( )⚙ D11507 dirstate: drop all logic around the "non-normal" sets

This is an archive of the discontinued Mercurial Phabricator instance.

dirstate: drop all logic around the "non-normal" sets
ClosedPublic

Authored by SimonSapin on Sep 28 2021, 3:54 PM.

Details

Summary

The dirstate has a lot of code to compute a set of all "non-normal" and
"from_other_parent" entries.

This is all used in one, unique, location, when setparent is called and moved
from a merge to a non merge. At that time, any "merge related" information has
to be dropped. This is mostly useful for command like graft or shelve that
move to a single-parent state -before- the commit. Otherwise the commit will
already have removed all traces of the merge information in the dirstate (e.g.
for a regular merges).

The bookkeeping for these sets is quite invasive. And it seems simpler to just
drop it and do the full computation in the single location where we actually
use it (since we have to do the computation at least once anyway).

This simplify the code a lot, and clarify why this kind of computation is
needed.

The possible drawback compared to the previous code are:

  • if the operation happens in a loop, we will end up doing it multiple time,
  • the C code to detect entry of interest have been dropped, for now. It will be re-introduced later, with a processing code directly in C for even faster operation.

Diff Detail

Repository
rHG Mercurial
Lint
Automatic diff as part of commit; lint not applicable.
Unit
Automatic diff as part of commit; unit tests not applicable.

Event Timeline

SimonSapin created this revision.Sep 28 2021, 3:54 PM

Very happy that this can be dropped, it was a lot of complexity for not much (after all the refactoring, of course). I'll accept it once the description is updated to reflect that the Rust changes have indeed been done.

marmoute edited the summary of this revision. (Show Details)Sep 29 2021, 5:04 AM
Alphare accepted this revision.Sep 30 2021, 9:45 AM
This revision is now accepted and ready to land.Sep 30 2021, 9:45 AM
This revision was automatically updated to reflect the committed changes.
rust/hg-cpython/src/dirstate/non_normal_entries.rs