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
$ echo foo > bar
$ hg commit -Am default
adding bar
$ hg up -r null
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ hg branch mine
marked working directory as branch mine
(branches are permanent and global, did you want a bookmark?)
$ echo hello > world
$ hg commit -Am hello
adding world
$ hg up -r null
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ hg branch other
marked working directory as branch other
$ echo good > bye
$ hg commit -Am other
adding bye
$ hg up -r mine
1 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ hg clone -U -u . .#other ../b -r 0 -r 1 -r 2 -b other
abort: cannot specify both --noupdate and --updaterev
[255]
$ hg clone -U .#other ../b -r 0 -r 1 -r 2 -b other
adding changesets
adding manifests
adding file changes
added 3 changesets with 3 changes to 3 files (+2 heads)
new changesets 8c68ee086fd0:fcc393352796
$ rm -rf ../b
$ hg clone -u . .#other ../b -r 0 -r 1 -r 2 -b other
adding changesets
adding manifests
adding file changes
added 3 changesets with 3 changes to 3 files (+2 heads)
new changesets 8c68ee086fd0:fcc393352796
updating to branch mine
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf ../b
$ hg clone -u 0 .#other ../b -r 0 -r 1 -r 2 -b other
adding changesets
adding manifests
adding file changes
added 3 changesets with 3 changes to 3 files (+2 heads)
new changesets 8c68ee086fd0:fcc393352796
updating to branch default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf ../b
$ hg clone -u 1 .#other ../b -r 0 -r 1 -r 2 -b other
adding changesets
adding manifests
adding file changes
added 3 changesets with 3 changes to 3 files (+2 heads)
new changesets 8c68ee086fd0:fcc393352796
updating to branch mine
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf ../b
$ hg clone -u 2 .#other ../b -r 0 -r 1 -r 2 -b other
adding changesets
adding manifests
adding file changes
added 3 changesets with 3 changes to 3 files (+2 heads)
new changesets 8c68ee086fd0:fcc393352796
updating to branch other
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf ../b
Test -r mine ... mine is ignored:
$ hg clone -u 2 .#other ../b -r mine -r 0 -r 1 -r 2 -b other
adding changesets
adding manifests
adding file changes
added 3 changesets with 3 changes to 3 files (+2 heads)
new changesets 8c68ee086fd0:fcc393352796
updating to branch other
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf ../b
$ hg clone .#other ../b -b default -b mine
adding changesets
adding manifests
adding file changes
added 3 changesets with 3 changes to 3 files (+2 heads)
new changesets 8c68ee086fd0:fcc393352796
updating to branch default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf ../b
$ hg clone .#other ../b
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
new changesets fcc393352796
updating to branch other
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf ../b
$ hg clone -U . ../c -r 1 -r 2 > /dev/null
$ hg clone ../c ../b
updating to branch other
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ rm -rf ../b ../c