branchmap: skip obsolete revisions while computing heads
It's time to make this part of core Mercurial obsolescence-aware.
Not considering obsolete revisions when computing heads is clearly what
Mercurial should do. But there are a couple of small issues:
- Let's say tip of the repo is obsolete. There are two ways of finding tiprev
for branchcache (both are in use): looking at input data for update() and
looking at computed heads after update(). Previously, repo tip would be
tiprev of the branchcache. With this patch, an obsolete revision can no
longer be tiprev. And depending on what way we use for finding tiprev (input
data vs computed heads) we'll get a different result. This is relevant when
recomputing cache key from cache contents, and may lead to updating cache for
obsolete revisions multiple times (not from scratch, because it still would
be considered valid for a subset of revisions in the repo).
- If all commits on a branch are obsolete, the branchcache will include that
branch, but the list of heads will be empty (that's why there's now `if not
heads` when recomputing tiprev/tipnode from cache contents). Having an entry
for every branch is currently required for notify extension (and
test-notify.t to pass), because notify doesn't handle revsets in its
subscription config very well and will throw an error if e.g. a branch
doesn't exist.
- Cloning static HTTP repos may try to stat() a non-existent obsstore file. The
issue is that we now care about obsolescence during clone, but statichttpvfs
doesn't implement a stat method, so a regular vfs.stat() is used, and it
assumes that file is local and calls os.stat(). During a clone, we're trying
to stat() .hg/store/obsstore, but in static HTTP case we provide a literal
URL to the obsstore file on the remote as if it were a local file path. On
windows it actually results in a failure in test-static-http.t.
The first issue is going to be addressed in a series dedicated to making sure
branchcache is properly and timely written on disk (it wasn't perfect even
before this patch, but there aren't enough tests to demonstrate that). The
second issue will be addressed in a future patch for notify extension that will
make it not raise an exception if a branch doesn't exist. And the third one was
partially addressed in the previous patch in this series and will be properly
fixed in a future patch when this series is accepted.
filteredhash() grows a keyword argument to make sure that branchcache is also
invalidated when there are new obsolete revisions in its repo view. This way
the on-disk cache format is unchanged and compatible between versions (although
it will obviously be recomputed when switching versions before/after this patch
and the repo has obsolete revisions).
There's one test that uses plain `hg up` without arguments while updated to a
pruned commit. To make this test pass, simply return current working directory
parent. Later in this series this code will be replaced by what prune command
does: updating to the closest non-obsolete ancestor.
Test changes:
test-branch-change.t: update branch head and cache update message. The head of
default listed in hg heads is changed because revision 2 was rewritten as 7,
and 1 is the closest ancestor on the same branch, so it's the head of default
now.
The cache invalidation message appears now because of the cache hash change,
since we're now accounting for obsolete revisions. Here's some context:
"served.hidden" repo filter means everything is visible (no filtered
revisions), so before this series branch2-served.hidden file would not contain
any cache hash, only revnum and node. Now it also has a hash when there are
obsolete changesets in the repo. The command that the message appears for is
changing branch of 5 and 6, which are now obsolete, so the cache hash changes.
In general, when cache is simply out-of-date, it can be updated using the old
version as a base. But if cache hash differs, then the cache for that
particular repo filter is recomputed (at least with the current
implementation). This is what happens here.
test-obsmarker-template.t: the pull reports 2 heads changed, but after that the
repo correctly sees only 1. The new message could be better, but it's still an
improvement over the previous one where hg pull suggested merging with an
obsolete revision.
test-obsolete.t: we can see these revisions in hg log --hidden, but they
shouldn't be considered heads even with --hidden.
test-rebase-obsolete{,2}.t: there were new heads created previously after
making new orphan changesets, but they weren't detected. Now we are properly
detecting and reporting them.
test-rebase-obsolete4.t: there's only one head now because the other head is
pruned and was falsely reported before.
test-static-http.t: add obsstore to the list of requested files. This file
doesn't exist on the remotes, but clients want it anyway (they get 404). This
is fine, because there are other nonexistent files that clients request, like
.hg/bookmarks or .hg/cache/tags2-served.
Differential Revision: https://phab.mercurial-scm.org/D12097
Testing changing branch on commits
==================================
Setup
$ cat >> $HGRCPATH << EOF
> [alias]
> glog = log -G -T "{rev}:{node|short} {desc}\n{branch} ({bookmarks})"
> [experimental]
> evolution = createmarkers
> [extensions]
> rebase=
> EOF
$ hg init repo
$ cd repo
$ for ch in a b c d e; do echo foo >> $ch; hg ci -Aqm "Added "$ch; done
$ hg glog
@ 4:aa98ab95a928 Added e
| default ()
o 3:62615734edd5 Added d
| default ()
o 2:28ad74487de9 Added c
| default ()
o 1:29becc82797a Added b
| default ()
o 0:18d04c59bb5d Added a
default ()
$ hg branches
default 4:aa98ab95a928
Try without passing a new branch name
$ hg branch -r .
