Init repo1:

  $ hg init repo1

  $ cd repo1

  $ echo "some text" > a

  $ hg add

  adding a

  $ hg ci -m first

  $ cat .hg/store/fncache | sort

  data/a.i

Testing a.i/b:

  $ mkdir a.i

  $ echo "some other text" > a.i/b

  $ hg add

  adding a.i/b

  $ hg ci -m second

  $ cat .hg/store/fncache | sort

  data/a.i

  data/a.i.hg/b.i

Testing a.i.hg/c:

  $ mkdir a.i.hg

  $ echo "yet another text" > a.i.hg/c

  $ hg add

  adding a.i.hg/c

  $ hg ci -m third

  $ cat .hg/store/fncache | sort

  data/a.i

  data/a.i.hg.hg/c.i

  data/a.i.hg/b.i

Testing verify:

  $ hg verify

  checking changesets

  checking manifests

  crosschecking files in changesets and manifests

  checking files

  3 files, 3 changesets, 3 total revisions

  $ rm .hg/store/fncache

  $ hg verify

  checking changesets

  checking manifests

  crosschecking files in changesets and manifests

  checking files

   warning: revlog 'data/a.i' not in fncache!

   warning: revlog 'data/a.i.hg/c.i' not in fncache!

   warning: revlog 'data/a.i/b.i' not in fncache!

  3 files, 3 changesets, 3 total revisions

  3 warnings encountered!

  hint: run "hg debugrebuildfncache" to recover from corrupt fncache

Follow the hint to make sure it works

  $ hg debugrebuildfncache

  adding data/a.i

  adding data/a.i.hg/c.i

  adding data/a.i/b.i

  3 items added, 0 removed from fncache

  $ hg verify

  checking changesets

  checking manifests

  crosschecking files in changesets and manifests

  checking files

  3 files, 3 changesets, 3 total revisions

  $ cd ..

Non store repo:

  $ hg --config format.usestore=False init foo

  $ cd foo

  $ mkdir tst.d

  $ echo foo > tst.d/foo

  $ hg ci -Amfoo

  adding tst.d/foo

  $ find .hg | sort

  .hg

  .hg/00changelog.i

  .hg/00manifest.i

  .hg/cache

  .hg/cache/branch2-served

  .hg/cache/rbc-names-v1

  .hg/cache/rbc-revs-v1

  .hg/data

  .hg/data/tst.d.hg

  .hg/data/tst.d.hg/foo.i

  .hg/dirstate

  .hg/fsmonitor.state (fsmonitor !)

  .hg/last-message.txt

  .hg/phaseroots

  .hg/requires

  .hg/undo

  .hg/undo.backup.dirstate

  .hg/undo.backupfiles

  .hg/undo.bookmarks

  .hg/undo.branch

  .hg/undo.desc

  .hg/undo.dirstate

  .hg/undo.phaseroots

  $ cd ..

Non fncache repo:

  $ hg --config format.usefncache=False init bar

  $ cd bar

  $ mkdir tst.d

  $ echo foo > tst.d/Foo

  $ hg ci -Amfoo

  adding tst.d/Foo

  $ find .hg | sort

  .hg

  .hg/00changelog.i

  .hg/cache

  .hg/cache/branch2-served

  .hg/cache/rbc-names-v1

  .hg/cache/rbc-revs-v1

  .hg/dirstate

  .hg/fsmonitor.state (fsmonitor !)

  .hg/last-message.txt

  .hg/requires

  .hg/store

  .hg/store/00changelog.i

  .hg/store/00manifest.i

  .hg/store/data

  .hg/store/data/tst.d.hg

  .hg/store/data/tst.d.hg/_foo.i

  .hg/store/phaseroots

  .hg/store/undo

  .hg/store/undo.backupfiles

  .hg/store/undo.phaseroots

  .hg/undo.backup.dirstate

  .hg/undo.bookmarks

  .hg/undo.branch

  .hg/undo.desc

  .hg/undo.dirstate

  $ cd ..

Encoding of reserved / long paths in the store

  $ hg init r2

  $ cd r2

  $ cat <<EOF > .hg/hgrc

  > [ui]

  > portablefilenames = ignore

  > EOF

  $ hg import -q --bypass - <<EOF

  > # HG changeset patch

  > # User test

  > # Date 0 0

  > # Node ID 1c7a2f7cb77be1a0def34e4c7cabc562ad98fbd7

  > # Parent  0000000000000000000000000000000000000000

  > 1

  > 

  > diff --git a/12345678/12345678/12345678/12345678/12345678/12345678/12345678/12345/xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-123456789-12.3456789-12345-ABCDEFGHIJKLMNOPRSTUVWXYZ-abcdefghjiklmnopqrstuvwxyz b/12345678/12345678/12345678/12345678/12345678/12345678/12345678/12345/xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-123456789-12.3456789-12345-ABCDEFGHIJKLMNOPRSTUVWXYZ-abcdefghjiklmnopqrstuvwxyz

  > new file mode 100644

  > --- /dev/null

  > +++ b/12345678/12345678/12345678/12345678/12345678/12345678/12345678/12345/xxxxxxxxx-xxxxxxxxx-xxxxxxxxx-123456789-12.3456789-12345-ABCDEFGHIJKLMNOPRSTUVWXYZ-abcdefghjiklmnopqrstuvwxyz

  > @@ -0,0 +1,1 @@

  > +foo

  > diff --git a/AUX/SECOND/X.PRN/FOURTH/FI:FTH/SIXTH/SEVENTH/EIGHTH/NINETH/TENTH/ELEVENTH/LOREMIPSUM.TXT b/AUX/SECOND/X.PRN/FOURTH/FI:FTH/SIXTH/SEVENTH/EIGHTH/NINETH/TENTH/ELEVENTH/LOREMIPSUM.TXT

  > new file mode 100644

  > --- /dev/null

  > +++ b/AUX/SECOND/X.PRN/FOURTH/FI:FTH/SIXTH/SEVENTH/EIGHTH/NINETH/TENTH/ELEVENTH/LOREMIPSUM.TXT

  > @@ -0,0 +1,1 @@

  > +foo

  > diff --git a/Project Planning/Resources/AnotherLongDirectoryName/Followedbyanother/AndAnother/AndThenAnExtremelyLongFileName.txt b/Project Planning/Resources/AnotherLongDirectoryName/Followedbyanother/AndAnother/AndThenAnExtremelyLongFileName.txt

  > new file mode 100644

  > --- /dev/null

  > +++ b/Project Planning/Resources/AnotherLongDirectoryName/Followedbyanother/AndAnother/AndThenAnExtremelyLongFileName.txt	

  > @@ -0,0 +1,1 @@

  > +foo

  > diff --git a/bla.aux/prn/PRN/lpt/com3/nul/coma/foo.NUL/normal.c b/bla.aux/prn/PRN/lpt/com3/nul/coma/foo.NUL/normal.c

  > new file mode 100644

  > --- /dev/null

  > +++ b/bla.aux/prn/PRN/lpt/com3/nul/coma/foo.NUL/normal.c

  > @@ -0,0 +1,1 @@

  > +foo

  > diff --git a/enterprise/openesbaddons/contrib-imola/corba-bc/netbeansplugin/wsdlExtension/src/main/java/META-INF/services/org.netbeans.modules.xml.wsdl.bindingsupport.spi.ExtensibilityElementTemplateProvider b/enterprise/openesbaddons/contrib-imola/corba-bc/netbeansplugin/wsdlExtension/src/main/java/META-INF/services/org.netbeans.modules.xml.wsdl.bindingsupport.spi.ExtensibilityElementTemplateProvider

  > new file mode 100644

  > --- /dev/null

  > +++ b/enterprise/openesbaddons/contrib-imola/corba-bc/netbeansplugin/wsdlExtension/src/main/java/META-INF/services/org.netbeans.modules.xml.wsdl.bindingsupport.spi.ExtensibilityElementTemplateProvider

  > @@ -0,0 +1,1 @@

  > +foo

  > EOF

  $ find .hg/store -name *.i  | sort

  .hg/store/00changelog.i

  .hg/store/00manifest.i

  .hg/store/data/bla.aux/pr~6e/_p_r_n/lpt/co~6d3/nu~6c/coma/foo._n_u_l/normal.c.i

  .hg/store/dh/12345678/12345678/12345678/12345678/12345678/12345678/12345678/12345/xxxxxx168e07b38e65eff86ab579afaaa8e30bfbe0f35f.i

  .hg/store/dh/au~78/second/x.prn/fourth/fi~3afth/sixth/seventh/eighth/nineth/tenth/loremia20419e358ddff1bf8751e38288aff1d7c32ec05.i

  .hg/store/dh/enterpri/openesba/contrib-/corba-bc/netbeans/wsdlexte/src/main/java/org.net7018f27961fdf338a598a40c4683429e7ffb9743.i

  .hg/store/dh/project_/resource/anotherl/followed/andanoth/andthenanextremelylongfilename0d8e1f4187c650e2f1fdca9fd90f786bc0976b6b.i

  $ cd ..

