view tests/test-copy-move-merge.t @ 44248:12491abf93bd stable

worker: manually buffer reads from pickle stream

My previous fix (D8051, cb52e619c99e, which added Python's built-in buffering
to the pickle stream) has the problem that the selector will ignore the buffer.
When multiple pickled objects are read from the pipe into the buffer at once,
only one object will be loaded.

This can repeat until the buffer is full and delays the processing of completed
items until the worker exits, at which point the pipe is always considered
readable and all remaining items are processed.

This changeset reverts D8051, removing the buffer again. Instead, on Python 3
only, we use a wrapper to modify the "read" provided to the Unpickler to behave
more like a buffered read. We never read more bytes from the pipe than the
Unpickler requests, so the selector behaves as expected.

Also add a test case for "pickle data was truncated" issue.

https://phab.mercurial-scm.org/D8051#119193

Differential Revision: https://phab.mercurial-scm.org/D8076

Test for the full copytracing algorithm
=======================================

  $ hg init t
  $ cd t

  $ echo 1 > a
  $ hg ci -qAm "first"

  $ hg cp a b
  $ hg mv a c
  $ echo 2 >> b
  $ echo 2 >> c

  $ hg ci -qAm "second"

  $ hg co -C 0
  1 files updated, 0 files merged, 2 files removed, 0 files unresolved

  $ echo 0 > a
  $ echo 1 >> a

  $ hg ci -qAm "other"

  $ hg merge --debug
    unmatched files in other:
     b
     c
    all copies found (* = to merge, ! = divergent, % = renamed and deleted):
     src: 'a' -> dst: 'b' *
     src: 'a' -> dst: 'c' *
    checking for directory renames
  resolving manifests
   branchmerge: True, force: False, partial: False
   ancestor: b8bf91eeebbc, local: add3f11052fa+, remote: 17c05bb7fcb6
   preserving a for resolve of b
   preserving a for resolve of c
  removing a
  starting 4 threads for background file closing (?)
   b: remote moved from a -> m (premerge)
  picked tool ':merge' for b (binary False symlink False changedelete False)
  merging a and b to b
  my b@add3f11052fa+ other b@17c05bb7fcb6 ancestor a@b8bf91eeebbc
   premerge successful
   c: remote moved from a -> m (premerge)
  picked tool ':merge' for c (binary False symlink False changedelete False)
  merging a and c to c
  my c@add3f11052fa+ other c@17c05bb7fcb6 ancestor a@b8bf91eeebbc
   premerge successful
  0 files updated, 2 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)

file b
  $ cat b
  0
  1
  2

file c
  $ cat c
  0
  1
  2

Test disabling copy tracing

- first verify copy metadata was kept

  $ hg up -qC 2
  $ hg rebase --keep -d 1 -b 2 --config extensions.rebase=
  rebasing 2:add3f11052fa "other" (tip)
  merging b and a to b
  merging c and a to c

  $ cat b
  0
  1
  2

- next verify copy metadata is lost when disabled

  $ hg strip -r . --config extensions.strip=
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  saved backup bundle to $TESTTMP/t/.hg/strip-backup/550bd84c0cd3-fc575957-backup.hg
  $ hg up -qC 2
  $ hg rebase --keep -d 1 -b 2 --config extensions.rebase= --config experimental.copytrace=off --config ui.interactive=True << EOF
  > c
  > EOF
  rebasing 2:add3f11052fa "other" (tip)
  file 'a' was deleted in local [dest] but was modified in other [source].
  You can use (c)hanged version, leave (d)eleted, or leave (u)nresolved.
  What do you want to do? c

  $ cat b
  1
  2

  $ cd ..

Verify disabling copy tracing still keeps copies from rebase source

  $ hg init copydisable
  $ cd copydisable
  $ touch a
  $ hg ci -Aqm 'add a'
  $ touch b
  $ hg ci -Aqm 'add b, c'
  $ hg cp b x
  $ echo x >> x
  $ hg ci -qm 'copy b->x'
  $ hg up -q 1
  $ touch z
  $ hg ci -Aqm 'add z'
  $ hg log -G -T '{rev} {desc}\n'
  @  3 add z
  |
  | o  2 copy b->x
  |/
  o  1 add b, c
  |
  o  0 add a
  
  $ hg rebase -d . -b 2 --config extensions.rebase= --config experimental.copytrace=off
  rebasing 2:6adcf8c12e7d "copy b->x"
  saved backup bundle to $TESTTMP/copydisable/.hg/strip-backup/6adcf8c12e7d-ce4b3e75-rebase.hg
  $ hg up -q 3
  $ hg log -f x -T '{rev} {desc}\n'
  3 copy b->x
  1 add b, c

  $ cd ../

Verify we duplicate existing copies, instead of detecting them

  $ hg init copydisable3
  $ cd copydisable3
  $ touch a
  $ hg ci -Aqm 'add a'
  $ hg cp a b
  $ hg ci -Aqm 'copy a->b'
  $ hg mv b c
  $ hg ci -Aqm 'move b->c'
  $ hg up -q 0
  $ hg cp a b
  $ echo b >> b
  $ hg ci -Aqm 'copy a->b (2)'
  $ hg log -G -T '{rev} {desc}\n'
  @  3 copy a->b (2)
  |
  | o  2 move b->c
  | |
  | o  1 copy a->b
  |/
  o  0 add a
  
  $ hg rebase -d 2 -s 3 --config extensions.rebase= --config experimental.copytrace=off
  rebasing 3:47e1a9e6273b "copy a->b (2)" (tip)
  saved backup bundle to $TESTTMP/copydisable3/.hg/strip-backup/47e1a9e6273b-2d099c59-rebase.hg

  $ hg log -G -f b
  @  changeset:   3:76024fb4b05b
  :  tag:         tip
  :  user:        test
  :  date:        Thu Jan 01 00:00:00 1970 +0000
  :  summary:     copy a->b (2)
  :
  o  changeset:   0:ac82d8b1f7c4
     user:        test
     date:        Thu Jan 01 00:00:00 1970 +0000
     summary:     add a