Mercurial > hg
view tests/test-merge-tools.t @ 26623:5a95fe44121d
clonebundles: support for seeding clones from pre-generated bundles
Cloning can be an expensive operation for servers because the server
generates a bundle from existing repository data at request time. For
a large repository like mozilla-central, this consumes 4+ minutes
of CPU time on the server. It also results in significant network
utilization. Multiplied by hundreds or even thousands of clients and
the ensuing load can result in difficulties scaling the Mercurial server.
Despite generation of bundles being deterministic until the next
changeset is added, the generation of bundles to service a clone request
is not cached. Each clone thus performs redundant work. This is
wasteful.
This patch introduces the "clonebundles" extension and related
client-side functionality to help alleviate this deficiency. The
client-side feature is behind an experimental flag and is not enabled by
default.
It works as follows:
1) Server operator generates a bundle and makes it available on a
server (likely HTTP).
2) Server operator defines the URL of a bundle file in a
.hg/clonebundles.manifest file.
3) Client `hg clone`ing sees the server is advertising bundle URLs.
4) Client fetches and applies the advertised bundle.
5) Client performs equivalent of `hg pull` to fetch changes made since
the bundle was created.
Essentially, the server performs the expensive work of generating a
bundle once and all subsequent clones fetch a static file from
somewhere. Scaling static file serving is a much more manageable
problem than scaling a Python application like Mercurial. Assuming your
repository grows less than 1% per day, the end result is 99+% of CPU
and network load from clones is eliminated, allowing Mercurial servers
to scale more easily. Serving static files also means data can be
transferred to clients as fast as they can consume it, rather than as
fast as servers can generate it. This makes clones faster.
Mozilla has implemented similar functionality of this patch on
hg.mozilla.org using a custom extension. We are hosting bundle files in
Amazon S3 and CloudFront (a CDN) and have successfully offloaded
>1 TB/day in data transfer from hg.mozilla.org, freeing up significant
bandwidth and CPU resources. The positive impact has been stellar and
I believe it has proved its value to be included in Mercurial core. I
feel it is important for the client-side support to be enabled in core
by default because it means that clients will get faster, more reliable
clones and will enable server operators to reduce load without
requiring any client-side configuration changes (assuming clients are
up to date, of course).
The scope of this feature is narrowly and specifically tailored to
cloning, despite "serve pulls from pre-generated bundles" being a valid
and useful feature. I would eventually like for Mercurial servers to
support transferring *all* repository data via statically hosted files.
You could imagine a server that siphons all pushed data to bundle files
and instructs clients to apply a stream of bundles to reconstruct all
repository data. This feature, while useful and powerful, is
significantly more work to implement because it requires the server
component have awareness of discovery and a mapping of which changesets
are in which files. Full, clone bundles, by contrast, are much simpler.
The wire protocol command is named "clonebundles" instead of something
more generic like "staticbundles" to leave the door open for a new, more
powerful and more generic server-side component with minimal backwards
compatibility implications. The name "bundleclone" is used by Mozilla's
extension and would cause problems since there are subtle differences
in Mozilla's extension.
Mozilla's experience with this idea has taught us that some form of
"content negotiation" is required. Not all clients will support all
bundle formats or even URLs (advanced TLS requirements, etc). To ensure
the highest uptake possible, a server needs to advertise multiple
versions of bundles and clients need to be able to choose the most
appropriate from that list one. The "attributes" in each
server-advertised entry facilitate this filtering and sorting. Their
use will become apparent in subsequent patches.
Initial inspiration and credit for the idea of cloning from static files
belongs to Augie Fackler and his "lookaside clone" extension proof of
concept.
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Fri, 09 Oct 2015 11:22:01 -0700 |
parents | ef1eb6df7071 |
children | a1e43e85d294 |
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test merge-tools configuration - mostly exercising filemerge.py $ unset HGMERGE # make sure HGMERGE doesn't interfere with the test $ hg init revision 0 $ echo "revision 0" > f $ echo "space" >> f $ hg commit -Am "revision 0" adding f revision 1 $ echo "revision 1" > f $ echo "space" >> f $ hg commit -Am "revision 1" $ hg update 0 > /dev/null revision 2 $ echo "revision 2" > f $ echo "space" >> f $ hg commit -Am "revision 2" created new head $ hg update 0 > /dev/null revision 3 - simple to merge $ echo "revision 3" >> f $ hg commit -Am "revision 3" created new head revision 4 - hard to merge $ hg update 0 > /dev/null $ echo "revision 4" > f $ hg commit -Am "revision 4" created new head $ echo "[merge-tools]" > .hg/hgrc $ beforemerge() { > cat .hg/hgrc > echo "# hg update -C 1" > hg update -C 1 > /dev/null > } $ aftermerge() { > echo "# cat f" > cat f > echo "# hg stat" > hg stat > rm -f f.orig > } Tool selection default is internal merge: $ beforemerge [merge-tools] # hg update -C 1 hg merge -r 2 override $PATH to ensure hgmerge not visible; use $PYTHON in case we're running from a devel copy, not a temp installation $ PATH="$BINDIR:/usr/sbin" $PYTHON "$BINDIR"/hg merge -r 2 merging f warning: conflicts while merging f! (edit, then use 'hg resolve --mark') 0 files updated, 0 files merged, 0 files removed, 1 files unresolved use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon [1] $ aftermerge # cat f <<<<<<< local: ef83787e2614 - test: revision 1 revision 1 ======= revision 2 >>>>>>> other: 0185f4e0cf02 - test: revision 2 space # hg stat M f ? f.orig simplest hgrc using false for merge: $ echo "false.whatever=" >> .hg/hgrc $ beforemerge [merge-tools] false.whatever= # hg update -C 1 $ hg merge -r 2 merging f merging f failed! 0 files updated, 0 files merged, 0 files removed, 1 files unresolved use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon [1] $ aftermerge # cat f revision 1 space # hg stat M f ? f.orig #if unix-permissions unexecutable file in $PATH shouldn't be found: $ echo "echo fail" > false $ hg up -qC 1 $ PATH="`pwd`:$BINDIR:/usr/sbin" $PYTHON "$BINDIR"/hg merge -r 2 merging f warning: conflicts while merging f! (edit, then use 'hg resolve --mark') 0 files updated, 0 files merged, 0 files removed, 1 files unresolved use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon [1] $ rm false #endif executable directory in $PATH shouldn't be found: $ mkdir false $ hg up -qC 1 $ PATH="`pwd`:$BINDIR:/usr/sbin" $PYTHON "$BINDIR"/hg merge -r 2 merging f warning: conflicts while merging f! (edit, then use 'hg resolve --mark') 0 files updated, 0 files merged, 0 files removed, 1 files unresolved use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon [1] $ rmdir false true with higher .priority gets precedence: $ echo "true.priority=1" >> .hg/hgrc $ beforemerge [merge-tools] false.whatever= true.priority=1 # hg update -C 1 $ hg merge -r 2 merging f 0 files updated, 1 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ aftermerge # cat f revision 1 space # hg stat M f unless lowered on command line: $ beforemerge [merge-tools] false.whatever= true.priority=1 # hg update -C 1 $ hg merge -r 2 --config merge-tools.true.priority=-7 merging f merging f failed! 0 files updated, 0 files merged, 0 files removed, 1 files unresolved use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon [1] $ aftermerge # cat f revision 1 space # hg stat M f ? f.orig or false set higher on command line: $ beforemerge [merge-tools] false.whatever= true.priority=1 # hg update -C 1 $ hg merge -r 2 --config merge-tools.false.priority=117 merging f merging f failed! 0 files updated, 0 files merged, 0 files removed, 1 files unresolved use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon [1] $ aftermerge # cat f revision 1 space # hg stat M f ? f.orig or true.executable not found in PATH: $ beforemerge [merge-tools] false.whatever= true.priority=1 # hg update -C 1 $ hg merge -r 2 --config merge-tools.true.executable=nonexistentmergetool merging f merging f failed! 0 files updated, 0 files merged, 0 files removed, 1 files unresolved use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon [1] $ aftermerge # cat f revision 1 space # hg stat M f ? f.orig or true.executable with bogus path: $ beforemerge [merge-tools] false.whatever= true.priority=1 # hg update -C 1 $ hg merge -r 2 --config merge-tools.true.executable=/nonexistent/mergetool merging f merging f failed! 0 files updated, 0 files merged, 0 files removed, 1 files unresolved use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon [1] $ aftermerge # cat f revision 1 space # hg stat M f ? f.orig but true.executable set to cat found in PATH works: $ echo "true.executable=cat" >> .hg/hgrc $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg merge -r 2 merging f revision 1 space revision 0 space revision 2 space 0 files updated, 1 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ aftermerge # cat f revision 1 space # hg stat M f and true.executable set to cat with path works: $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg merge -r 2 --config merge-tools.true.executable=cat merging f revision 1 space revision 0 space revision 2 space 0 files updated, 1 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ aftermerge # cat f revision 1 space # hg stat M f #if unix-permissions environment variables in true.executable are handled: $ echo 'echo "custom merge tool"' > .hg/merge.sh $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg --config merge-tools.true.executable='sh' \ > --config merge-tools.true.args=.hg/merge.sh \ > merge -r 2 merging f custom merge tool 0 files updated, 1 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ aftermerge # cat f revision 1 space # hg stat M f #endif Tool selection and merge-patterns merge-patterns specifies new tool false: $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg merge -r 2 --config merge-patterns.f=false merging f merging f failed! 0 files updated, 0 files merged, 0 files removed, 1 files unresolved use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon [1] $ aftermerge # cat f revision 1 space # hg stat M f ? f.orig merge-patterns specifies executable not found in PATH and gets warning: $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg merge -r 2 --config merge-patterns.f=true --config merge-tools.true.executable=nonexistentmergetool couldn't find merge tool true specified for f merging f couldn't find merge tool true specified for f merging f failed! 0 files updated, 0 files merged, 0 files removed, 1 files unresolved use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon [1] $ aftermerge # cat f revision 1 space # hg stat M f ? f.orig merge-patterns specifies executable with bogus path and gets warning: $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg merge -r 2 --config merge-patterns.f=true --config merge-tools.true.executable=/nonexistent/mergetool couldn't find merge tool true specified for f merging f couldn't find merge tool true specified for f merging f failed! 0 files updated, 0 files merged, 0 files removed, 1 files unresolved use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon [1] $ aftermerge # cat f revision 1 space # hg stat M f ? f.orig ui.merge overrules priority ui.merge specifies false: $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg merge -r 2 --config ui.merge=false merging f merging f failed! 0 files updated, 0 files merged, 0 files removed, 1 files unresolved use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon [1] $ aftermerge # cat f revision 1 space # hg stat M f ? f.orig ui.merge specifies internal:fail: $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg merge -r 2 --config ui.merge=internal:fail 0 files updated, 0 files merged, 0 files removed, 1 files unresolved use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon [1] $ aftermerge # cat f revision 1 space # hg stat M f ui.merge specifies :local (without internal prefix): $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg merge -r 2 --config ui.merge=:local 0 files updated, 1 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ aftermerge # cat f revision 1 space # hg stat M f ui.merge specifies internal:other: $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg merge -r 2 --config ui.merge=internal:other 0 files updated, 1 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ aftermerge # cat f revision 2 space # hg stat M f ui.merge specifies internal:prompt: $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg merge -r 2 --config ui.merge=internal:prompt no tool found to merge f keep (l)ocal or take (o)ther? l 0 files updated, 1 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ aftermerge # cat f revision 1 space # hg stat M f ui.merge specifies internal:dump: $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg merge -r 2 --config ui.merge=internal:dump merging f 0 files updated, 0 files merged, 0 files removed, 1 files unresolved use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon [1] $ aftermerge # cat f revision 1 space # hg stat M f ? f.base ? f.local ? f.orig ? f.other f.base: $ cat f.base revision 0 space f.local: $ cat f.local revision 1 space f.other: $ cat f.other revision 2 space $ rm f.base f.local f.other ui.merge specifies internal:other but is overruled by pattern for false: $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg merge -r 2 --config ui.merge=internal:other --config merge-patterns.f=false merging f merging f failed! 