fileset: add a lightweight file filtering language
This patch was inspired by one that Jun Wu authored for the fb-experimental
repo, to avoid using matcher for efficiency[1]. We want a way to specify what
files will be converted to LFS at commit time. And per discussion, we also want
to specify what files to skip, text diff, or merge in another config option.
The current `lfs.threshold` config option could not satisfy complex needs. I'm
putting it in a core package because Augie floated the idea of also using it for
narrow and sparse.
Yuya suggested farming out to fileset.parse(), which added support for more
symbols. The only fileset element not supported here is 'negate'. (List isn't
supported by filesets either.) I also changed the 'always' token to the 'all()'
predicate for consistency, and introduced 'none()' to improve readability in a
future tracked file based config. The extension operator was changed from '.'
to '**', to match how recursive path globs are specified. Finally, I changed
the path matcher from '/' to 'path:' at Yuya's suggestion, for consistency with
matcher. Unfortunately, ':' is currently reserved in filesets, so this has to
be quoted to be processed as a string instead of a symbol[2]. We should
probably revisit that, because it's seriously ugly. But it's only used by an
experimental extension, and I think using a file based config for LFS may drive
some more tweaks, so I'm settling for this for now.
I reserved all of the glob characters in fileset except '.' and '_' for the
extension test because those are likely valid extension characters.
Sample filter settings:
all() # everything
size(">20MB") # larger than 20MB
!**.txt # except for .txt files
**.zip | **.tar.gz | **.7z # some types of compressed files
"path:bin" # files under "bin" in the project root
[1] https://www.mercurial-scm.org/pipermail/mercurial-devel/2017-December/109387.html
[2] https://www.mercurial-scm.org/pipermail/mercurial-devel/2018-January/109729.html
$ hg init repo
$ cd repo
$ echo a > a
$ hg add a
$ hg commit -m test
Do we ever miss a sub-second change?:
$ for i in 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20; do
> hg co -qC 0
> echo b > a
> hg st
> done
M a
M a
M a
M a
M a
M a
M a
M a
M a
M a
M a
M a
M a
M a
M a
M a
M a
M a
M a
M a
$ echo test > b
$ mkdir dir1
$ echo test > dir1/c
$ echo test > d
$ echo test > e
#if execbit
A directory will typically have the execute bit -- make sure it doesn't get
confused with a file with the exec bit set
$ chmod +x e
#endif
$ hg add b dir1 d e
adding dir1/c
$ hg commit -m test2
$ cat >> $TESTTMP/dirstaterace.py << EOF
> from mercurial import (
> context,
> extensions,
> )
> def extsetup():
> extensions.wrapfunction(context.workingctx, '_checklookup', overridechecklookup)
> def overridechecklookup(orig, self, files):
> # make an update that changes the dirstate from underneath
> self._repo.ui.system(r"sh '$TESTTMP/dirstaterace.sh'",
> cwd=self._repo.root)
> return orig(self, files)
> EOF
$ hg debugrebuilddirstate
$ hg debugdirstate
n 0 -1 unset a
n 0 -1 unset b
n 0 -1 unset d
n 0 -1 unset dir1/c
n 0 -1 unset e
XXX Note that this returns M for files that got replaced by directories. This is
definitely a bug, but the fix for that is hard and the next status run is fine
anyway.
$ cat > $TESTTMP/dirstaterace.sh <<EOF
> rm b && rm -r dir1 && rm d && mkdir d && rm e && mkdir e
> EOF
$ hg status --config extensions.dirstaterace=$TESTTMP/dirstaterace.py
M d
M e
! b
! dir1/c
$ hg debugdirstate
n 644 2 * a (glob)
n 0 -1 unset b
n 0 -1 unset d
n 0 -1 unset dir1/c
n 0 -1 unset e
$ hg status
! b
! d
! dir1/c
! e
$ rmdir d e
$ hg update -C -q .
Test that dirstate changes aren't written out at the end of "hg
status", if .hg/dirstate is already changed simultaneously before
acquisition of wlock in workingctx._poststatusfixup().
This avoidance is important to keep consistency of dirstate in race
condition (see issue5584 for detail).
$ hg parents -q
1:* (glob)
$ hg debugrebuilddirstate
$ hg debugdirstate
n 0 -1 unset a
n 0 -1 unset b
n 0 -1 unset d
n 0 -1 unset dir1/c
n 0 -1 unset e
$ cat > $TESTTMP/dirstaterace.sh <<EOF
> # This script assumes timetable of typical issue5584 case below:
> #
> # 1. "hg status" loads .hg/dirstate
> # 2. "hg status" confirms clean-ness of FILE
> # 3. "hg update -C 0" updates the working directory simultaneously
> # (FILE is removed, and FILE is dropped from .hg/dirstate)
> # 4. "hg status" acquires wlock
> # (.hg/dirstate is re-loaded = no FILE entry in dirstate)
> # 5. "hg status" marks FILE in dirstate as clean
> # (FILE entry is added to in-memory dirstate)
> # 6. "hg status" writes dirstate changes into .hg/dirstate
> # (FILE entry is written into .hg/dirstate)
> #
> # To reproduce similar situation easily and certainly, #2 and #3
> # are swapped. "hg cat" below ensures #2 on "hg status" side.
>
> hg update -q -C 0
> hg cat -r 1 b > b
> EOF
"hg status" below should excludes "e", of which exec flag is set, for
portability of test scenario, because unsure but missing "e" is
treated differently in _checklookup() according to runtime platform.
- "missing(!)" on POSIX, "pctx[f].cmp(self[f])" raises ENOENT
- "modified(M)" on Windows, "self.flags(f) != pctx.flags(f)" is True
$ hg status --config extensions.dirstaterace=$TESTTMP/dirstaterace.py --debug -X path:e
skip updating dirstate: identity mismatch
M a
! d
! dir1/c
$ hg parents -q
0:* (glob)
$ hg files
a
$ hg debugdirstate
n * * * a (glob)
$ rm b
#if fsmonitor
Create fsmonitor state.
$ hg status
$ f --type .hg/fsmonitor.state
.hg/fsmonitor.state: file
Test that invalidating fsmonitor state in the middle (which doesn't require the
wlock) causes the fsmonitor update to be skipped.
hg debugrebuilddirstate ensures that the dirstaterace hook will be called, but
it also invalidates the fsmonitor state. So back it up and restore it.
$ mv .hg/fsmonitor.state .hg/fsmonitor.state.tmp
$ hg debugrebuilddirstate
$ mv .hg/fsmonitor.state.tmp .hg/fsmonitor.state
$ cat > $TESTTMP/dirstaterace.sh <<EOF
> rm .hg/fsmonitor.state
> EOF
$ hg status --config extensions.dirstaterace=$TESTTMP/dirstaterace.py --debug
skip updating fsmonitor.state: identity mismatch
$ f .hg/fsmonitor.state
.hg/fsmonitor.state: file not found
#endif
Set up a rebase situation for issue5581.
$ echo c2 > a
$ echo c2 > b
$ hg add b
$ hg commit -m c2
created new head
$ echo c3 >> a
$ hg commit -m c3
$ hg update 2
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo c4 >> a
$ echo c4 >> b
$ hg commit -m c4
created new head
Configure a merge tool that runs status in the middle of the rebase. The goal of
the status call is to trigger a potential bug if fsmonitor's state is written
even though the wlock is held by another process. The output of 'hg status' in
the merge tool goes to /dev/null because we're more interested in the results of
'hg status' run after the rebase.
$ cat >> $TESTTMP/mergetool-race.sh << EOF
> echo "custom merge tool"
> printf "c2\nc3\nc4\n" > \$1
> hg --cwd "$TESTTMP/repo" status > /dev/null
> echo "custom merge tool end"
> EOF
$ cat >> $HGRCPATH << EOF
> [extensions]
> rebase =
> [merge-tools]
> test.executable=sh
> test.args=$TESTTMP/mergetool-race.sh \$output
> EOF
$ hg rebase -s . -d 3 --tool test
rebasing 4:b08445fd6b2a "c4" (tip)
merging a
custom merge tool
custom merge tool end
saved backup bundle to $TESTTMP/repo/.hg/strip-backup/* (glob)
This hg status should be empty, whether or not fsmonitor is enabled (issue5581).
$ hg status