filemerge: add support for partial conflict resolution by external tool
A common class of merge conflicts is in imports/#includes/etc. It's
relatively easy to write a tool that can resolve these conflicts,
perhaps by naively just unioning the statements and leaving any
cleanup to other tools to do later [1]. Such specialized tools cannot
generally resolve all conflicts in a file, of course. Let's therefore
call them "partial merge tools". Note that the internal simplemerge
algorithm is such a partial merge tool - one that only resolves
trivial "conflicts" where one side is unchanged or both sides change
in the same way.
One can also imagine having smarter language-aware partial tools that
merge the AST. It may be useful for such tools to interactively let
the user resolve any conflicts it can't resolve itself. However,
having the option of implementing it as a partial merge tool means
that the developer doesn't *need* to create a UI for it. Instead, the
user can resolve any remaining conflicts with their regular merge tool
(e.g. `:merge3` or `meld).
We don't currently have a way to let the user define such partial
merge tools. That's what this patch addresses. It lets the user
configure partial merge tools to run. Each tool can be configured to
run only on files matching certain patterns (e.g. "*.py"). The tool
takes three inputs (local, base, other) and resolves conflicts by
updating these in place. For example, let's say the inputs are these:
base:
```
import sys
def main():
print('Hello')
```
local:
```
import os
import sys
def main():
print('Hi')
```
other:
```
import re
import sys
def main():
print('Howdy')
```
A partial merge tool could now resolve the conflicting imports by
replacing the import statements in *all* files by the following
snippet, while leaving the remainder of the files unchanged.
```
import os
import re
import sys
```
As a result, simplemerge and any regular merge tool that runs after
the partial merge tool(s) will consider the imports to be
non-conflicting and will only present the conflict in `main()` to the
user.
Differential Revision: https://phab.mercurial-scm.org/D12356
$ cat >> $HGRCPATH <<EOF
> [extensions]
> convert=
> [convert]
> hg.saverev=False
> EOF
$ hg init orig
$ cd orig
$ echo foo > foo
$ echo bar > bar
$ hg ci -qAm 'add foo and bar'
$ hg rm foo
$ hg ci -m 'remove foo'
$ mkdir foo
$ echo file > foo/file
$ hg ci -qAm 'add foo/file'
$ hg tag some-tag
$ hg tag -l local-tag
$ echo '1234567890123456789012345678901234567890 missing_tag' >> .hgtags
$ hg ci -m 'add a missing tag'
$ hg log
changeset: 4:3fb95ee23a66
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: add a missing tag
changeset: 3:593cbf6fb2b4
tag: local-tag
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Added tag some-tag for changeset ad681a868e44
changeset: 2:ad681a868e44
tag: some-tag
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: add foo/file
changeset: 1:cbba8ecc03b7
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: remove foo
changeset: 0:327daa9251fa
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: add foo and bar
$ hg phase --public -r tip
$ cd ..
$ hg convert orig new 2>&1 | grep -v 'subversion python bindings could not be loaded'
initializing destination new repository
scanning source...
sorting...
converting...
4 add foo and bar
3 remove foo
2 add foo/file
1 Added tag some-tag for changeset ad681a868e44
0 add a missing tag
missing tag entry: "1234567890123456789012345678901234567890 missing_tag"
$ cd new
$ hg log -G --template '{rev} {node|short} ({phase}) "{desc}"\n'
o 4 3fb95ee23a66 (public) "add a missing tag"
|
o 3 593cbf6fb2b4 (public) "Added tag some-tag for changeset ad681a868e44"
|
o 2 ad681a868e44 (public) "add foo/file"
|
o 1 cbba8ecc03b7 (public) "remove foo"
|
o 0 327daa9251fa (public) "add foo and bar"
$ hg out ../orig
comparing with ../orig
searching for changes
no changes found
[1]
dirstate should be empty:
$ hg debugstate
$ hg parents -q
$ hg up -C
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg copy bar baz
put something in the dirstate:
$ hg debugstate > debugstate
$ grep baz debugstate
a 0 -1 unset baz
copy: bar -> baz
add a new revision in the original repo
$ cd ../orig
$ echo baz > baz
$ hg ci -qAm 'add baz'
$ cd ..
$ hg convert orig new 2>&1 | grep -v 'subversion python bindings could not be loaded'
scanning source...
sorting...
converting...