0 files updated, 0 files merged, 0 files removed, 1 files unresolved use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon [1] $ aftermerge # cat f revision 1 space # hg stat M f ? f.orig Premerge ui.merge specifies internal:other but is overruled by --tool=false $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg merge -r 2 --config ui.merge=internal:other --tool=false merging f merging f failed! 0 files updated, 0 files merged, 0 files removed, 1 files unresolved use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon [1] $ aftermerge # cat f revision 1 space # hg stat M f ? f.orig HGMERGE specifies internal:other but is overruled by --tool=false $ HGMERGE=internal:other ; export HGMERGE $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg merge -r 2 --tool=false merging f merging f failed! 0 files updated, 0 files merged, 0 files removed, 1 files unresolved use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon [1] $ aftermerge # cat f revision 1 space # hg stat M f ? f.orig $ unset HGMERGE # make sure HGMERGE doesn't interfere with remaining tests update is a merge ... (this also tests that files reverted with '--rev REV' are treated as "modified", even if none of mode, size and timestamp of them isn't changed on the filesystem (see also issue4583)) $ cat >> $HGRCPATH <<EOF > [fakedirstatewritetime] > # emulate invoking dirstate.write() via repo.status() > # at 2000-01-01 00:00 > fakenow = 200001010000 > EOF $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg update -q 0 $ f -s f f: size=17 $ touch -t 200001010000 f $ hg debugrebuildstate $ cat >> $HGRCPATH <<EOF > [extensions] > fakedirstatewritetime = $TESTDIR/fakedirstatewritetime.py > EOF $ hg revert -q -r 1 . $ cat >> $HGRCPATH <<EOF > [extensions] > fakedirstatewritetime = ! > EOF $ f -s f f: size=17 $ touch -t 200001010000 f $ hg status f M f $ hg update -r 2 merging f revision 1 space revision 0 space revision 2 space 0 files updated, 1 files merged, 0 files removed, 0 files unresolved $ aftermerge # cat f revision 1 space # hg stat M f update should also have --tool $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg update -q 0 $ f -s f f: size=17 $ touch -t 200001010000 f $ hg debugrebuildstate $ cat >> $HGRCPATH <<EOF > [extensions] > fakedirstatewritetime = $TESTDIR/fakedirstatewritetime.py > EOF $ hg revert -q -r 1 . $ cat >> $HGRCPATH <<EOF > [extensions] > fakedirstatewritetime = ! > EOF $ f -s f f: size=17 $ touch -t 200001010000 f $ hg status f M f $ hg update -r 2 --tool false merging f merging f failed! 0 files updated, 0 files merged, 0 files removed, 1 files unresolved use 'hg resolve' to retry unresolved file merges [1] $ aftermerge # cat f revision 1 space # hg stat M f ? f.orig Default is silent simplemerge: $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg merge -r 3 merging f 0 files updated, 1 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ aftermerge # cat f revision 1 space revision 3 # hg stat M f .premerge=True is same: $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg merge -r 3 --config merge-tools.true.premerge=True merging f 0 files updated, 1 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ aftermerge # cat f revision 1 space revision 3 # hg stat M f .premerge=False executes merge-tool: $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg merge -r 3 --config merge-tools.true.premerge=False merging f revision 1 space revision 0 space revision 0 space revision 3 0 files updated, 1 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ aftermerge # cat f revision 1 space # hg stat M f premerge=keep keeps conflict markers in: $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg merge -r 4 --config merge-tools.true.premerge=keep merging f <<<<<<< local: ef83787e2614 - test: revision 1 revision 1 space ======= revision 4 >>>>>>> other: 81448d39c9a0 - test: revision 4 revision 0 space revision 4 0 files updated, 1 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ aftermerge # cat f <<<<<<< local: ef83787e2614 - test: revision 1 revision 1 space ======= revision 4 >>>>>>> other: 81448d39c9a0 - test: revision 4 # hg stat M f premerge=keep-merge3 keeps conflict markers with base content: $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg merge -r 4 --config merge-tools.true.premerge=keep-merge3 merging f <<<<<<< local: ef83787e2614 - test: revision 1 revision 1 space ||||||| base revision 0 space ======= revision 4 >>>>>>> other: 81448d39c9a0 - test: revision 4 revision 0 space revision 4 0 files updated, 1 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ aftermerge # cat f <<<<<<< local: ef83787e2614 - test: revision 1 revision 1 space ||||||| base revision 0 space ======= revision 4 >>>>>>> other: 81448d39c9a0 - test: revision 4 # hg stat M f Tool execution set tools.args explicit to include $base $local $other $output: $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg merge -r 2 --config merge-tools.true.executable=head --config merge-tools.true.args='$base $local $other $output' \ > | sed 's,==> .* <==,==> ... <==,g' merging f ==> ... <== revision 0 space ==> ... <== revision 1 space ==> ... <== revision 2 space ==> ... <== revision 1 space 0 files updated, 1 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ aftermerge # cat f revision 1 space # hg stat M f Merge with "echo mergeresult > $local": $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg merge -r 2 --config merge-tools.true.executable=echo --config merge-tools.true.args='mergeresult > $local' merging f 0 files updated, 1 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ aftermerge # cat f mergeresult # hg stat M f - and $local is the file f: $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg merge -r 2 --config merge-tools.true.executable=echo --config merge-tools.true.args='mergeresult > f' merging f 0 files updated, 1 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ aftermerge # cat f mergeresult # hg stat M f Merge with "echo mergeresult > $output" - the variable is a bit magic: $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg merge -r 2 --config merge-tools.true.executable=echo --config merge-tools.true.args='mergeresult > $output' merging f 0 files updated, 1 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ aftermerge # cat f mergeresult # hg stat M f Merge using tool with a path that must be quoted: $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ cat <<EOF > 'my merge tool' > cat "\$1" "\$2" "\$3" > "\$4" > EOF $ hg --config merge-tools.true.executable='sh' \ > --config merge-tools.true.args='"./my merge tool" $base $local $other $output' \ > merge -r 2 merging f 0 files updated, 1 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ rm -f 'my merge tool' $ aftermerge # cat f revision 0 space revision 1 space revision 2 space # hg stat M f Issue3581: Merging a filename that needs to be quoted (This test doesn't work on Windows filesystems even on Linux, so check for Unix-like permission) #if unix-permissions $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ echo "revision 5" > '"; exit 1; echo "' $ hg commit -Am "revision 5" adding "; exit 1; echo " warning: filename contains '"', which is reserved on Windows: '"; exit 1; echo "' $ hg update -C 1 > /dev/null $ echo "revision 6" > '"; exit 1; echo "' $ hg commit -Am "revision 6" adding "; exit 1; echo " warning: filename contains '"', which is reserved on Windows: '"; exit 1; echo "' created new head $ hg merge --config merge-tools.true.executable="true" -r 5 merging "; exit 1; echo " 0 files updated, 1 files merged, 0 files removed, 0 files unresolved (branch merge, don't forget to commit) $ hg update -C 1 > /dev/null #endif Merge post-processing cat is a bad merge-tool and doesn't change: $ beforemerge [merge-tools] false.whatever= true.priority=1 true.executable=cat # hg update -C 1 $ hg merge -y -r 2 --config merge-tools.true.checkchanged=1 merging f revision 1 space revision 0 space revision 2 space output file f appears unchanged was merge successful (yn)? n merging f failed! 0 files updated, 0 files merged, 0 files removed, 1 files unresolved use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon [1] $ aftermerge # cat f revision 1 space # hg stat M f ? f.orig #if symlink internal merge cannot handle symlinks and shouldn't try: $ hg update -q -C 1 $ rm f $ ln -s symlink f $ hg commit -qm 'f is symlink' $ hg merge -r 2 --tool internal:merge merging f warning: internal :merge cannot merge symlinks for f warning: conflicts while merging f! (edit, then use 'hg resolve --mark') 0 files updated, 0 files merged, 0 files removed, 1 files unresolved use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon [1] #endif