tests/test-export.t

commit: improve the files field of changelog for merges

Currently, the files list of merge commits repeats all the deletions
(either actual deletions, or files that got renamed) that happened
between base and p2 of the merge. If p2 is the main branch, the list
can easily be much bigger than the change being merged.

This results in various problems worth improving:
- changelog is bigger than necessary
- `hg log directory` lists many unrelated merge commits, and `hg log
  -v -r commit` frequently fills multiple screens worth of files
- it possibly slows down adjustlinkrev, by forcing it to read more
  manifests, and that function can certainly be a bottleneck
- the server side of pulls can waste a lot of time simply opening the
  filelogs for pointless files (the constant factors for opening even
  a tiny filelog is apparently pretty bad)

So stop listing such files as described in the code.  Impacted merge
commits and their descendants get a different hash than they would
have without this. This doesn't seem problematic, except for
convert. The previous commit helped with that in the hg->hg case (but
if you do svn->hg twice from scratch, hashes can still change).

The rest of the description is numbers. I don't have much to report,
because recreating the files list of existing repositories is not
easy:
- debugupgradeformat and bundle/unbundle don't recreate the list
- export/import tends to choke quickly applying patches or on
  description that contain diffs,
- merge commits from the convert extension don't have the right files
  list for reasons orthogonal to the current commit
- replaying the merge with hg update/hg merge/hg revert --all/hg
  commit can end up failing in hg revert
- I wasn't sure that using debugsetparents + debugrebuilddirstate
  would really build the right thing

I measured commit time before and after this change, in a case with no
files filtered out, several files filtered out (no difference) and 5k
files filtered out (+1% time).

Recreating the 100 more recent merges in a private repo, the
concatenated uncompressed files lists goes from 1.12MB to
0.52MB. Excluding 3 merges that are not representative, then the size
goes from 570k to 15k.
I converted part of mozilla-central, and observed file list shrinking
quite a bit too, starting at the very first merge, 733641d9feaf, going
from 550 files to 10 files (although they have relatively few merges,
so they probably wouldn't care).

Differential Revision: https://phab.mercurial-scm.org/D6613

  $ hg init repo
  $ cd repo
  $ touch foo
  $ hg add foo
  $ for i in 0 1 2 3 4 5 6 7 8 9 10 11; do
  >    echo "foo-$i" >> foo
  >    hg ci -m "foo-$i"
  > done

  $ for out in "%nof%N" "%%%H" "%b-%R" "%h" "%r" "%m"; do
  >    echo
  >    echo "# foo-$out.patch"
  >    hg export -v -o "foo-$out.patch" 2:tip
  > done
  
  # foo-%nof%N.patch
  exporting patches:
  foo-01of10.patch
  foo-02of10.patch
  foo-03of10.patch
  foo-04of10.patch
  foo-05of10.patch
  foo-06of10.patch
  foo-07of10.patch
  foo-08of10.patch
  foo-09of10.patch
  foo-10of10.patch
  
  # foo-%%%H.patch
  exporting patches:
  foo-%617188a1c80f869a7b66c85134da88a6fb145f67.patch
  foo-%dd41a5ff707a5225204105611ba49cc5c229d55f.patch
  foo-%f95a5410f8664b6e1490a4af654e4b7d41a7b321.patch
  foo-%4346bcfde53b4d9042489078bcfa9c3e28201db2.patch
  foo-%afda8c3a009cc99449a05ad8aa4655648c4ecd34.patch
  foo-%35284ce2b6b99c9d2ac66268fe99e68e1974e1aa.patch
  foo-%9688c41894e6931305fa7165a37f6568050b4e9b.patch
  foo-%747d3c68f8ec44bb35816bfcd59aeb50b9654c2f.patch
  foo-%5f17a83f5fbd9414006a5e563eab4c8a00729efd.patch
  foo-%f3acbafac161ec68f1598af38f794f28847ca5d3.patch
  
  # foo-%b-%R.patch
  exporting patches:
  foo-repo-2.patch
  foo-repo-3.patch
  foo-repo-4.patch
  foo-repo-5.patch
  foo-repo-6.patch
  foo-repo-7.patch
  foo-repo-8.patch
  foo-repo-9.patch
  foo-repo-10.patch
  foo-repo-11.patch
  
