view tests/test-histedit-fold-non-commute.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.

  $ . "$TESTDIR/histedit-helpers.sh"

  $ cat >> $HGRCPATH <<EOF
  > [extensions]
  > histedit=
  > EOF

  $ initrepo ()
  > {
  >     hg init $1
  >     cd $1
  >     for x in a b c d e f ; do
  >         echo $x$x$x$x$x > $x
  >         hg add $x
  >     done
  >     hg ci -m 'Initial commit'
  >     for x in a b c d e f ; do
  >         echo $x > $x
  >         hg ci -m $x
  >     done
  >     echo 'I can haz no commute' > e
  >     hg ci -m 'does not commute with e'
  >     cd ..
  > }

  $ initrepo r
  $ cd r
Initial generation of the command files

  $ EDITED="$TESTTMP/editedhistory"
  $ hg log --template 'pick {node|short} {rev} {desc}\n' -r 3 >> $EDITED
  $ hg log --template 'pick {node|short} {rev} {desc}\n' -r 4 >> $EDITED
  $ hg log --template 'fold {node|short} {rev} {desc}\n' -r 7 >> $EDITED
  $ hg log --template 'pick {node|short} {rev} {desc}\n' -r 5 >> $EDITED
  $ hg log --template 'pick {node|short} {rev} {desc}\n' -r 6 >> $EDITED
  $ cat $EDITED
  pick 65a9a84f33fd 3 c
  pick 00f1c5383965 4 d
  fold 39522b764e3d 7 does not commute with e
  pick 7b4e2f4b7bcd 5 e
  pick 500cac37a696 6 f

log before edit
  $ hg log --graph
  @  changeset:   7:39522b764e3d
  |  tag:         tip
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     does not commute with e
  |
  o  changeset:   6:500cac37a696
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     f
  |
  o  changeset:   5:7b4e2f4b7bcd
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     e
  |
  o  changeset:   4:00f1c5383965
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     d
  |
  o  changeset:   3:65a9a84f33fd
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     c
  |
  o  changeset:   2:da6535b52e45
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     b
  |
  o  changeset:   1:c1f09da44841
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     a
  |
  o  changeset:   0:1715188a53c7
     user:        test
     date:        Thu Jan 01 00:00:00 1970 +0000
     summary:     Initial commit
  

edit the history
  $ hg histedit 3 --commands $EDITED 2>&1 | fixbundle
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  merging e
  warning: conflicts during merge.
  merging e incomplete! (edit conflicts, then use 'hg resolve --mark')
  Fix up the change and run hg histedit --continue

fix up
  $ echo 'I can haz no commute' > e
  $ hg resolve --mark e
  (no more unresolved files)
  $ cat > cat.py <<EOF
  > import sys
  > print open(sys.argv[1]).read()
  > print
  > print
  > EOF
  $ HGEDITOR="python cat.py" hg histedit --continue 2>&1 | fixbundle | grep -v '2 files removed'
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  d
  ***
  does not commute with e
  
  
  
  HG: Enter commit message.  Lines beginning with 'HG:' are removed.
  HG: Leave message empty to abort commit.
  HG: --
  HG: user: test
  HG: branch 'default'
  HG: changed d
  HG: changed e
  
  
  
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  merging e
  warning: conflicts during merge.
  merging e incomplete! (edit conflicts, then use 'hg resolve --mark')
  Fix up the change and run hg histedit --continue

just continue this time
  $ hg revert -r 'p1()' e
  $ hg resolve --mark e
  (no more unresolved files)
  $ hg histedit --continue 2>&1 | fixbundle
  7b4e2f4b7bcd: empty changeset
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved

log after edit
  $ hg log --graph
  @  changeset:   5:d9cf42e54966
  |  tag:         tip
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     f
  |
  o  changeset:   4:10486af2e984
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     d
  |
  o  changeset:   3:65a9a84f33fd
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     c
  |
  o  changeset:   2:da6535b52e45
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     b
  |
  o  changeset:   1:c1f09da44841
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     a
  |
  o  changeset:   0:1715188a53c7
     user:        test
     date:        Thu Jan 01 00:00:00 1970 +0000
     summary:     Initial commit
  

contents of e
  $ hg cat e
  I can haz no commute

manifest
  $ hg manifest
  a
  b
  c
  d
  e
  f

  $ cd ..

