Mercurial > hg
view tests/test-basic.t @ 36672:9e7b14caf67f
xdiff: remove patience and histogram diff algorithms
Patience diff is the normal diff algorithm, plus some greediness that
unconditionally matches common common unique lines. That means it is easy to
construct cases to let it generate suboptimal result, like:
```
open('a', 'w').write('\n'.join(list('a' + 'x' * 300 + 'u' + 'x' * 700 + 'a\n')))
open('b', 'w').write('\n'.join(list('b' + 'x' * 700 + 'u' + 'x' * 300 + 'b\n')))
```
Patience diff has been advertised as being able to generate better results for
some C code changes. However, the more scientific way to do that is the
indention heuristic [1].
Since patience diff could generate suboptimal result more easily and its
"better" diff feature could be replaced by the new indention heuristic, let's
just remove it and its variant histogram diff to simplify the code.
[1]: https://github.com/git/git/commit/433860f3d0beb0c6f205290bd16cda413148f098
Test Plan:
`gcc -fPIC *.c --shared -o xdiff.so` still builds.
Differential Revision: https://phab.mercurial-scm.org/D2573
author | Jun Wu <quark@fb.com> |
---|---|
date | Sat, 03 Mar 2018 10:39:55 -0800 |
parents | 159b04de5fb0 |
children | 5890e5872f36 |
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Create a repository: $ hg config devel.all-warnings=true devel.default-date=0 0 extensions.fsmonitor= (fsmonitor !) largefiles.usercache=$TESTTMP/.cache/largefiles lfs.usercache=$TESTTMP/.cache/lfs ui.slash=True ui.interactive=False ui.mergemarkers=detailed ui.promptecho=True web.address=localhost web\.ipv6=(?:True|False) (re) $ hg init t $ cd t Prepare a changeset: $ echo a > a $ hg add a $ hg status A a Writes to stdio succeed and fail appropriately #if devfull $ hg status 2>/dev/full A a $ hg status >/dev/full abort: No space left on device [255] #endif #if devfull $ hg status >/dev/full 2>&1 [255] $ hg status ENOENT 2>/dev/full [255] #endif $ hg commit -m test This command is ancient: $ hg history changeset: 0:acb14030fe0a tag: tip user: test date: Thu Jan 01 00:00:00 1970 +0000 summary: test Verify that updating to revision 0 via commands.update() works properly $ cat <<EOF > update_to_rev0.py > from mercurial import ui, hg, commands > myui = ui.ui.load() > repo = hg.repository(myui, path=b'.') > commands.update(myui, repo, rev=0) > EOF $ hg up null 0 files updated, 0 files merged, 1 files removed, 0 files unresolved $ $PYTHON ./update_to_rev0.py 1 files updated, 0 files merged, 0 files removed, 0 files unresolved $ hg identify -n 0 Poke around at hashes: $ hg manifest --debug b789fdd96dc2f3bd229c1dd8eedf0fc60e2b68e3 644 a $ hg cat a a Verify should succeed: $ hg verify checking changesets checking manifests crosschecking files in changesets and manifests checking files 1 files, 1 changesets, 1 total revisions Repository root: $ hg root $TESTTMP/t $ hg log -l1 -T '{reporoot}\n' $TESTTMP/t At the end... $ cd ..