tests/test-rename-rev.t
author Arun Kulshreshtha <akulshreshtha@janestreet.com>
Tue, 30 Aug 2022 15:29:55 -0400
changeset 49491 c6a1beba27e9
parent 48247 c62e4397eb28
permissions -rw-r--r--
bisect: avoid copying ancestor list for non-merge commits During a bisection, hg needs to compute a list of all ancestors for every candidate commit. This is accomplished via a bottom-up traversal of the set of candidates, during which each revision's ancestor list is populated using the ancestor list of its parent(s). Previously, this involved copying the entire list, which could be very long in if the bisection range was large. To help improve this, we can observe that each candidate commit is visited exactly once, at which point its ancestor list is copied into its children's lists and then dropped. In the case of non-merge commits, a commit's ancestor list consists exactly of its parent's list plus itself. This means that we can trivially reuse the parent's existing list for one of its non-merge children, which avoids copying entirely if that commit is the parent's only child. This makes bisections over linear ranges of commits much faster. During some informal testing in the large publicly-available `mozilla-central` repository, this noticeably sped up bisections over large ranges of history: Setup: $ cd mozilla-central $ hg bisect --reset $ hg bisect --good 0 $ hg log -r tip -T '{rev}\n' 628417 Test: $ time hg bisect --bad tip --noupdate Before: real 3m35.927s user 3m35.553s sys 0m0.319s After: real 1m41.142s user 1m40.810s sys 0m0.285s

  $ hg init
  $ mkdir d1 d1/d11 d2
  $ echo d1/a > d1/a
  $ echo d1/ba > d1/ba
  $ echo d1/a1 > d1/d11/a1
  $ echo d1/b > d1/b
  $ echo d2/b > d2/b
  $ hg add d1/a d1/b d1/ba d1/d11/a1 d2/b
  $ hg commit -m "intial"


Test single file

# One recorded copy, one copy to record after commit
  $ hg cp d1/b d1/c
  $ cp d1/b d1/d
  $ hg add d1/d
  $ hg ci -m 'copy d1/b to d1/c and d1/d'
  $ hg st -C --change .
  A d1/c
    d1/b
  A d1/d
# Errors out without --after for now
  $ hg cp --at-rev . d1/b d1/d
  abort: --at-rev requires --after
  [10]
# Errors out with non-existent source
  $ hg cp -A --at-rev . d1/non-existent d1/d
  d1/non-existent: no such file in rev 55d1fd85ef0a
  abort: no files to copy
  [10]
# Errors out with non-existent destination
  $ hg cp -A --at-rev . d1/b d1/non-existent
  abort: d1/non-existent: copy destination does not exist in 8a9d70fa20c9
  [10]
# Successful invocation
  $ hg cp -A --at-rev . d1/b d1/d
  saved backup bundle to $TESTTMP/.hg/strip-backup/8a9d70fa20c9-973ae357-copy.hg
# New copy is recorded, and previously recorded copy is also still there
  $ hg st -C --change .
  A d1/c
    d1/b
  A d1/d
    d1/b
# Should get helpful message if we try to copy or rename after commit
  $ hg cp --forget --at-rev . d1/d
  saved backup bundle to $TESTTMP/.hg/strip-backup/3f7c325d3f9e-46f377bb-uncopy.hg
  $ hg cp d1/b d1/d
  d1/d: not overwriting - file already committed
  ('hg copy --at-rev .' to record the copy in the parent of the working copy)
  [1]
  $ hg mv d1/b d1/d
  d1/d: not overwriting - file already committed
  ('hg rename --at-rev .' to record the rename in the parent of the working copy)
  [1]

Test moved file (not copied) using 'hg cp' command

  $ hg co 0
  0 files updated, 0 files merged, 2 files removed, 0 files unresolved
  $ mv d1/b d1/d
  $ hg rm -A d1/b
  $ hg add d1/d
  $ hg ci -m 'move d1/b to d1/d'
  created new head
  $ hg cp -A --at-rev . d1/b d1/d
  saved backup bundle to $TESTTMP/.hg/strip-backup/519850c3ea27-153c8fbb-copy.hg
  $ hg st -C --change .
  A d1/d
    d1/b
  R d1/b

Test moved file (not copied) using 'hg mv' command

  $ hg co 0
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ mv d1/b d1/d
  $ hg rm -A d1/b
  $ hg add d1/d
  $ hg ci -m 'move d1/b to d1/d'
  created new head
  $ hg mv -A --at-rev . d1/b d1/d
  saved backup bundle to $TESTTMP/.hg/strip-backup/519850c3ea27-153c8fbb-copy.hg
  $ hg st -C --change .
  A d1/d
    d1/b
  R d1/b

Test moved file (not copied) for which source still exists

  $ hg co 0
  1 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ cp d1/b d1/d
  $ hg add d1/d
  $ hg ci -m 'copy d1/b to d1/d'
  created new head
  $ hg mv -A --at-rev . d1/b d1/d
  saved backup bundle to $TESTTMP/.hg/strip-backup/c8d0f6bcf7ca-1c9bb53e-copy.hg
  $ hg st -C --change .
  A d1/d
    d1/b

Test using directory as destination

  $ hg co 0
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ cp -R d1 d3
  $ hg add d3
  adding d3/a
  adding d3/b
  adding d3/ba
  adding d3/d11/a1
  $ hg ci -m 'copy d1/ to d3/'
  created new head
  $ hg cp -A --at-rev . d1 d3
  abort: d3: --at-rev does not support a directory as destination
  [10]