0 add baz
$ cd new
$ hg out ../orig
comparing with ../orig
searching for changes
no changes found
[1]
dirstate should be the same (no output below):
$ hg debugstate > new-debugstate
$ diff debugstate new-debugstate
no copies
$ hg up -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg debugrename baz
baz not renamed
$ cd ..
test tag rewriting
$ cat > filemap <<EOF
> exclude foo
> EOF
$ hg convert --filemap filemap orig new-filemap 2>&1 | grep -v 'subversion python bindings could not be loaded'
initializing destination new-filemap repository
scanning source...
sorting...
converting...
5 add foo and bar
4 remove foo
3 add foo/file
2 Added tag some-tag for changeset ad681a868e44
1 add a missing tag
missing tag entry: "1234567890123456789012345678901234567890 missing_tag"
0 add baz
$ cd new-filemap
$ hg tags
tip 3:7bb553f2c68a
some-tag 0:ba8636729451
$ cd ..
Test cases for hg-hg roundtrip
Helper
$ glog()
> {
> hg log -G --template '{rev} {node|short} ({phase}) "{desc}" files: {files}\n' $*
> }
Create a tricky source repo
$ hg init source
$ cd source
$ echo 0 > 0
$ hg ci -Aqm '0: add 0'
$ echo a > a
$ mkdir dir
$ echo b > dir/b
$ hg ci -qAm '1: add a and dir/b'
$ echo c > dir/c
$ hg ci -qAm '2: add dir/c'
$ hg copy a e
$ echo b >> b
$ hg ci -qAm '3: copy a to e, change b'
$ hg up -qr -3
$ echo a >> a
$ hg ci -qAm '4: change a'
$ hg merge
merging a and e to e
2 files updated, 1 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg copy b dir/d
$ hg ci -qAm '5: merge 2 and 3, copy b to dir/d'
$ echo a >> a
$ hg ci -qAm '6: change a'
$ hg mani
0
a
b
dir/b
dir/c
dir/d
e
$ hg phase --public -r tip
$ glog
@ 6 0613c8e59a3d (public) "6: change a" files: a
|
o 5 717e9b37cdb7 (public) "5: merge 2 and 3, copy b to dir/d" files: dir/d e
|\
| o 4 86a55cb968d5 (public) "4: change a" files: a
| |
o | 3 0e6e235919dd (public) "3: copy a to e, change b" files: b e
| |
o | 2 0394b0d5e4f7 (public) "2: add dir/c" files: dir/c
|/
o 1 333546584845 (public) "1: add a and dir/b" files: a dir/b
|
o 0 d1a24e2ebd23 (public) "0: add 0" files: 0
$ cd ..
Convert excluding rev 0 and dir/ (and thus rev2):
$ cat << EOF > filemap
> exclude dir
> EOF
$ hg convert --filemap filemap source dest --config convert.hg.revs=1::
initializing destination dest repository
scanning source...
sorting...
converting...
5 1: add a and dir/b
4 2: add dir/c
3 3: copy a to e, change b
2 4: change a
1 5: merge 2 and 3, copy b to dir/d
0 6: change a
Verify that conversion skipped rev 2:
$ glog -R dest
o 4 78814e84a217 (draft) "6: change a" files: a
|
o 3 f7cff662c5e5 (draft) "5: merge 2 and 3, copy b to dir/d" files: e
|\
| o 2 ab40a95b0072 (draft) "4: change a" files: a
| |
o | 1 bd51f17597bf (draft) "3: copy a to e, change b" files: b e
|/
o 0 a4a1dae0fe35 (draft) "1: add a and dir/b" files: 0 a
Verify mapping correct in both directions:
$ cat source/.hg/shamap
a4a1dae0fe3514cefd9b8541b7abbc8f44f946d5 333546584845f70c4cfecb992341aaef0e708166
bd51f17597bf32268e68a560b206898c3960cda2 0e6e235919dd8e9285ba8eb5adf703af9ad99378
ab40a95b00725307e79c2fd271000aa8af9759f4 86a55cb968d51770cba2a1630d6cc637b574580a
f7cff662c5e581e6f3f1a85ffdd2bcb35825f6ba 717e9b37cdb7eb9917ca8e30aa3f986e6d5b177d
78814e84a217894517c2de392b903ed05e6871a4 0613c8e59a3ddb9789072ef52f1ed13496489bb4
$ cat dest/.hg/shamap
333546584845f70c4cfecb992341aaef0e708166 a4a1dae0fe3514cefd9b8541b7abbc8f44f946d5
0394b0d5e4f761ced559fd0bbdc6afc16cb3f7d1 a4a1dae0fe3514cefd9b8541b7abbc8f44f946d5
0e6e235919dd8e9285ba8eb5adf703af9ad99378 bd51f17597bf32268e68a560b206898c3960cda2
86a55cb968d51770cba2a1630d6cc637b574580a ab40a95b00725307e79c2fd271000aa8af9759f4