  # foo-%h.patch
  exporting patches:
  foo-617188a1c80f.patch
  foo-dd41a5ff707a.patch
  foo-f95a5410f866.patch
  foo-4346bcfde53b.patch
  foo-afda8c3a009c.patch
  foo-35284ce2b6b9.patch
  foo-9688c41894e6.patch
  foo-747d3c68f8ec.patch
  foo-5f17a83f5fbd.patch
  foo-f3acbafac161.patch
  
  # foo-%r.patch
  exporting patches:
  foo-02.patch
  foo-03.patch
  foo-04.patch
  foo-05.patch
  foo-06.patch
  foo-07.patch
  foo-08.patch
  foo-09.patch
  foo-10.patch
  foo-11.patch
  
  # foo-%m.patch
  exporting patches:
  foo-foo_2.patch
  foo-foo_3.patch
  foo-foo_4.patch
  foo-foo_5.patch
  foo-foo_6.patch
  foo-foo_7.patch
  foo-foo_8.patch
  foo-foo_9.patch
  foo-foo_10.patch
  foo-foo_11.patch

Doing it again clobbers the files rather than appending:
  $ hg export -v -o "foo-%m.patch" 2:3
  exporting patches:
  foo-foo_2.patch
  foo-foo_3.patch
  $ grep HG foo-foo_2.patch | wc -l
  \s*1 (re)
  $ grep HG foo-foo_3.patch | wc -l
  \s*1 (re)

Using bookmarks:

  $ hg book -f -r 9 @
  $ hg book -f -r 11 test
  $ hg export -B test
  # HG changeset patch
  # User test
  # Date 0 0
  #      Thu Jan 01 00:00:00 1970 +0000
  # Node ID 5f17a83f5fbd9414006a5e563eab4c8a00729efd
  # Parent  747d3c68f8ec44bb35816bfcd59aeb50b9654c2f
  foo-10
  
  diff -r 747d3c68f8ec -r 5f17a83f5fbd foo
  --- a/foo	Thu Jan 01 00:00:00 1970 +0000
  +++ b/foo	Thu Jan 01 00:00:00 1970 +0000
  @@ -8,3 +8,4 @@
   foo-7
   foo-8
   foo-9
  +foo-10
  # HG changeset patch
  # User test
  # Date 0 0
  #      Thu Jan 01 00:00:00 1970 +0000
  # Node ID f3acbafac161ec68f1598af38f794f28847ca5d3
  # Parent  5f17a83f5fbd9414006a5e563eab4c8a00729efd
  foo-11
  
  diff -r 5f17a83f5fbd -r f3acbafac161 foo
  --- a/foo	Thu Jan 01 00:00:00 1970 +0000
  +++ b/foo	Thu Jan 01 00:00:00 1970 +0000
  @@ -9,3 +9,4 @@
   foo-8
   foo-9
   foo-10
  +foo-11

Exporting 4 changesets to a file:

  $ hg export -o export_internal 1 2 3 4
  $ grep HG export_internal | wc -l
  \s*4 (re)

Doing it again clobbers the file rather than appending:
  $ hg export -o export_internal 1 2 3 4
  $ grep HG export_internal | wc -l
  \s*4 (re)

Exporting 4 changesets to stdout:

  $ hg export 1 2 3 4 | grep HG | wc -l
  \s*4 (re)

Exporting revision -2 to a file:

  $ hg export -- -2
  # HG changeset patch
  # User test
  # Date 0 0
  #      Thu Jan 01 00:00:00 1970 +0000
  # Node ID 5f17a83f5fbd9414006a5e563eab4c8a00729efd
  # Parent  747d3c68f8ec44bb35816bfcd59aeb50b9654c2f
  foo-10
  
  diff -r 747d3c68f8ec -r 5f17a83f5fbd foo
  --- a/foo	Thu Jan 01 00:00:00 1970 +0000
  +++ b/foo	Thu Jan 01 00:00:00 1970 +0000
  @@ -8,3 +8,4 @@
   foo-7
   foo-8
   foo-9
  +foo-10

