comparison tests/test-convert-git.t @ 30660:1f21a6835604

convert: add config option to copy extra keys from Git commits

Git commit objects support storing arbitrary key-value metadata. While
there is no user-facing mechanism in Git to record these values, some
tools do record data here.

Currently, `hg convert` only handles the "author," "committer," and
"parent" keys in Git commit objects. All other keys are ignored. This
means that any custom keys are lost when converting Git repos to
Mercurial.

This patch implements support for copying a whitelist of extra keys
from Git commit objects to the "extras" dict of the destination. As
the added tests demonstate, this allows extra metadata to be preserved
during the conversion process.

This patch stops short of converting all metadata to "extras." We could
potentially implement this via `convert.git.extrakeys=*` or similar.
But copying everything by default is a bit dangerous because if Git
adds new keys to commit objects, we could find ourselves copying
things that shouldn't be copied!

This patch also assumes the source key is the same as the destination
key. We could implement support for prefixing the output key to
distinguish it as coming from Git. But until this feature is needed,
I'm inclined to hold off implementing it.

30659:1404146157d9

  $ test -f GIT-EXT-COMMAND-INJECTION
  [1]

#endif

30660:1f21a6835604

  $ test -f GIT-EXT-COMMAND-INJECTION
  [1]

#endif

Conversion of extra commit metadata to extras works

  $ git init gitextras >/dev/null 2>/dev/null
  $ cd gitextras
  $ touch foo
  $ git add foo
  $ commit -m initial
  $ echo 1 > foo
  $ tree=`git write-tree`

Git doesn't provider a user-facing API to write extra metadata into the
commit, so create the commit object by hand

  $ git hash-object -t commit -w --stdin << EOF
  > tree ${tree}
  > parent ba6b1344e977ece9e00958dbbf17f1f09384b2c1
  > author test <[e-mail]> 1000000000 +0000
  > committer test <[e-mail]> 1000000000 +0000
  > extra-1 extra-1
  > extra-2 extra-2 with space
  > convert_revision 0000aaaabbbbccccddddeeee
  > 
  > message with extras
  > EOF
  8123727c8361a4117d1a2d80e0c4e7d70c757f18

  $ git reset --hard 8123727c8361a4117d1a2d80e0c4e7d70c757f18 > /dev/null

  $ cd ..

convert will not retain custom metadata keys by default

  $ hg convert gitextras hgextras1
  initializing destination hgextras1 repository
  scanning source...
  sorting...
  converting...
  1 initial
  0 message with extras
  updating bookmarks

  $ hg -R hgextras1 log --debug -r 1
  changeset:   1:e13a39880f68479127b2a80fa0b448cc8524aa09
  bookmark:    master
  tag:         tip
  phase:       draft
  parent:      0:dcb68977c55cd02cbd13b901df65c4b6e7b9c4b9
  parent:      -1:0000000000000000000000000000000000000000
  manifest:    0:6a3df4de388f3c4f8e28f4f9a814299a3cbb5f50
  user:        test <[e-mail]>
  date:        Sun Sep 09 01:46:40 2001 +0000
  extra:       branch=default
  extra:       convert_revision=8123727c8361a4117d1a2d80e0c4e7d70c757f18
  description:
  message with extras
  
  

Attempting to convert a banned extra is disallowed

  $ hg convert --config convert.git.extrakeys=tree,parent gitextras hgextras-banned
  initializing destination hgextras-banned repository
  abort: copying of extra key is forbidden: parent, tree
  [255]

Converting a specific extra works

  $ hg convert --config convert.git.extrakeys=extra-1 gitextras hgextras2
  initializing destination hgextras2 repository
  scanning source...
  sorting...
  converting...
  1 initial
  0 message with extras
  updating bookmarks

  $ hg -R hgextras2 log --debug -r 1
  changeset:   1:d40fb205d58597e6ecfd55b16f198be5bf436391
  bookmark:    master
  tag:         tip
  phase:       draft
  parent:      0:dcb68977c55cd02cbd13b901df65c4b6e7b9c4b9
  parent:      -1:0000000000000000000000000000000000000000
  manifest:    0:6a3df4de388f3c4f8e28f4f9a814299a3cbb5f50
  user:        test <[e-mail]>
  date:        Sun Sep 09 01:46:40 2001 +0000
  extra:       branch=default
  extra:       convert_revision=8123727c8361a4117d1a2d80e0c4e7d70c757f18
  extra:       extra-1=extra-1
  description:
  message with extras
  
  

Converting multiple extras works

  $ hg convert --config convert.git.extrakeys=extra-1,extra-2 gitextras hgextras3
  initializing destination hgextras3 repository
  scanning source...
  sorting...
  converting...
  1 initial
  0 message with extras
  updating bookmarks

  $ hg -R hgextras3 log --debug -r 1
  changeset:   1:0105af33379e7b6491501fd34141b7af700fe125
  bookmark:    master
  tag:         tip
  phase:       draft
  parent:      0:dcb68977c55cd02cbd13b901df65c4b6e7b9c4b9
  parent:      -1:0000000000000000000000000000000000000000
  manifest:    0:6a3df4de388f3c4f8e28f4f9a814299a3cbb5f50
  user:        test <[e-mail]>
  date:        Sun Sep 09 01:46:40 2001 +0000
  extra:       branch=default
  extra:       convert_revision=8123727c8361a4117d1a2d80e0c4e7d70c757f18
  extra:       extra-1=extra-1
  extra:       extra-2=extra-2 with space
  description:
  message with extras