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
====================================
Testing head checking code: Case D-2
====================================
Mercurial checks for the introduction of new heads on push. Evolution comes
into play to detect if existing branches on the server are being replaced by
some of the new one we push.
This case is part of a series of tests checking this behavior.
Category D: remote head is "obs-affected" locally, but result is not part of the push
TestCase 1: remote branch has 2 changes, head is pruned, other is rewritten but result is not pushed
.. old-state:
..
.. * 1 changeset branch
..
.. new-state:
..
.. * old head is pruned
.. * 1 new branch succeeding to the other changeset in the old branch
.. * 1 new unrelated branch
..
.. expected-result:
..
.. * push allowed
.. * pushing only the unrelated branch: denied
..
.. graph-summary:
..
.. B ⊗
.. |
.. A ø⇠○ A'
.. |/
.. | ◔ C
.. |/
.. ●
$ . $TESTDIR/testlib/push-checkheads-util.sh
Test setup
----------
$ mkdir D2
$ cd D2
$ setuprepos
creating basic server and client repo
updating to branch default
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd server
$ mkcommit B0
$ cd ../client
$ hg pull
pulling from $TESTTMP/D2/server
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
new changesets d73caddc5533
(run 'hg update' to get a working copy)
$ hg up 0
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ mkcommit A1
created new head
$ hg debugobsolete `getid "desc(A0)" ` `getid "desc(A1)"`
obsoleted 1 changesets
$ hg debugobsolete --record-parents `getid "desc(B0)"`
obsoleted 1 changesets
$ hg up 0
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ mkcommit C0
created new head
$ hg log -G --hidden
@ 0f88766e02d6 (draft): C0
|
| o f6082bc4ffef (draft): A1
|/
| x d73caddc5533 (draft): B0
| |
| x 8aaa48160adc (draft): A0
|/
o 1e4be0697311 (public): root
Actual testing
--------------
$ hg push --rev 'desc(C0)'
pushing to $TESTTMP/D2/server
searching for changes
abort: push creates new remote head 0f88766e02d6!
(merge or see 'hg help push' for details about pushing new heads)
[255]
$ cd ../..