717e9b37cdb7eb9917ca8e30aa3f986e6d5b177d f7cff662c5e581e6f3f1a85ffdd2bcb35825f6ba
0613c8e59a3ddb9789072ef52f1ed13496489bb4 78814e84a217894517c2de392b903ed05e6871a4
Verify meta data converted correctly:
$ hg -R dest log -r 1 --debug -p --git
changeset: 1:bd51f17597bf32268e68a560b206898c3960cda2
phase: draft
parent: 0:a4a1dae0fe3514cefd9b8541b7abbc8f44f946d5
parent: -1:0000000000000000000000000000000000000000
manifest: 1:040c72ed9b101773c24ac314776bfc846943781f
user: test
date: Thu Jan 01 00:00:00 1970 +0000
files+: b e
extra: branch=default
description:
3: copy a to e, change b
diff --git a/b b/b
new file mode 100644
--- /dev/null
+++ b/b
@@ -0,0 +1,1 @@
+b
diff --git a/a b/e
copy from a
copy to e
Verify files included and excluded correctly:
$ hg -R dest manifest -r tip
0
a
b
e
Make changes in dest and convert back:
$ hg -R dest up -q
$ echo dest > dest/dest
$ hg -R dest ci -Aqm 'change in dest'
$ hg -R dest tip
changeset: 5:a2e0e3cc6d1d
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: change in dest
(converting merges back after using a filemap will probably cause chaos so we
exclude merges.)
$ hg convert dest source --config convert.hg.revs='!merge()'
scanning source...
sorting...
converting...
0 change in dest
Verify the conversion back:
$ hg -R source log --debug -r tip
changeset: 7:e6d364a69ff1248b2099e603b0c145504cade6f0
tag: tip
phase: draft
parent: 6:0613c8e59a3ddb9789072ef52f1ed13496489bb4
parent: -1:0000000000000000000000000000000000000000
manifest: 7:aa3e9542f3b76d4f1f1b2e9c7ce9dbb48b6a95ec
user: test
date: Thu Jan 01 00:00:00 1970 +0000
files+: dest
extra: branch=default
description:
change in dest
Files that had been excluded are still present:
$ hg -R source manifest -r tip
0
a
b
dest
dir/b
dir/c
dir/d
e
More source changes
$ cd source
$ echo 1 >> a
$ hg ci -m '8: source first branch'
created new head
$ hg up -qr -2
$ echo 2 >> a
$ hg ci -m '9: source second branch'
$ hg merge -q --tool internal:local
$ hg ci -m '10: source merge'
$ echo >> a
$ hg ci -m '11: source change'
$ hg mani
0
a
b
dest
dir/b
dir/c
dir/d
e
$ glog -r 6:
@ 11 0c8927d1f7f4 (draft) "11: source change" files: a
|
o 10 9ccb7ee8d261 (draft) "10: source merge" files: a
|\
| o 9 f131b1518dba (draft) "9: source second branch" files: a
| |
o | 8 669cf0e74b50 (draft) "8: source first branch" files: a
| |
| o 7 e6d364a69ff1 (draft) "change in dest" files: dest
|/
o 6 0613c8e59a3d (public) "6: change a" files: a
|
~
$ cd ..
$ hg convert --filemap filemap source dest --config convert.hg.revs=3:
scanning source...
sorting...
converting...
3 8: source first branch
2 9: source second branch
1 10: source merge
0 11: source change
$ glog -R dest
o 9 8432d597b263 (draft) "11: source change" files: a
|
o 8 632ffacdcd6f (draft) "10: source merge" files: a
|\
| o 7 049cfee90ee6 (draft) "9: source second branch" files: a
| |
o | 6 9b6845e036e5 (draft) "8: source first branch" files: a
| |
| @ 5 a2e0e3cc6d1d (draft) "change in dest" files: dest
|/
o 4 78814e84a217 (draft) "6: change a" files: a
|
o 3 f7cff662c5e5 (draft) "5: merge 2 and 3, copy b to dir/d" files: e
|\
| o 2 ab40a95b0072 (draft) "4: change a" files: a
| |
o | 1 bd51f17597bf (draft) "3: copy a to e, change b" files: b e
|/
o 0 a4a1dae0fe35 (draft) "1: add a and dir/b" files: 0 a
$ cd ..
Two way tests
$ hg init 0
$ echo f > 0/f
$ echo a > 0/a-only
$ echo b > 0/b-only
$ hg -R 0 ci -Aqm0
$ cat << EOF > filemap-a
> exclude b-only
> EOF
$ cat << EOF > filemap-b
> exclude a-only
> EOF
$ hg convert --filemap filemap-a 0 a
initializing destination a repository
scanning source...
sorting...
converting...
