wireprotov2: change how revisions are specified to changesetdata
Right now, we have a handful of arguments for specifying the revisions
whose data should be returned. Defining how all these arguments
interact when various combinations are present is difficult.
This commit establishes a new, generic mechanism for specifying
revisions. Instead of a hodgepodge of arguments defining things, we
have a list of dicts that specify revision selectors. The final set
of revisions is a union of all these selectors.
We implement support for specifying revisions based on:
* An explicit list of changeset revisions
* An explicit list of changeset revisions plus ancestry depth
* A DAG range between changeset roots and heads
If you squint hard enough, this problem has already been solved by
revsets. But I'm reluctant to expose revsets to the wire protocol
because that would require servers to implement a revset parser.
Plus there are security and performance implications: the set
of revision selectors needs to be narrowly and specifically tailored
for what is appropriate to be executing on a server. Perhaps there
would be a way for us to express the "parse tree" of a revset
query, for example. I'm not sure. We can explore this space another
time. For now, the new mechanism should bring sufficient flexibility
while remaining relatively simple.
The selector "types" are prefixed with "changeset" because I plan
to add manifest and file-flavored selectors as well. This will enable
us to e.g. select file revisions based on a range of changeset
revisions.
Differential Revision: https://phab.mercurial-scm.org/D4979
#require no-reposimplestore
$ . "$TESTDIR/narrow-library.sh"
$ hg init master
$ cd master
$ cat >> .hg/hgrc <<EOF
> [narrow]
> serveellipses=True
> EOF
$ for x in `$TESTDIR/seq.py 10`
> do
> echo $x > "f$x"
> hg add "f$x"
> done
$ hg commit -m "Add root files"
$ mkdir d1 d2
$ for x in `$TESTDIR/seq.py 10`
> do
> echo d1/$x > "d1/f$x"
> hg add "d1/f$x"
> echo d2/$x > "d2/f$x"
> hg add "d2/f$x"
> done
$ hg commit -m "Add d1 and d2"
$ for x in `$TESTDIR/seq.py 10`
> do
> echo f$x rev2 > "f$x"
> echo d1/f$x rev2 > "d1/f$x"
> echo d2/f$x rev2 > "d2/f$x"
> hg commit -m "Commit rev2 of f$x, d1/f$x, d2/f$x"
> done
$ cd ..
narrow and shallow clone the d2 directory
$ hg clone --narrow ssh://user@dummy/master shallow --include "d2" --depth 2
requesting all changes
adding changesets
adding manifests
adding file changes
added 4 changesets with 13 changes to 10 files
new changesets *:* (glob)
updating to branch default
10 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd shallow
$ hg log -T '{rev}{if(ellipsis,"...")}: {desc}\n'
3: Commit rev2 of f10, d1/f10, d2/f10
2: Commit rev2 of f9, d1/f9, d2/f9
1: Commit rev2 of f8, d1/f8, d2/f8
0...: Commit rev2 of f7, d1/f7, d2/f7
$ hg update 0
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cat d2/f7 d2/f8
d2/f7 rev2
d2/8
$ cd ..
change every upstream file once
$ cd master
$ for x in `$TESTDIR/seq.py 10`
> do
> echo f$x rev3 > "f$x"
> echo d1/f$x rev3 > "d1/f$x"
> echo d2/f$x rev3 > "d2/f$x"
> hg commit -m "Commit rev3 of f$x, d1/f$x, d2/f$x"
> done
$ cd ..
pull new changes with --depth specified. There were 10 changes to the d2
directory but the shallow pull should only fetch 3.
$ cd shallow
$ hg pull --depth 2
pulling from ssh://user@dummy/master
searching for changes
adding changesets
adding manifests
adding file changes
added 4 changesets with 10 changes to 10 files
new changesets *:* (glob)
(run 'hg update' to get a working copy)
$ hg log -T '{rev}{if(ellipsis,"...")}: {desc}\n'
7: Commit rev3 of f10, d1/f10, d2/f10
6: Commit rev3 of f9, d1/f9, d2/f9
5: Commit rev3 of f8, d1/f8, d2/f8
4...: Commit rev3 of f7, d1/f7, d2/f7
3: Commit rev2 of f10, d1/f10, d2/f10
2: Commit rev2 of f9, d1/f9, d2/f9
1: Commit rev2 of f8, d1/f8, d2/f8
0...: Commit rev2 of f7, d1/f7, d2/f7
$ hg update 4
merging d2/f1
merging d2/f2
merging d2/f3
merging d2/f4
merging d2/f5
merging d2/f6
merging d2/f7
3 files updated, 7 files merged, 0 files removed, 0 files unresolved
$ cat d2/f7 d2/f8
d2/f7 rev3
d2/f8 rev2
$ hg update 7
3 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cat d2/f10
d2/f10 rev3
$ cd ..
cannot clone with zero or negative depth
$ hg clone --narrow ssh://user@dummy/master bad --include "d2" --depth 0
requesting all changes
remote: abort: depth must be positive, got 0
abort: pull failed on remote
[255]
$ hg clone --narrow ssh://user@dummy/master bad --include "d2" --depth -1
requesting all changes
remote: abort: depth must be positive, got -1
abort: pull failed on remote
[255]