view tests/test-update-branches.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.

# Construct the following history tree:
#
# @  5:e1bb631146ca  b1
# |
# o  4:a4fdb3b883c4 0:b608b9236435  b1
# |
# | o  3:4b57d2520816 1:44592833ba9f
# | |
# | | o  2:063f31070f65
# | |/
# | o  1:44592833ba9f
# |/
# o  0:b608b9236435

  $ mkdir b1
  $ cd b1
  $ hg init
  $ echo foo > foo
  $ echo zero > a
  $ hg init sub
  $ echo suba > sub/suba
  $ hg --cwd sub ci -Am addsuba
  adding suba
  $ echo 'sub = sub' > .hgsub
  $ hg ci -qAm0
  $ echo one > a ; hg ci -m1
  $ echo two > a ; hg ci -m2
  $ hg up -q 1
  $ echo three > a ; hg ci -qm3
  $ hg up -q 0
  $ hg branch -q b1
  $ echo four > a ; hg ci -qm4
  $ echo five > a ; hg ci -qm5

Initial repo state:

  $ hg log -G --template '{rev}:{node|short} {parents} {branches}\n'
  @  5:ff252e8273df  b1
  |
  o  4:d047485b3896 0:60829823a42a  b1
  |
  | o  3:6efa171f091b 1:0786582aa4b1
  | |
  | | o  2:bd10386d478c
  | |/
  | o  1:0786582aa4b1
  |/
  o  0:60829823a42a
  

Make sure update doesn't assume b1 is a repository if invoked from outside:

  $ cd ..
  $ hg update b1
  abort: no repository found in '$TESTTMP' (.hg not found)!
  [255]
  $ cd b1

Test helper functions:

  $ revtest () {
  >     msg=$1
  >     dirtyflag=$2   # 'clean', 'dirty' or 'dirtysub'
  >     startrev=$3
  >     targetrev=$4
  >     opt=$5
  >     hg up -qC $startrev
  >     test $dirtyflag = dirty && echo dirty > foo
  >     test $dirtyflag = dirtysub && echo dirty > sub/suba
  >     hg up $opt $targetrev
  >     hg parent --template 'parent={rev}\n'
  >     hg stat -S
  > }

  $ norevtest () {
  >     msg=$1
  >     dirtyflag=$2   # 'clean', 'dirty' or 'dirtysub'
  >     startrev=$3
  >     opt=$4
  >     hg up -qC $startrev
  >     test $dirtyflag = dirty && echo dirty > foo
  >     test $dirtyflag = dirtysub && echo dirty > sub/suba
  >     hg up $opt
  >     hg parent --template 'parent={rev}\n'
  >     hg stat -S
  > }

Test cases are documented in a table in the update function of merge.py.
Cases are run as shown in that table, row by row.

  $ norevtest 'none clean linear' clean 4
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  parent=5

  $ norevtest 'none clean same'   clean 2
  abort: not a linear update
  (merge or update --check to force update)
  parent=2


  $ revtest 'none clean linear' clean 1 2
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  parent=2

  $ revtest 'none clean same'   clean 2 3
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  parent=3

  $ revtest 'none clean cross'  clean 3 4
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  parent=4


  $ revtest 'none dirty linear' dirty 1 2
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  parent=2
  M foo

  $ revtest 'none dirtysub linear' dirtysub 1 2
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  parent=2
  M sub/suba

  $ revtest 'none dirty same'   dirty 2 3
  abort: uncommitted changes
  (commit or update --clean to discard changes)
  parent=2
  M foo

  $ revtest 'none dirtysub same'   dirtysub 2 3
  abort: uncommitted changes
  (commit or update --clean to discard changes)
  parent=2
  M sub/suba

  $ revtest 'none dirty cross'  dirty 3 4
  abort: uncommitted changes
  (commit or update --clean to discard changes)
  parent=3
  M foo

  $ norevtest 'none dirty cross'  dirty 2
  abort: uncommitted changes
  (commit and merge, or update --clean to discard changes)
  parent=2
  M foo

  $ revtest 'none dirtysub cross'  dirtysub 3 4
  abort: uncommitted changes
  (commit or update --clean to discard changes)
  parent=3
  M sub/suba

  $ revtest '-C dirty linear'   dirty 1 2 -C
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  parent=2

  $ revtest '-c dirty linear'   dirty 1 2 -c
  abort: uncommitted changes
  parent=1
  M foo

  $ revtest '-c dirtysub linear'   dirtysub 1 2 -c
  abort: uncommitted changes in subrepository 'sub'
  parent=1
  M sub/suba

  $ norevtest '-c clean same'   clean 2 -c
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  parent=3

  $ revtest '-cC dirty linear'  dirty 1 2 -cC
  abort: cannot specify both -c/--check and -C/--clean
  parent=1
  M foo

Test obsolescence behavior
---------------------------------------------------------------------

successors should be taken in account when checking head destination

  $ cat << EOF >> $HGRCPATH
  > [ui]
  > logtemplate={rev}:{node|short} {desc|firstline}
  > [experimental]
  > evolution=createmarkers
  > EOF

Test no-argument update to a successor of an obsoleted changeset

  $ hg log -G
  o  5:ff252e8273df 5
  |
  o  4:d047485b3896 4
  |
  | o  3:6efa171f091b 3
  | |
  | | o  2:bd10386d478c 2
  | |/
  | @  1:0786582aa4b1 1
  |/
  o  0:60829823a42a 0
  
  $ hg book bm -r 3
  $ hg status
  M foo

We add simple obsolescence marker between 3 and 4 (indirect successors)

  $ hg id --debug -i -r 3
  6efa171f091b00a3c35edc15d48c52a498929953
  $ hg id --debug -i -r 4
  d047485b3896813b2a624e86201983520f003206
  $ hg debugobsolete 6efa171f091b00a3c35edc15d48c52a498929953 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
  $ hg debugobsolete aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa d047485b3896813b2a624e86201983520f003206

Test that 5 is detected as a valid destination from 3 and also accepts moving
the bookmark (issue4015)

  $ hg up --quiet --hidden 3
  $ hg up 5
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg book bm
  moving bookmark 'bm' forward from 6efa171f091b
  $ hg bookmarks
   * bm                        5:ff252e8273df

Test that 4 is detected as the no-argument destination from 3 and also moves
the bookmark with it
  $ hg up --quiet 0          # we should be able to update to 3 directly
  $ hg up --quiet --hidden 3 # but not implemented yet.
  $ hg book -f bm
  $ hg up
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  updating bookmark bm
  $ hg book
   * bm                        4:d047485b3896

Test that 5 is detected as a valid destination from 1
  $ hg up --quiet 0          # we should be able to update to 3 directly
  $ hg up --quiet --hidden 3 # but not implemented yet.
  $ hg up 5
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

Test that 5 is not detected as a valid destination from 2
  $ hg up --quiet 0
  $ hg up --quiet 2
  $ hg up 5
  abort: uncommitted changes
  (commit or update --clean to discard changes)
  [255]

Test that we don't crash when updating from a pruned changeset (i.e. has no
successors). Behavior should probably be that we update to the first
non-obsolete parent but that will be decided later.
  $ hg id --debug -r 2
  bd10386d478cd5a9faf2e604114c8e6da62d3889
  $ hg up --quiet 0
  $ hg up --quiet 2
  $ hg debugobsolete bd10386d478cd5a9faf2e604114c8e6da62d3889
  $ hg up
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved