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
#require no-windows
$ . "$TESTDIR/remotefilelog-library.sh"
$ cat >> $HGRCPATH <<EOF
> [remotefilelog]
> fastdatapack=True
> [devel]
> remotefilelog.bg-wait=True
> EOF
$ hg init master
$ cd master
$ cat >> .hg/hgrc <<EOF
> [remotefilelog]
> server=True
> serverexpiration=-1
> EOF
$ echo x > x
$ hg commit -qAm x
$ echo x >> x
$ hg commit -qAm x2
$ cd ..
$ hgcloneshallow ssh://user@dummy/master shallow -q
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over *s (glob)
# Set the prefetchdays config to zero so that all commits are prefetched
# no matter what their creation date is.
$ cd shallow
$ cat >> .hg/hgrc <<EOF
> [remotefilelog]
> prefetchdays=0
> EOF
$ cd ..
# Test that repack cleans up the old files and creates new packs
$ cd shallow
$ find $CACHEDIR | sort
$TESTTMP/hgcache
$TESTTMP/hgcache/master
$TESTTMP/hgcache/master/11
$TESTTMP/hgcache/master/11/f6ad8ec52a2984abaafd7c3b516503785c2072
$TESTTMP/hgcache/master/11/f6ad8ec52a2984abaafd7c3b516503785c2072/aee31534993a501858fb6dd96a065671922e7d51
$TESTTMP/hgcache/repos
$ hg repack
$ find $CACHEDIR | sort
$TESTTMP/hgcache
$TESTTMP/hgcache/master
$TESTTMP/hgcache/master/packs
$TESTTMP/hgcache/master/packs/1e91b207daf5d7b48f1be9c587d6b5ae654ce78c.histidx
$TESTTMP/hgcache/master/packs/1e91b207daf5d7b48f1be9c587d6b5ae654ce78c.histpack
$TESTTMP/hgcache/master/packs/b1e0cfc7f345e408a7825e3081501959488d59ce.dataidx
$TESTTMP/hgcache/master/packs/b1e0cfc7f345e408a7825e3081501959488d59ce.datapack
$TESTTMP/hgcache/repos
# Test that the packs are readonly
$ ls_l $CACHEDIR/master/packs
-r--r--r-- 1145 1e91b207daf5d7b48f1be9c587d6b5ae654ce78c.histidx
-r--r--r-- 172 1e91b207daf5d7b48f1be9c587d6b5ae654ce78c.histpack
-r--r--r-- 1074 b1e0cfc7f345e408a7825e3081501959488d59ce.dataidx
-r--r--r-- 72 b1e0cfc7f345e408a7825e3081501959488d59ce.datapack
# Test that the data in the new packs is accessible
$ hg cat -r . x
x
x
# Test that adding new data and repacking it results in the loose data and the
# old packs being combined.
$ cd ../master
$ echo x >> x
$ hg commit -m x3
$ cd ../shallow
$ hg pull -q
$ hg up -q tip
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over * (glob)
$ find $CACHEDIR -type f | sort
$TESTTMP/hgcache/master/11/f6ad8ec52a2984abaafd7c3b516503785c2072/d4a3ed9310e5bd9887e3bf779da5077efab28216
$TESTTMP/hgcache/master/packs/1e91b207daf5d7b48f1be9c587d6b5ae654ce78c.histidx
$TESTTMP/hgcache/master/packs/1e91b207daf5d7b48f1be9c587d6b5ae654ce78c.histpack
$TESTTMP/hgcache/master/packs/b1e0cfc7f345e408a7825e3081501959488d59ce.dataidx
$TESTTMP/hgcache/master/packs/b1e0cfc7f345e408a7825e3081501959488d59ce.datapack
$TESTTMP/hgcache/repos
$ hg repack --traceback
$ find $CACHEDIR -type f | sort
$TESTTMP/hgcache/master/packs/78840d69389c7404327f7477e3931c89945c37d1.dataidx
$TESTTMP/hgcache/master/packs/78840d69389c7404327f7477e3931c89945c37d1.datapack
$TESTTMP/hgcache/master/packs/8abe7889aae389337d12ebe6085d4ee13854c7c9.histidx
$TESTTMP/hgcache/master/packs/8abe7889aae389337d12ebe6085d4ee13854c7c9.histpack
$TESTTMP/hgcache/repos
# Verify all the file data is still available
$ hg cat -r . x
x
x
x
$ hg cat -r '.^' x
x
x
# Test that repacking again without new data does not delete the pack files
# and did not change the pack names
$ hg repack
$ find $CACHEDIR -type f | sort
$TESTTMP/hgcache/master/packs/78840d69389c7404327f7477e3931c89945c37d1.dataidx
$TESTTMP/hgcache/master/packs/78840d69389c7404327f7477e3931c89945c37d1.datapack
$TESTTMP/hgcache/master/packs/8abe7889aae389337d12ebe6085d4ee13854c7c9.histidx
$TESTTMP/hgcache/master/packs/8abe7889aae389337d12ebe6085d4ee13854c7c9.histpack
$TESTTMP/hgcache/repos
# Run two repacks at once
$ hg repack --config "hooks.prerepack=sleep 3" &
$ sleep 1
$ hg repack
skipping repack - another repack is already running
$ hg debugwaitonrepack >/dev/null 2>&1
# Run repack in the background
$ cd ../master
$ echo x >> x
$ hg commit -m x4
$ cd ../shallow
$ hg pull -q
$ hg up -q tip
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over * (glob)
$ find $CACHEDIR -type f | sort
$TESTTMP/hgcache/master/11/f6ad8ec52a2984abaafd7c3b516503785c2072/1bb2e6237e035c8f8ef508e281f1ce075bc6db72
$TESTTMP/hgcache/master/packs/78840d69389c7404327f7477e3931c89945c37d1.dataidx
$TESTTMP/hgcache/master/packs/78840d69389c7404327f7477e3931c89945c37d1.datapack
$TESTTMP/hgcache/master/packs/8abe7889aae389337d12ebe6085d4ee13854c7c9.histidx
$TESTTMP/hgcache/master/packs/8abe7889aae389337d12ebe6085d4ee13854c7c9.histpack
$TESTTMP/hgcache/repos
$ hg repack --background
(running background repack)
$ find $CACHEDIR -type f | sort
$TESTTMP/hgcache/master/packs/39443fa1064182e93d968b5cba292eb5283260d0.dataidx
$TESTTMP/hgcache/master/packs/39443fa1064182e93d968b5cba292eb5283260d0.datapack
$TESTTMP/hgcache/master/packs/604552d403a1381749faf656feca0ca265a6d52c.histidx
$TESTTMP/hgcache/master/packs/604552d403a1381749faf656feca0ca265a6d52c.histpack
$TESTTMP/hgcache/repos
# Test debug commands
$ hg debugdatapack $TESTTMP/hgcache/master/packs/*.datapack
$TESTTMP/hgcache/master/packs/39443fa1064182e93d968b5cba292eb5283260d0:
x:
Node Delta Base Delta Length Blob Size
1bb2e6237e03 000000000000 8 8
d4a3ed9310e5 1bb2e6237e03 12 6
aee31534993a d4a3ed9310e5 12 4
Total: 32 18 (77.8% bigger)
$ hg debugdatapack --long $TESTTMP/hgcache/master/packs/*.datapack
$TESTTMP/hgcache/master/packs/39443fa1064182e93d968b5cba292eb5283260d0:
x:
Node Delta Base Delta Length Blob Size
1bb2e6237e035c8f8ef508e281f1ce075bc6db72 0000000000000000000000000000000000000000 8 8
d4a3ed9310e5bd9887e3bf779da5077efab28216 1bb2e6237e035c8f8ef508e281f1ce075bc6db72 12 6
aee31534993a501858fb6dd96a065671922e7d51 d4a3ed9310e5bd9887e3bf779da5077efab28216 12 4
Total: 32 18 (77.8% bigger)
$ hg debugdatapack $TESTTMP/hgcache/master/packs/*.datapack --node d4a3ed9310e5bd9887e3bf779da5077efab28216
$TESTTMP/hgcache/master/packs/39443fa1064182e93d968b5cba292eb5283260d0:
x
Node Delta Base Delta SHA1 Delta Length
d4a3ed9310e5bd9887e3bf779da5077efab28216 1bb2e6237e035c8f8ef508e281f1ce075bc6db72 77029ab56e83ea2115dd53ff87483682abe5d7ca 12
Node Delta Base Delta SHA1 Delta Length
1bb2e6237e035c8f8ef508e281f1ce075bc6db72 0000000000000000000000000000000000000000 7ca8c71a64f7b56380e77573da2f7a5fdd2ecdb5 8
$ hg debughistorypack $TESTTMP/hgcache/master/packs/*.histidx
x
Node P1 Node P2 Node Link Node Copy From
1bb2e6237e03 d4a3ed9310e5 000000000000 0b03bbc9e1e7
d4a3ed9310e5 aee31534993a 000000000000 421535db10b6
aee31534993a 1406e7411862 000000000000 a89d614e2364
1406e7411862 000000000000 000000000000 b292c1e3311f
# Test copy tracing from a pack
$ cd ../master
$ hg mv x y
$ hg commit -m 'move x to y'
$ cd ../shallow
$ hg pull -q
$ hg up -q tip
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over * (glob)
$ hg repack
$ hg log -f y -T '{desc}\n'
move x to y
x4
x3
x2
x
# Test copy trace across rename and back
$ cp -R $TESTTMP/hgcache/master/packs $TESTTMP/backuppacks
$ cd ../master
$ hg mv y x
$ hg commit -m 'move y back to x'
$ hg revert -r 0 x
$ mv x y
$ hg add y
$ echo >> y
$ hg revert x
$ hg commit -m 'add y back without metadata'
$ cd ../shallow
$ hg pull -q
$ hg up -q tip
2 files fetched over 2 fetches - (2 misses, 0.00% hit ratio) over * (glob)
$ hg repack
$ ls $TESTTMP/hgcache/master/packs
bfd60adb76018bb952e27cd23fc151bf94865d7d.histidx
bfd60adb76018bb952e27cd23fc151bf94865d7d.histpack
fb3aa57b22789ebcc45706c352e2d6af099c5816.dataidx
fb3aa57b22789ebcc45706c352e2d6af099c5816.datapack
$ hg debughistorypack $TESTTMP/hgcache/master/packs/*.histidx
x
Node P1 Node P2 Node Link Node Copy From
cd410a44d584 577959738234 000000000000 609547eda446 y
1bb2e6237e03 d4a3ed9310e5 000000000000 0b03bbc9e1e7
d4a3ed9310e5 aee31534993a 000000000000 421535db10b6
aee31534993a 1406e7411862 000000000000 a89d614e2364
1406e7411862 000000000000 000000000000 b292c1e3311f
y
Node P1 Node P2 Node Link Node Copy From
577959738234 1bb2e6237e03 000000000000 c7faf2fc439a x
21f46f2721e7 000000000000 000000000000 d6868642b790
$ hg strip -r '.^'
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
saved backup bundle to $TESTTMP/shallow/.hg/strip-backup/609547eda446-b26b56a8-backup.hg (glob)
$ hg -R ../master strip -r '.^'
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
saved backup bundle to $TESTTMP/master/.hg/strip-backup/609547eda446-b26b56a8-backup.hg (glob)
$ rm -rf $TESTTMP/hgcache/master/packs
$ cp -R $TESTTMP/backuppacks $TESTTMP/hgcache/master/packs
# Test repacking datapack without history
$ rm -rf $CACHEDIR/master/packs/*hist*
$ hg repack
$ hg debugdatapack $TESTTMP/hgcache/master/packs/*.datapack
$TESTTMP/hgcache/master/packs/922aca43dbbeda4d250565372e8892ec7b08da6a:
x:
Node Delta Base Delta Length Blob Size
1bb2e6237e03 000000000000 8 8
d4a3ed9310e5 1bb2e6237e03 12 6
aee31534993a d4a3ed9310e5 12 4
Total: 32 18 (77.8% bigger)
y:
Node Delta Base Delta Length Blob Size
577959738234 000000000000 70 8
Total: 70 8 (775.0% bigger)
$ hg cat -r ".^" x
x
x
x
x
Incremental repack
$ rm -rf $CACHEDIR/master/packs/*
$ cat >> .hg/hgrc <<EOF
> [remotefilelog]
> data.generations=60
> 150
> EOF
Single pack - repack does nothing
$ hg prefetch -r 0
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over * (glob)
$ ls_l $TESTTMP/hgcache/master/packs/ | grep datapack
[1]
$ ls_l $TESTTMP/hgcache/master/packs/ | grep histpack
[1]
$ hg repack --incremental
$ ls_l $TESTTMP/hgcache/master/packs/ | grep datapack
-r--r--r-- 70 052643fdcdebbd42d7c180a651a30d46098e6fe1.datapack
$ ls_l $TESTTMP/hgcache/master/packs/ | grep histpack
-r--r--r-- 90 955a622173324b2d8b53e1147f209f1cf125302e.histpack
3 gen1 packs, 1 gen0 pack - packs 3 gen1 into 1
$ hg prefetch -r 1
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over * (glob)
$ hg prefetch -r 2
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over * (glob)