Repeat test using "roll", not "fold". "roll" folds in changes but drops message

  $ initrepo r2
  $ cd r2

Initial generation of the command files

  $ EDITED="$TESTTMP/editedhistory.2"
  $ hg log --template 'pick {node|short} {rev} {desc}\n' -r 3 >> $EDITED
  $ hg log --template 'pick {node|short} {rev} {desc}\n' -r 4 >> $EDITED
  $ hg log --template 'roll {node|short} {rev} {desc}\n' -r 7 >> $EDITED
  $ hg log --template 'pick {node|short} {rev} {desc}\n' -r 5 >> $EDITED
  $ hg log --template 'pick {node|short} {rev} {desc}\n' -r 6 >> $EDITED
  $ cat $EDITED
  pick 65a9a84f33fd 3 c
  pick 00f1c5383965 4 d
  roll 39522b764e3d 7 does not commute with e
  pick 7b4e2f4b7bcd 5 e
  pick 500cac37a696 6 f

log before edit
  $ hg log --graph
  @  changeset:   7:39522b764e3d
  |  tag:         tip
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     does not commute with e
  |
  o  changeset:   6:500cac37a696
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     f
  |
  o  changeset:   5:7b4e2f4b7bcd
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     e
  |
  o  changeset:   4:00f1c5383965
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     d
  |
  o  changeset:   3:65a9a84f33fd
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     c
  |
  o  changeset:   2:da6535b52e45
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     b
  |
  o  changeset:   1:c1f09da44841
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     a
  |
  o  changeset:   0:1715188a53c7
     user:        test
     date:        Thu Jan 01 00:00:00 1970 +0000
     summary:     Initial commit
  

edit the history
  $ hg histedit 3 --commands $EDITED 2>&1 | fixbundle
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  merging e
  warning: conflicts during merge.
  merging e incomplete! (edit conflicts, then use 'hg resolve --mark')
  Fix up the change and run hg histedit --continue

fix up
  $ echo 'I can haz no commute' > e
  $ hg resolve --mark e
  (no more unresolved files)
  $ hg histedit --continue 2>&1 | fixbundle | grep -v '2 files removed'
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  merging e
  warning: conflicts during merge.
  merging e incomplete! (edit conflicts, then use 'hg resolve --mark')
  Fix up the change and run hg histedit --continue

just continue this time
  $ hg revert -r 'p1()' e
  $ hg resolve --mark e
  (no more unresolved files)
  $ hg histedit --continue 2>&1 | fixbundle
  7b4e2f4b7bcd: empty changeset
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved

log after edit
  $ hg log --graph
  @  changeset:   5:e7c4f5d4eb75
  |  tag:         tip
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     f
  |
  o  changeset:   4:803d1bb561fc
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     d
  |
  o  changeset:   3:65a9a84f33fd
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     c
  |
  o  changeset:   2:da6535b52e45
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     b
  |
  o  changeset:   1:c1f09da44841
  |  user:        test
  |  date:        Thu Jan 01 00:00:00 1970 +0000
  |  summary:     a
  |
  o  changeset:   0:1715188a53c7
     user:        test
     date:        Thu Jan 01 00:00:00 1970 +0000
     summary:     Initial commit
  

contents of e
  $ hg cat e
  I can haz no commute

manifest
  $ hg manifest
  a
  b
  c
  d
  e
  f

description is taken from rollup target commit

  $ hg log --debug --rev 4
  changeset:   4:803d1bb561fceac3129ec778db9da249a3106fc3
  phase:       draft
  parent:      3:65a9a84f33fdeb1ad5679b3941ec885d2b24027b
  parent:      -1:0000000000000000000000000000000000000000
  manifest:    4:b068a323d969f22af1296ec6a5ea9384cef437ac
  user:        test
  date:        Thu Jan 01 00:00:00 1970 +0000
  files:       d e
  extra:       branch=default
  extra:       histedit_source=00f1c53839651fa5c76d423606811ea5455a79d0,39522b764e3d26103f08bd1fa2ccd3e3d7dbcf4e
  description:
  d
  
  

done with repo r2

  $ cd ..