Exporting wdir revision:

  $ echo "foo-wdir" >> foo
  $ hg export 'wdir()'
  # HG changeset patch
  # User test
  # Date 0 0
  #      Thu Jan 01 00:00:00 1970 +0000
  # Node ID ffffffffffffffffffffffffffffffffffffffff
  # Parent  f3acbafac161ec68f1598af38f794f28847ca5d3
  
  
  diff -r f3acbafac161 foo
  --- a/foo	Thu Jan 01 00:00:00 1970 +0000
  +++ b/foo	Thu Jan 01 00:00:00 1970 +0000
  @@ -10,3 +10,4 @@
   foo-9
   foo-10
   foo-11
  +foo-wdir
  $ hg revert -q foo

Templated output to stdout:

  $ hg export -Tjson 0
  [
   {
    "branch": "default",
    "date": [0, 0],
    "desc": "foo-0",
    "diff": "diff -r 000000000000 -r 871558de6af2 foo\n--- /dev/null\tThu Jan 01 00:00:00 1970 +0000\n+++ b/foo\tThu Jan 01 00:00:00 1970 +0000\n@@ -0,0 +1,1 @@\n+foo-0\n",
    "node": "871558de6af2e8c244222f8eea69b782c94ce3df",
    "parents": [],
    "user": "test"
   }
  ]

Templated output to single file:

  $ hg export -Tjson 0:1 -o out.json
  $ cat out.json
  [
   {
    "branch": "default",
    "date": [0, 0],
    "desc": "foo-0",
    "diff": "diff -r 000000000000 -r 871558de6af2 foo\n--- /dev/null\tThu Jan 01 00:00:00 1970 +0000\n+++ b/foo\tThu Jan 01 00:00:00 1970 +0000\n@@ -0,0 +1,1 @@\n+foo-0\n",
    "node": "871558de6af2e8c244222f8eea69b782c94ce3df",
    "parents": [],
    "user": "test"
   },
   {
    "branch": "default",
    "date": [0, 0],
    "desc": "foo-1",
    "diff": "diff -r 871558de6af2 -r d1c9656e973c foo\n--- a/foo\tThu Jan 01 00:00:00 1970 +0000\n+++ b/foo\tThu Jan 01 00:00:00 1970 +0000\n@@ -1,1 +1,2 @@\n foo-0\n+foo-1\n",
    "node": "d1c9656e973cfb5aebd5499bbd2cb350e3b12266",
    "parents": ["871558de6af2e8c244222f8eea69b782c94ce3df"],
    "user": "test"
   }
  ]

Templated output to multiple files:

  $ hg export -Tjson 0:1 -o 'out-{rev}.json'
  $ cat out-0.json
  [
   {
    "branch": "default",
    "date": [0, 0],
    "desc": "foo-0",
    "diff": "diff -r 000000000000 -r 871558de6af2 foo\n--- /dev/null\tThu Jan 01 00:00:00 1970 +0000\n+++ b/foo\tThu Jan 01 00:00:00 1970 +0000\n@@ -0,0 +1,1 @@\n+foo-0\n",
    "node": "871558de6af2e8c244222f8eea69b782c94ce3df",
    "parents": [],
    "user": "test"
   }
  ]
  $ cat out-1.json
  [
   {
    "branch": "default",
    "date": [0, 0],
    "desc": "foo-1",
    "diff": "diff -r 871558de6af2 -r d1c9656e973c foo\n--- a/foo\tThu Jan 01 00:00:00 1970 +0000\n+++ b/foo\tThu Jan 01 00:00:00 1970 +0000\n@@ -1,1 +1,2 @@\n foo-0\n+foo-1\n",
    "node": "d1c9656e973cfb5aebd5499bbd2cb350e3b12266",
    "parents": ["871558de6af2e8c244222f8eea69b782c94ce3df"],
    "user": "test"
   }
  ]

Template keywrods:

  $ hg export 0 -T '# {node|shortest}\n\n{diff}'
  # 8715
  
  diff -r 000000000000 -r 871558de6af2 foo
  --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
  +++ b/foo	Thu Jan 01 00:00:00 1970 +0000
  @@ -0,0 +1,1 @@
  +foo-0

