view tests/test-merge9.t @ 25757:4d1382fd96ff

context: write dirstate out explicitly at the end of markcommitted To detect change of a file without redundant comparison of file content, dirstate recognizes a file as certainly clean, if: (1) it is already known as "normal", (2) dirstate entry for it has valid (= not "-1") timestamp, and (3) mode, size and timestamp of it on the filesystem are as same as ones expected in dirstate This works as expected in many cases, but doesn't in the corner case that changing a file keeps mode, size and timestamp of it on the filesystem. The timetable below shows steps in one of typical such situations: ---- ----------------------------------- ---------------- timestamp of "f" ---------------- dirstate file- time action mem file system ---- ----------------------------------- ---- ----- ----- * *** *** - 'hg transplant REV1 REV2 ...' - transplanting REV1 .... N - change "f", but keep size N (via 'patch.patch()') - 'dirstate.normal("f")' N *** (via 'repo.commit()') - transplanting REV2 - change "f", but keep size N (via 'patch.patch()') - aborted while patching N+1 - release wlock - 'dirstate.write()' N N N - 'hg status' shows "r1" as "clean" N N N ---- ----------------------------------- ---- ----- ----- The most important point is that 'dirstate.write()' is executed at N+1 or later. This causes writing dirstate timestamp N of "f" out successfully. If it is executed at N, 'parsers.pack_dirstate()' replaces timestamp N with "-1" before actual writing dirstate out. This issue can occur when 'hg transplant' satisfies conditions below: - multiple revisions to be transplanted change the same file - those revisions don't change mode and size of the file, and - the 2nd or later revision of them fails after changing the file The root cause of this issue is that files are changed without flushing in-memory dirstate changes via 'repo.commit()' (even though omitting 'dirstate.normallookup()' on files changed by 'patch.patch()' for efficiency also causes this issue). To detect changes of files correctly, this patch writes in-memory dirstate changes out explicitly after marking files as clean in 'committablectx.markcommitted()', which is invoked via 'repo.commit()'. After this change, timetable is changed as below: ---- ----------------------------------- ---------------- timestamp of "f" ---------------- dirstate file- time action mem file system ---- ----------------------------------- ---- ----- ----- * *** *** - 'hg transplant REV1 REV2 ...' - transplanting REV1 .... N - change "f", but keep size N (via 'patch.patch()') - 'dirstate.normal("f")' N *** (via 'repo.commit()') ----------------------------------- ---- ----- ----- - 'dirsttate.write()' -1 -1 ----------------------------------- ---- ----- ----- - transplanting REV2 - change "f", but keep size N (via 'patch.patch()') - aborted while patching N+1 - release wlock - 'dirstate.write()' -1 -1 N - 'hg status' shows "r1" as "clean" -1 -1 N ---- ----------------------------------- ---- ----- ----- To reproduce this issue in tests certainly, this patch emulates some timing critical actions as below: - change "f" at N 'patch.patch()' with 'fakepatchtime.py' explicitly changes mtime of patched files to "2000-01-01 00:00" (= N). - 'dirstate.write()' via 'repo.commit()' at N 'fakedirstatewritetime.py' forces 'pack_dirstate()' to use "2000-01-01 00:00" as "now", only if 'pack_dirstate()' is invoked via 'committablectx.markcommitted()'. - 'dirstate.write()' via releasing wlock at N+1 (or "not at N") 'pack_dirstate()' via releasing wlock uses actual timestamp at runtime as "now", and it should be different from the "2000-01-01 00:00" of "f". BTW, this patch doesn't test cases below, even though 'patch.patch()' is used similarly in these cases: 1. failure of 'hg import' or 'hg qpush' 2. success of 'hg import', 'hg qpush' or 'hg transplant' Case (1) above doesn't cause this kind of issue, because: - if patching is aborted by conflicts, changed files are committed changed files are marked as CLEAN, even though they are partially patched. - otherwise, dirstate are fully restored by 'dirstateguard' For example in timetable above, timestamp of "f" in .hg/dirstate is restored to -1 (or less than N), and subsequent 'hg status' can detect changes correctly. Case (2) always causes 'repo.status()' invocation via 'repo.commit()' just after changing files inside same wlock scope. ---- ----------------------------------- ---------------- timestamp of "f" ---------------- dirstate file- time action mem file system ---- ----------------------------------- ---- ----- ----- N *** *** - make file "f" clean N - execute 'hg foobar' .... - 'dirstate.normal("f")' N *** (e.g. via dirty check or previous 'repo.commit()') - change "f", but keep size N - 'repo.status()' (*1) (via 'repo.commit()') ---- ----------------------------------- ---- ----- ----- At a glance, 'repo.status()' at (*1) seems to cause similar issue (= "changed files are treated as clean"), but actually doesn't. 'dirstate._lastnormaltime' should be N at (*1) above, because 'dirstate.normal()' via dirty check is finished at N. Therefore, "f" changed at N (= 'dirstate._lastnormaltime') is forcibly treated as "unsure" at (*1), and changes are detected as expected (see 'dirstate.status()' for detail). If 'hg import' is executed with '--no-commit', 'repo.status()' isn't invoked just after changing files inside same wlock scope. But preceding 'dirstate.normal()' is invoked inside another wlock scope via 'cmdutil.bailifchanged()', and in-memory changes should be flushed at the end of that scope. Therefore, timestamp N of clean "f" should be replaced by -1, if 'dirstate.write()' is invoked at N. It means that condition of this issue isn't satisfied.
author FUJIWARA Katsunori <foozy@lares.dti.ne.jp>
date Wed, 08 Jul 2015 17:01:09 +0900
parents 9209c02f1f25
children e635bc9bb7d9
line wrap: on
line source

test that we don't interrupt the merge session if
a file-level merge failed

  $ hg init repo
  $ cd repo

  $ echo foo > foo
  $ echo a > bar
  $ hg ci -Am 'add foo'
  adding bar
  adding foo

  $ hg mv foo baz
  $ echo b >> bar
  $ echo quux > quux1
  $ hg ci -Am 'mv foo baz'
  adding quux1

  $ hg up -qC 0
  $ echo >> foo
  $ echo c >> bar
  $ echo quux > quux2
  $ hg ci -Am 'change foo'
  adding quux2
  created new head

test with the rename on the remote side
  $ HGMERGE=false hg merge
  merging bar
  merging bar failed!
  merging foo and baz to baz
  1 files updated, 1 files merged, 0 files removed, 1 files unresolved
  use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
  [1]
  $ hg resolve -l
  U bar
  R baz

test with the rename on the local side
  $ hg up -C 1
  3 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ HGMERGE=false hg merge
  merging bar
  merging bar failed!
  merging baz and foo to baz
  1 files updated, 1 files merged, 0 files removed, 1 files unresolved
  use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
  [1]

show unresolved
  $ hg resolve -l
  U bar
  R baz

unmark baz
  $ hg resolve -u baz

show
  $ hg resolve -l
  U bar
  U baz
  $ hg st
  M bar
  M baz
  M quux2
  ? bar.orig

re-resolve baz
  $ hg resolve baz
  merging baz and foo to baz

after resolve
  $ hg resolve -l
  U bar
  R baz

resolve all warning
  $ hg resolve
  abort: no files or directories specified
  (use --all to remerge all files)
  [255]

resolve all
  $ hg resolve -a
  merging bar
  warning: conflicts during merge.
  merging bar incomplete! (edit conflicts, then use 'hg resolve --mark')
  [1]

after
  $ hg resolve -l
  U bar
  R baz

  $ cd ..