view tests/test-convert-baz.t @ 42406:f385ba70e4af

changelog: optionally store added and removed files in changeset extras

As mentioned in an earlier patch, copies._chain() is used a lot in the
changeset-centric version of pathcopies(). It is expensive because it
needs to look at the manifest in order to filter out copies whose
target file has since been removed. I want to store the sets of added
and removed files in the changeset in order to speed that up. This
patch does the writing part of that. It could easily be a separate
config, but it's currently tied to experimental.copies.write-to since
that's the only real use case (it will also make the {file_*} template
keywords faster, but I doubt that anyone cares enough about those to
write extra metadata for them).

The new information is stored in the changeset extras. Since they're
always subsets of the changeset's "files" list, they're stored as
indexes into that list. I've stored the indexes as stringified ints
separated by NUL bytes. The size of 00changelog.d for the hg repo
increased in size by 0.28% percent (compared to the size with only
copy information in the changesets, which in turn is 0.17% larger than
without copy information). We could store only the delta between the
indexes and we could store them in binary, but the chosen format is
more readable.

We could also have implemented this as a cache outside the
changelog. One advantage of doing it that way is that we would get the
speedups from the {file_*} template keywords also on old
repos. Another advantage is that it we can rewrite the cache if we
find a bug in how we calculate the set of files. A disadvantage is
that it would be more complex. Another is that it would surely use
more space. We already write the copy information to the changeset
extras, so it seems like a small step to also write these file sets.

Differential Revision: https://phab.mercurial-scm.org/D6416

#require baz symlink

  $ baz my-id "mercurial <[e-mail]>"

  $ 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)