effectflag: detect when branch changed
Store in effect flag when the branch changed between the predecessor and
its successors.
It can happens with "hg branch" + "hg commit --amend", "hg branch" + "hg
amend" or "histedit".
Differential Revision: https://phab.mercurial-scm.org/D538
effectflag: detect when date changed
Store in effect flag when the date changed between the predecessor and
its successors.
It can happens with "hg commit --amend -d", "hg amend -d" or "histedit".
Differential Revision: https://phab.mercurial-scm.org/D537
effectflag: detect when user changed
Store in effect flag when the user changed between the predecessor and its
successors.
It can happens with "hg commit --amend -u" or "histedit".
Differential Revision: https://phab.mercurial-scm.org/D536
effectflag: detect when description changed
Store in effect flag when the description changed between the predecessor and
its successors.
It can happens with "hg commit --amend -e", "hg amend -e" or "histedit".
Differential Revision: https://phab.mercurial-scm.org/D535
tests: add tests for effect flags
Add all the tests in this patch, it makes the patch quite big but will clarify
the following patches impact on tests.
Differential Revision: https://phab.mercurial-scm.org/D534
effectflag: store an empty effect flag for the moment
The idea behind effect flag is to store additional information in obs-markers
about what changed between a changeset and its successor(s). It's a low-level
information that comes without guarantees.
This information can be computed a posteriori, but only if we have all
changesets locally. This is not the case with distributed workflows where you
work with several people or on several computers (eg: laptop + build server).
Storing the effect-flag as a bitfield has several advantages:
- It's compact, we are using one byte per obs-marker at most for the effect-
flag.
- It's compoundable, the obsfate log approach needs to display evolve history
that could spans several obs-markers. Computing the effect-flag between a
changeset and its grand-grand-grand-successor is simple thanks to the
bitfield.
The effect-flag design has also some limitations:
- Evolving a changeset and reverting these changes just after would lead to
two obs-markers with the same effect-flag without information that the first
and third changesets are the same.
The effect-flag current design is a trade-off between compactness and
usefulness.
Storing this information helps commands to display a more complete and
understandable evolve history. For example, obslog (an Evolve command) use it
to improve its output:
x
62206adfd571 (34302) obscache: skip updating outdated obscache...
| rewritten(parent) by Matthieu Laneuville <matthieu.laneuville@octobus...
| rewritten(content) by Boris Feld <boris.feld@octobus.net>
The effect flag is stored in obs-markers metadata while we iterate on the
information we want to store. We plan to extend the existing obsmarkers
bit-field when the effect flag design will be stabilized.
It's different from the CommitCustody concept, effect-flag are not signed and
can be forged. It's also different from the operation metadata as the command
name (for example: amend) could alter a changeset in different ways (changing
the content with hg amend, changing the description with hg amend -e, changing
the user with hg amend -U). Also it's compatible with every custom command
that writes obs-markers without needing to be updated.
The effect-flag is placed behind an experimental flag set to off by default.
Hook the saving of effect flag in create markers, but store only an empty one
for the moment, I will refine the values in effect flag in following patches.
For more information, see:
https://www.mercurial-scm.org/wiki/ChangesetEvolutionDevel#Record_types_of_operation
Differential Revision: https://phab.mercurial-scm.org/D533