format.exp-dirstate-v2=0 --run
If a repository has a dirstate in v1 format, the first command would upgrade it
to dirstate-v2. Conversely, if a repository has a dirstate in v2 format, the
second command would downgrade it to v1. (Both may also run some unrelated
upgrades.)
Since `format.exp-dirstate-v2` is currently disabled by default, not specifying
it in `--config` or any configuration file would result in the second command.
Differential Revision: https://phab.mercurial-scm.org/D10769
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https://www.mercurial-scm.org/wiki/ContributingChanges
If you just want a checklist to follow, you can go straight to
https://www.mercurial-scm.org/wiki/ContributingChanges#Submission_checklist
If you can't run the entire testsuite for some reason (it can be
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any files you've modified and run `python contrib/check-commit` on any
commits you've made (for example, `python contrib/check-commit
273ce12ad8f1` will report some style violations on a very old commit).