$ hg prefetch -r 3
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over * (glob)
$ ls_l $TESTTMP/hgcache/master/packs/ | grep datapack
-r--r--r-- 70 052643fdcdebbd42d7c180a651a30d46098e6fe1.datapack
$ ls_l $TESTTMP/hgcache/master/packs/ | grep histpack
-r--r--r-- 90 955a622173324b2d8b53e1147f209f1cf125302e.histpack
$ hg repack --incremental
$ ls_l $TESTTMP/hgcache/master/packs/ | grep datapack
-r--r--r-- 70 052643fdcdebbd42d7c180a651a30d46098e6fe1.datapack
-r--r--r-- 226 39443fa1064182e93d968b5cba292eb5283260d0.datapack
$ ls_l $TESTTMP/hgcache/master/packs/ | grep histpack
-r--r--r-- 336 604552d403a1381749faf656feca0ca265a6d52c.histpack
-r--r--r-- 90 955a622173324b2d8b53e1147f209f1cf125302e.histpack
1 gen3 pack, 1 gen0 pack - does nothing
$ hg repack --incremental
$ ls_l $TESTTMP/hgcache/master/packs/ | grep datapack
-r--r--r-- 70 052643fdcdebbd42d7c180a651a30d46098e6fe1.datapack
-r--r--r-- 226 39443fa1064182e93d968b5cba292eb5283260d0.datapack
$ ls_l $TESTTMP/hgcache/master/packs/ | grep histpack
-r--r--r-- 336 604552d403a1381749faf656feca0ca265a6d52c.histpack
-r--r--r-- 90 955a622173324b2d8b53e1147f209f1cf125302e.histpack
Pull should run background repack
$ cat >> .hg/hgrc <<EOF
> [remotefilelog]
> backgroundrepack=True
> EOF
$ clearcache
$ hg prefetch -r 0
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over * (glob)
$ hg prefetch -r 1
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over * (glob)
$ hg prefetch -r 2
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over * (glob)
$ hg prefetch -r 3
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over * (glob)
$ hg pull
pulling from ssh://user@dummy/master
searching for changes
no changes found
(running background incremental repack)
$ ls_l $TESTTMP/hgcache/master/packs/ | grep datapack
-r--r--r-- 303 156a6c1c83aeb69422d7936e0a46ba9bc06a71c0.datapack
$ ls_l $TESTTMP/hgcache/master/packs/ | grep histpack
-r--r--r-- 336 604552d403a1381749faf656feca0ca265a6d52c.histpack
Test environment variable resolution
$ CACHEPATH=$TESTTMP/envcache hg prefetch --config 'remotefilelog.cachepath=$CACHEPATH'
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over * (glob)
$ find $TESTTMP/envcache | sort
$TESTTMP/envcache
$TESTTMP/envcache/master
$TESTTMP/envcache/master/95
$TESTTMP/envcache/master/95/cb0bfd2977c761298d9624e4b4d4c72a39974a
$TESTTMP/envcache/master/95/cb0bfd2977c761298d9624e4b4d4c72a39974a/577959738234a1eb241ed3ed4b22a575833f56e0
$TESTTMP/envcache/repos
Test local remotefilelog blob is correct when based on a pack
$ hg prefetch -r .
1 files fetched over 1 fetches - (1 misses, 0.00% hit ratio) over * (glob)
$ echo >> y
$ hg commit -m y2
$ hg debugremotefilelog .hg/store/data/95cb0bfd2977c761298d9624e4b4d4c72a39974a/b70860edba4f8242a1d52f2a94679dd23cb76808
size: 9 bytes
path: .hg/store/data/95cb0bfd2977c761298d9624e4b4d4c72a39974a/b70860edba4f8242a1d52f2a94679dd23cb76808
key: b70860edba4f
node => p1 p2 linknode copyfrom
b70860edba4f => 577959738234 000000000000 08d3fbc98c48
577959738234 => 1bb2e6237e03 000000000000 c7faf2fc439a x
1bb2e6237e03 => d4a3ed9310e5 000000000000 0b03bbc9e1e7
d4a3ed9310e5 => aee31534993a 000000000000 421535db10b6
aee31534993a => 1406e7411862 000000000000 a89d614e2364
1406e7411862 => 000000000000 000000000000 b292c1e3311f