0 0
$ hg -R a up -q
$ echo a > a/f
$ hg -R a ci -ma
$ hg convert --filemap filemap-b 0 b
initializing destination b repository
scanning source...
sorting...
converting...
0 0
$ hg -R b up -q
$ echo b > b/f
$ hg -R b ci -mb
$ tail 0/.hg/shamap
86f3f774ffb682bffb5dc3c1d3b3da637cb9a0d6 8a028c7c77f6c7bd6d63bc3f02ca9f779eabf16a
dd9f218eb91fb857f2a62fe023e1d64a4e7812fe 8a028c7c77f6c7bd6d63bc3f02ca9f779eabf16a
$ tail a/.hg/shamap
8a028c7c77f6c7bd6d63bc3f02ca9f779eabf16a 86f3f774ffb682bffb5dc3c1d3b3da637cb9a0d6
$ tail b/.hg/shamap
8a028c7c77f6c7bd6d63bc3f02ca9f779eabf16a dd9f218eb91fb857f2a62fe023e1d64a4e7812fe
$ hg convert a 0
scanning source...
sorting...
converting...
0 a
$ hg convert b 0
scanning source...
sorting...
converting...
0 b
$ hg -R 0 log -G
o changeset: 2:637fbbbe96b6
| tag: tip
| parent: 0:8a028c7c77f6
| user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: b
|
| o changeset: 1:ec7b9c96e692
|/ user: test
| date: Thu Jan 01 00:00:00 1970 +0000
| summary: a
|
@ changeset: 0:8a028c7c77f6
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: 0
$ hg convert --filemap filemap-b 0 a --config convert.hg.revs=1::
scanning source...
sorting...
converting...
$ hg -R 0 up -r1
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo f >> 0/f
$ hg -R 0 ci -mx
$ hg convert --filemap filemap-b 0 a --config convert.hg.revs=1::
scanning source...
sorting...
converting...
0 x
$ hg -R a log -G -T '{rev} {desc|firstline} ({files})\n'
o 2 x (f)
|
@ 1 a (f)
|
o 0 0 (a-only f)
$ hg -R a mani -r tip
a-only
f
An additional round, demonstrating that unchanged files don't get converted
$ echo f >> 0/f
$ echo f >> 0/a-only
$ hg -R 0 ci -m "extra f+a-only change"
$ hg convert --filemap filemap-b 0 a --config convert.hg.revs=1::
scanning source...
sorting...
converting...
0 extra f+a-only change
$ hg -R a log -G -T '{rev} {desc|firstline} ({files})\n'
o 3 extra f+a-only change (f)
|
o 2 x (f)
|
@ 1 a (f)
|
o 0 0 (a-only f)
Conversion after rollback
$ hg -R a rollback -f
repository tip rolled back to revision 2 (undo convert)
$ hg convert --filemap filemap-b 0 a --config convert.hg.revs=1::
scanning source...
sorting...
converting...
0 extra f+a-only change
$ hg -R a log -G -T '{rev} {desc|firstline} ({files})\n'
o 3 extra f+a-only change (f)
|
o 2 x (f)
|
@ 1 a (f)
|
o 0 0 (a-only f)
Convert with --full adds and removes files that didn't change
$ echo f >> 0/f
$ hg -R 0 ci -m "f"
$ hg convert --filemap filemap-b --full 0 a --config convert.hg.revs=1::
scanning source...
sorting...
converting...
0 f
$ hg -R a status --change tip
M f
A b-only
R a-only
Recorded {files} list does not get confused about flags on merge commits
#if execbit
$ cd ..
$ hg init merge-flags-orig
$ cd merge-flags-orig
$ echo 0 > 0
$ hg ci -Aqm 'add 0'
$ echo a > a
$ chmod +x a
$ hg ci -qAm 'add executable file'
$ hg co -q 0
$ echo b > b
$ hg ci -qAm 'add file'
$ hg merge -q
$ hg ci -m 'merge'
$ hg log -G -T '{rev} {desc}\n'
@ 3 merge
|\
| o 2 add file
| |
o | 1 add executable file
|/
o 0 add 0
# No files changed
$ hg log -r 3 -T '{files}\n'
$ cd ..
$ hg convert merge-flags-orig merge-flags-new -q
$ cd merge-flags-new
$ hg log -G -T '{rev} {desc}\n'
o 3 merge
|\
| o 2 add file
| |
o | 1 add executable file
|/
o 0 add 0
# Still no files
$ hg log -r 3 -T '{files}\n'
#endif