tests/test-convert-baz.t
author Arun Kulshreshtha <akulshreshtha@janestreet.com>
Tue, 30 Aug 2022 15:29:55 -0400
changeset 49491 c6a1beba27e9
parent 30888 561a019c0268
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

#require baz symlink

  $ baz my-id "mercurial <mercurial@mercurial-scm.org>"

  $ echo "[extensions]" >> $HGRCPATH
  $ echo "convert=" >> $HGRCPATH

create baz archive
  $ baz make-archive baz@mercurial--convert hg-test-convert-baz

initialize baz repo
  $ mkdir baz-repo
  $ cd baz-repo/
  $ baz init-tree baz@mercurial--convert/baz--test--0
  $ baz import
  * creating version baz@mercurial--convert/baz--test--0
  * imported baz@mercurial--convert/baz--test--0

create initial files
  $ echo 'this is a file' > a
  $ baz add a
  $ mkdir src
  $ baz add src
  $ cd src
  $ dd count=1 if=/dev/zero of=b > /dev/null 2> /dev/null
  $ baz add b
HACK: hide GNU tar-1.22 "tar: The --preserve option is deprecated, use --preserve-permissions --preserve-order instead"
  $ baz commit -s "added a file, src and src/b (binary)" 2>&1 | grep -v '^tar'
  * build pristine tree for baz@mercurial--convert/baz--test--0--base-0
  * Scanning for full-tree revision: .
  * from import revision: baz@mercurial--convert/baz--test--0--base-0
  A/ .arch-ids
  A/ src
  A/ src/.arch-ids
  A  .arch-ids/a.id
  A  a
  A  src/.arch-ids/=id
  A  src/.arch-ids/b.id
  A  src/b
  * update pristine tree (baz@mercurial--convert/baz--test--0--base-0 => baz--test--0--patch-1)
  * committed baz@mercurial--convert/baz--test--0--patch-1

create link file and modify a
  $ ln -s ../a a-link
  $ baz add a-link
  $ echo 'this a modification to a' >> ../a
  $ baz commit -s "added link to a and modify a"
  A  src/.arch-ids/a-link.id
  A  src/a-link
  M  a
  * update pristine tree (baz@mercurial--convert/baz--test--0--patch-1 => baz--test--0--patch-2)
  * committed baz@mercurial--convert/baz--test--0--patch-2

create second link and modify b
  $ ln -s ../a a-link-2
  $ baz add a-link-2
  $ dd count=1 seek=1 if=/dev/zero of=b > /dev/null 2> /dev/null
  $ baz commit -s "added second link and modify b"
  A  src/.arch-ids/a-link-2.id
  A  src/a-link-2
  Mb src/b
  * update pristine tree (baz@mercurial--convert/baz--test--0--patch-2 => baz--test--0--patch-3)
  * committed baz@mercurial--convert/baz--test--0--patch-3

b file to link and a-link-2 to regular file
  $ rm -f a-link-2
  $ echo 'this is now a regular file' > a-link-2
  $ ln -sf ../a b
  $ baz commit -s "file to link and link to file test"
  fl src/b
  lf src/a-link-2
  * update pristine tree (baz@mercurial--convert/baz--test--0--patch-3 => baz--test--0--patch-4)
  * committed baz@mercurial--convert/baz--test--0--patch-4

move a-link-2 file and src directory
  $ cd ..
  $ baz mv src/a-link-2 c
  $ baz mv src test
  $ baz commit -s "move and rename a-link-2 file and src directory"
  D/ src/.arch-ids
  A/ test/.arch-ids
  /> src	test
  => src/.arch-ids/a-link-2.id	.arch-ids/c.id
  => src/a-link-2	c
  => src/.arch-ids/=id	test/.arch-ids/=id
  => src/.arch-ids/a-link.id	test/.arch-ids/a-link.id
  => src/.arch-ids/b.id	test/.arch-ids/b.id
  * update pristine tree (baz@mercurial--convert/baz--test--0--patch-4 => baz--test--0--patch-5)
  * committed baz@mercurial--convert/baz--test--0--patch-5

move and add the moved file again
  $ echo e > e
  $ baz add e
  $ baz commit -s "add e"
  A  .arch-ids/e.id
  A  e
  * update pristine tree (baz@mercurial--convert/baz--test--0--patch-5 => baz--test--0--patch-6)
  * committed baz@mercurial--convert/baz--test--0--patch-6
  $ baz mv e f
  $ echo ee > e
  $ baz add e
  $ baz commit -s "move e and recreate it again"
  A  .arch-ids/e.id
  A  e
  => .arch-ids/e.id	.arch-ids/f.id
  => e	f
  * update pristine tree (baz@mercurial--convert/baz--test--0--patch-6 => baz--test--0--patch-7)
  * committed baz@mercurial--convert/baz--test--0--patch-7
  $ cd ..

converting baz repo to Mercurial
  $ hg convert baz-repo baz-repo-hg
  initializing destination baz-repo-hg repository
  analyzing tree version baz@mercurial--convert/baz--test--0...
  scanning source...
  sorting...
  converting...
  7 initial import
  6 added a file, src and src/b (binary)
  5 added link to a and modify a
  4 added second link and modify b
  3 file to link and link to file test
  2 move and rename a-link-2 file and src directory
  1 add e
  0 move e and recreate it again

  $ baz register-archive -d baz@mercurial--convert

  $ glog()
  > {
  >     hg log -G --template '{rev} "{desc|firstline}" files: {files}\n' "$@"
  > }

show graph log
  $ glog -R baz-repo-hg
  o  7 "move e and recreate it again" files: e f
  |
  o  6 "add e" files: e
  |
  o  5 "move and rename a-link-2 file and src directory" files: c src/a-link src/a-link-2 src/b test/a-link test/b
  |
  o  4 "file to link and link to file test" files: src/a-link-2 src/b
  |
  o  3 "added second link and modify b" files: src/a-link-2 src/b
  |
  o  2 "added link to a and modify a" files: a src/a-link
  |
  o  1 "added a file, src and src/b (binary)" files: a src/b
  |
  o  0 "initial import" files:
  
  $ hg up -q -R baz-repo-hg
  $ hg -R baz-repo-hg manifest --debug
  c4072c4b72e1cabace081888efa148ee80ca3cbb 644   a
  0201ac32a3a8e86e303dff60366382a54b48a72e 644   c
  1a4a864db0073705a11b1439f563bfa4b46d9246 644   e
  09e0222742fc3f75777fa9d68a5d8af7294cb5e7 644   f
  c0067ba5ff0b7c9a3eb17270839d04614c435623 644 @ test/a-link
  375f4263d86feacdea7e3c27100abd1560f2a973 644 @ test/b
  $ hg -R baz-repo-hg log -r 5 -r 7 -C --debug | grep copies
  copies:      c (src/a-link-2) test/a-link (src/a-link) test/b (src/b)
  copies:      f (e)