Aborting lock does not prevent fncache writes

  $ cat > exceptionext.py <<EOF

  > from __future__ import absolute_import

  > import os

  > from mercurial import commands, error, extensions

  > 

  > def lockexception(orig, vfs, lockname, wait, releasefn, *args, **kwargs):

  >     def releasewrap():

  >         l.held = False # ensure __del__ is a noop

  >         raise error.Abort("forced lock failure")

  >     l = orig(vfs, lockname, wait, releasewrap, *args, **kwargs)

  >     return l

  > 

  > def reposetup(ui, repo):

  >     extensions.wrapfunction(repo, '_lock', lockexception)

  > 

  > cmdtable = {}

  > 

  > # wrap "commit" command to prevent wlock from being '__del__()'-ed

  > # at the end of dispatching (for intentional "forced lcok failure")

  > def commitwrap(orig, ui, repo, *pats, **opts):

  >     repo = repo.unfiltered() # to use replaced repo._lock certainly

  >     wlock = repo.wlock()

  >     try:

  >         return orig(ui, repo, *pats, **opts)

  >     finally:

  >         # multiple 'relase()' is needed for complete releasing wlock,

  >         # because "forced" abort at last releasing store lock

  >         # prevents wlock from being released at same 'lockmod.release()'

  >         for i in range(wlock.held):

  >             wlock.release()

  > 

  > def extsetup(ui):

  >     extensions.wrapcommand(commands.table, b"commit", commitwrap)

  > EOF

  $ extpath=`pwd`/exceptionext.py

  $ hg init fncachetxn

  $ cd fncachetxn

  $ printf "[extensions]\nexceptionext=$extpath\n" >> .hg/hgrc

  $ touch y

  $ hg ci -qAm y

  abort: forced lock failure

  [255]

  $ cat .hg/store/fncache

  data/y.i

Aborting transaction prevents fncache change

  $ cat > ../exceptionext.py <<EOF

  > from __future__ import absolute_import

  > import os

  > from mercurial import commands, error, extensions, localrepo

  > 

  > def wrapper(orig, self, *args, **kwargs):

  >     tr = orig(self, *args, **kwargs)

  >     def fail(tr):

  >         raise error.Abort(b"forced transaction failure")

  >     # zzz prefix to ensure it sorted after store.write

  >     tr.addfinalize(b'zzz-forcefails', fail)

  >     return tr

  > 

  > def uisetup(ui):

  >     extensions.wrapfunction(

  >         localrepo.localrepository, b'transaction', wrapper)

  > 

  > cmdtable = {}

  > 

  > EOF

Clean cached version

  $ rm -f "${extpath}c"

  $ rm -Rf "`dirname $extpath`/__pycache__"

  $ touch z

  $ hg ci -qAm z

  transaction abort!

  rollback completed

  abort: forced transaction failure

  [255]

  $ cat .hg/store/fncache

  data/y.i

Aborted transactions can be recovered later

  $ cat > ../exceptionext.py <<EOF

  > from __future__ import absolute_import

  > import os

  > from mercurial import (

  >   commands,

  >   error,

  >   extensions,

  >   localrepo,

  >   transaction,

  > )

  > 

  > def trwrapper(orig, self, *args, **kwargs):

  >     tr = orig(self, *args, **kwargs)

  >     def fail(tr):

  >         raise error.Abort("forced transaction failure")

  >     # zzz prefix to ensure it sorted after store.write

  >     tr.addfinalize('zzz-forcefails', fail)

  >     return tr

  > 

  > def abortwrapper(orig, self, *args, **kwargs):

  >     raise error.Abort("forced transaction failure")

  > 

  > def uisetup(ui):

  >     extensions.wrapfunction(localrepo.localrepository, 'transaction',

  >                             trwrapper)

  >     extensions.wrapfunction(transaction.transaction, '_abort',

  >                             abortwrapper)

  > 

  > cmdtable = {}

  > 

  > EOF

Clean cached versions

  $ rm -f "${extpath}c"

  $ rm -Rf "`dirname $extpath`/__pycache__"

  $ hg up -q 1

  $ touch z

  $ hg ci -qAm z 2>/dev/null

  [255]

  $ cat .hg/store/fncache | sort

  data/y.i

  data/z.i

  $ hg recover

  rolling back interrupted transaction

  checking changesets

  checking manifests