No filename should be printed if stdout is specified explicitly:

  $ hg export -v 1 -o -
  exporting patch:
  # HG changeset patch
  # User test
  # Date 0 0
  #      Thu Jan 01 00:00:00 1970 +0000
  # Node ID d1c9656e973cfb5aebd5499bbd2cb350e3b12266
  # Parent  871558de6af2e8c244222f8eea69b782c94ce3df
  foo-1
  
  diff -r 871558de6af2 -r d1c9656e973c foo
  --- a/foo	Thu Jan 01 00:00:00 1970 +0000
  +++ b/foo	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,1 +1,2 @@
   foo-0
  +foo-1

Checking if only alphanumeric characters are used in the file name (%m option):

  $ echo "line" >> foo
  $ hg commit -m " !\"#$%&(,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]"'^'"_\`abcdefghijklmnopqrstuvwxyz{|}~"
  $ hg export -v -o %m.patch tip
  exporting patch:
  ___________0123456789_______ABCDEFGHIJKLMNOPQRSTUVWXYZ______abcdefghijklmnopqrstuvwxyz____.patch

Template fragments in file name:

  $ hg export -v -o '{node|shortest}.patch' tip
  exporting patch:
  197e.patch

Backslash should be preserved because it is a directory separator on Windows:

  $ mkdir out
  $ hg export -v -o 'out\{node|shortest}.patch' tip
  exporting patch:
  out\197e.patch

Still backslash is taken as an escape character in inner template strings:

  $ hg export -v -o '{"out\{foo}.patch"}' tip
  exporting patch:
  out{foo}.patch

Invalid pattern in file name:

  $ hg export -o '%x.patch' tip
  abort: invalid format spec '%x' in output filename
  [255]
  $ hg export -o '%' tip
  abort: incomplete format spec in output filename
  [255]
  $ hg export -o '%{"foo"}' tip
  abort: incomplete format spec in output filename
  [255]
  $ hg export -o '%m{' tip
  hg: parse error at 3: unterminated template expansion
  (%m{
      ^ here)
  [255]
  $ hg export -o '%\' tip
  abort: invalid format spec '%\' in output filename
  [255]
  $ hg export -o '\%' tip
  abort: incomplete format spec in output filename
  [255]

Catch exporting unknown revisions (especially empty revsets, see issue3353)

  $ hg export
  # HG changeset patch
  # User test
  # Date 0 0
  #      Thu Jan 01 00:00:00 1970 +0000
  # Node ID 197ecd81a57f760b54f34a58817ad5b04991fa47
  # Parent  f3acbafac161ec68f1598af38f794f28847ca5d3
   !"#$%&(,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~
  
  diff -r f3acbafac161 -r 197ecd81a57f foo
  --- a/foo	Thu Jan 01 00:00:00 1970 +0000
  +++ b/foo	Thu Jan 01 00:00:00 1970 +0000
  @@ -10,3 +10,4 @@
   foo-9
   foo-10
   foo-11
  +line

  $ hg export ""
  hg: parse error: empty query
  [255]
  $ hg export 999
  abort: unknown revision '999'!
  [255]
  $ hg export "not all()"
  abort: export requires at least one changeset
  [255]

Check for color output
  $ cat <<EOF >> $HGRCPATH
  > [color]
  > mode = ansi
  > [extensions]
  > color =
  > EOF

  $ hg export --color always --nodates tip
  # HG changeset patch
  # User test
  # Date 0 0
  #      Thu Jan 01 00:00:00 1970 +0000
  # Node ID * (glob)
  # Parent * (glob)
   !"#$%&(,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}~
  
  \x1b[0;1mdiff -r f3acbafac161 -r 197ecd81a57f foo\x1b[0m (esc)
  \x1b[0;31;1m--- a/foo\x1b[0m (esc)
  \x1b[0;32;1m+++ b/foo\x1b[0m (esc)
  \x1b[0;35m@@ -10,3 +10,4 @@\x1b[0m (esc)
   foo-9
   foo-10
   foo-11
  \x1b[0;32m+line\x1b[0m (esc)


  $ cd ..