view tests/test-rebase-emptycommit.t @ 42943:5fadf6103790

remotefilelog: replace repack lock to solve race condition

2c74337e6483 reduced the probability of race-conditions when starting
background repack and prefetch and we saw the difference in our CI instance
with all failures disappearing except one where one call to waitonrepack seems
to returns too early.

I'm not sure what exactly goes wrong but I realized that while the prefetch
operation uses a standard Mercurial lock, the repack operation is using a
custom lock based on `fcntl.flock` on available platforms. As `extutil.flock`
fallback on traditional Mercurial locks on other platforms and the tests are
stable on my laptop, our CI environment and GCC112, I'm sending this patch to
standardize the behavior across environments.

Differential Revision: https://phab.mercurial-scm.org/D6844

  $ cat >> $HGRCPATH<<EOF
  > [extensions]
  > rebase=
  > drawdag=$TESTDIR/drawdag.py
  > EOF

  $ hg init non-merge
  $ cd non-merge
  $ hg debugdrawdag<<'EOS'
  >   F
  >   |
  >   E
  >   |
  >   D
  >   |
  > B C
  > |/
  > A
  > EOS

  $ for i in C D E F; do
  >   hg bookmark -r $i -i BOOK-$i
  > done

  $ hg debugdrawdag<<'EOS'
  > E
  > |
  > D
  > |
  > B
  > EOS

  $ hg log -G -T '{rev} {desc} {bookmarks}'
  o  7 E
  |
  o  6 D
  |
  | o  5 F BOOK-F
  | |
  | o  4 E BOOK-E
  | |
  | o  3 D BOOK-D
  | |
  | o  2 C BOOK-C
  | |
  o |  1 B
  |/
  o  0 A
  
With --keep, bookmark should move

  $ hg rebase -r 3+4 -d E --keep
  rebasing 3:e7b3f00ed42e "D" (BOOK-D)
  note: not rebasing 3:e7b3f00ed42e "D" (BOOK-D), its destination already has all its changes
  rebasing 4:69a34c08022a "E" (BOOK-E)
  note: not rebasing 4:69a34c08022a "E" (BOOK-E), its destination already has all its changes
  $ hg log -G -T '{rev} {desc} {bookmarks}'
  o  7 E BOOK-D BOOK-E
  |
  o  6 D
  |
  | o  5 F BOOK-F
  | |
  | o  4 E
  | |
  | o  3 D
  | |
  | o  2 C BOOK-C
  | |
  o |  1 B
  |/
  o  0 A
  
Move D and E back for the next test

  $ hg bookmark BOOK-D -fqir 3
  $ hg bookmark BOOK-E -fqir 4

Bookmark is usually an indication of a head. For changes that are introduced by
an ancestor of bookmark B, after moving B to B-NEW, the changes are ideally
still introduced by an ancestor of changeset on B-NEW. In the below case,
"BOOK-D", and "BOOK-E" include changes introduced by "C".

  $ hg rebase -s 2 -d E
  rebasing 2:dc0947a82db8 "C" (BOOK-C C)
  rebasing 3:e7b3f00ed42e "D" (BOOK-D)
  note: not rebasing 3:e7b3f00ed42e "D" (BOOK-D), its destination already has all its changes
  rebasing 4:69a34c08022a "E" (BOOK-E)
  note: not rebasing 4:69a34c08022a "E" (BOOK-E), its destination already has all its changes
  rebasing 5:6b2aeab91270 "F" (BOOK-F F)
  saved backup bundle to $TESTTMP/non-merge/.hg/strip-backup/dc0947a82db8-52bb4973-rebase.hg
  $ hg log -G -T '{rev} {desc} {bookmarks}'
  o  5 F BOOK-F
  |
  o  4 C BOOK-C BOOK-D BOOK-E
  |
  o  3 E
  |
  o  2 D
  |
  o  1 B
  |
  o  0 A
  
Merge and its ancestors all become empty

  $ hg init $TESTTMP/merge1
  $ cd $TESTTMP/merge1

  $ hg debugdrawdag<<'EOS'
  >     E
  >    /|
  > B C D
  >  \|/
  >   A
  > EOS

  $ for i in C D E; do
  >   hg bookmark -r $i -i BOOK-$i
  > done

  $ hg debugdrawdag<<'EOS'
  > H
  > |
  > D
  > |
  > C
  > |
  > B
  > EOS

  $ hg rebase -r '(A::)-(B::)-A' -d H
  rebasing 2:dc0947a82db8 "C" (BOOK-C)
  note: not rebasing 2:dc0947a82db8 "C" (BOOK-C), its destination already has all its changes
  rebasing 3:b18e25de2cf5 "D" (BOOK-D)
  note: not rebasing 3:b18e25de2cf5 "D" (BOOK-D), its destination already has all its changes
  rebasing 4:86a1f6686812 "E" (BOOK-E E)
  note: not rebasing 4:86a1f6686812 "E" (BOOK-E E), its destination already has all its changes
  saved backup bundle to $TESTTMP/merge1/.hg/strip-backup/b18e25de2cf5-1fd0a4ba-rebase.hg

  $ hg log -G -T '{rev} {desc} {bookmarks}'
  o  4 H BOOK-C BOOK-D BOOK-E
  |
  o  3 D
  |
  o  2 C
  |
  o  1 B
  |
  o  0 A
  
Part of ancestors of a merge become empty

  $ hg init $TESTTMP/merge2
  $ cd $TESTTMP/merge2

  $ hg debugdrawdag<<'EOS'
  >     G
  >    /|
  >   E F
  >   | |
  > B C D
  >  \|/
  >   A
  > EOS

  $ for i in C D E F G; do
  >   hg bookmark -r $i -i BOOK-$i
  > done

  $ hg debugdrawdag<<'EOS'
  > H
  > |
  > F
  > |
  > C
  > |
  > B
  > EOS

  $ hg rebase -r '(A::)-(B::)-A' -d H
  rebasing 2:dc0947a82db8 "C" (BOOK-C)
  note: not rebasing 2:dc0947a82db8 "C" (BOOK-C), its destination already has all its changes
  rebasing 3:b18e25de2cf5 "D" (BOOK-D D)
  rebasing 4:03ca77807e91 "E" (BOOK-E E)
  rebasing 5:ad6717a6a58e "F" (BOOK-F)
  note: not rebasing 5:ad6717a6a58e "F" (BOOK-F), its destination already has all its changes
  rebasing 6:c58e8bdac1f4 "G" (BOOK-G G)
  saved backup bundle to $TESTTMP/merge2/.hg/strip-backup/b18e25de2cf5-2d487005-rebase.hg

  $ hg log -G -T '{rev} {desc} {bookmarks}'
  o    7 G BOOK-G
  |\
  | o  6 E BOOK-E
  | |
  o |  5 D BOOK-D BOOK-F
  |/
  o  4 H BOOK-C
  |
  o  3 F
  |
  o  2 C
  |
  o  1 B
  |
  o  0 A