abort: no branch name specified for the revisions
[10]
Setting an invalid branch name
$ hg branch -r . a:b
abort: ':' cannot be used in a name
[10]
$ hg branch -r . tip
abort: the name 'tip' is reserved
[10]
$ hg branch -r . 1234
abort: cannot use an integer as a name
[10]
Change on non-linear set of commits
$ hg branch -r 2 -r 4 foo
abort: cannot change branch of non-linear revisions
[10]
Change in middle of the stack (linear commits)
$ hg branch -r 1::3 foo
abort: cannot change branch of changeset, as that will orphan 1 descendants
(see 'hg help evolution.instability')
[10]
Change with dirty working directory
$ echo bar > a
$ hg branch -r . foo
abort: uncommitted changes
[20]
$ hg revert --all
reverting a
Change on empty revision set
$ hg branch -r 'draft() - all()' foo
abort: empty revision set
[10]
Changing branch on linear set of commits from head
Without obsmarkers
$ hg branch -r 3:4 foo --config experimental.evolution=!
changed branch on 2 changesets
saved backup bundle to $TESTTMP/repo/.hg/strip-backup/62615734edd5-e86bd13a-branch-change.hg
$ hg glog
@ 4:3938acfb5c0f Added e
| foo ()
o 3:9435da006bdc Added d
| foo ()
o 2:28ad74487de9 Added c
| default ()
o 1:29becc82797a Added b
| default ()
o 0:18d04c59bb5d Added a
default ()
$ hg branches
foo 4:3938acfb5c0f
default 2:28ad74487de9 (inactive)
With obsmarkers
$ hg branch -r 3::4 bar
changed branch on 2 changesets
$ hg glog
@ 6:7c1991464886 Added e
| bar ()
o 5:1ea05e93925f Added d
| bar ()
o 2:28ad74487de9 Added c
| default ()
o 1:29becc82797a Added b
| default ()
o 0:18d04c59bb5d Added a
default ()
$ hg branches
bar 6:7c1991464886
default 2:28ad74487de9 (inactive)
Change branch name to an existing branch
$ hg branch -r . default
abort: a branch of the same name already exists
[10]
Changing on a branch head which is not topological head
$ hg branch -r 2 stable
abort: cannot change branch of changeset, as that will orphan 2 descendants
(see 'hg help evolution.instability')
[10]
Enabling the allowunstable config and trying to change branch on a branch head
which is not a topological head
$ echo "[experimental]" >> .hg/hgrc
$ echo "evolution.allowunstable=yes" >> .hg/hgrc
$ hg branch -r 2 foo
changed branch on 1 changesets
2 new orphan changesets
Changing branch of an obsoleted changeset
$ hg branch -r 4 foobar
abort: hidden revision '4' was rewritten as: 7c1991464886
(use --hidden to access hidden revisions)
[10]
$ hg branch -r 4 --hidden foobar
abort: cannot change branch of 3938acfb5c0f, as that creates content-divergence with 7c1991464886
(add --verbose for details or see 'hg help evolution.instability')
[10]
Make sure bookmark movement is correct
$ hg bookmark b1
$ hg glog -r '.^::'
@ 6:7c1991464886 Added e
| bar (b1)
* 5:1ea05e93925f Added d
| bar ()
~
$ hg branch -r '(.^)::' wat --debug
changing branch of '1ea05e93925f806d875a2163f9b76764be644636' from 'bar' to 'wat'
committing files:
d
committing manifest
committing changelog
new node id is 343660ccab7400da637bd6a211d07f413536d718
changing branch of '7c19914648869f5b02fc7fed31ddee9783fdd680' from 'bar' to 'wat'
committing files:
e
committing manifest
committing changelog
new node id is de1404b45a69f8cc6437d7679033ee33e9efb4ba
moving bookmarks ['b1'] from 7c19914648869f5b02fc7fed31ddee9783fdd680 to de1404b45a69f8cc6437d7679033ee33e9efb4ba
resolving manifests
branchmerge: False, force: False, partial: False
ancestor: 7c1991464886, local: 7c1991464886+, remote: de1404b45a69
starting 4 threads for background file closing (?)
changed branch on 2 changesets
updating the branch cache
invalid branch cache (served): tip differs
invalid branch cache (served.hidden): tip differs
$ hg glog -r '(.^)::'
@ 9:de1404b45a69 Added e
| wat (b1)
* 8:343660ccab74 Added d
| wat ()
~
Make sure phase handling is correct
$ echo foo >> bar
$ hg ci -Aqm "added bar" --secret
1 new orphan changesets
$ hg glog -r .
@ 10:8ad1294c1660 added bar
| wat (b1)
~
$ hg branch -r . secret
changed branch on 1 changesets
$ hg phase -r .
11: secret
$ hg branches
secret 11:38a9b2d53f98
foo 7:8a4729a5e2b8
wat 9:de1404b45a69 (inactive)
default 1:29becc82797a (inactive)
$ hg branch
secret
Changing branch of another head, different from one on which we are
$ hg glog
@ 11:38a9b2d53f98 added bar
| secret (b1)
* 9:de1404b45a69 Added e
| wat ()
* 8:343660ccab74 Added d
| wat ()
| o 7:8a4729a5e2b8 Added c
| | foo ()
x | 2:28ad74487de9 Added c
|/ default ()
o 1:29becc82797a Added b
| default ()
o 0:18d04c59bb5d Added a
default ()
$ hg branch
secret
$ hg branch -r 7 foobar
changed branch on 1 changesets
The current branch must be preserved
$ hg branch
secret
Changing branch on multiple heads at once
$ hg rebase -s 8 -d 12 --keepbranches -q
$ hg rebase -s 14 -d 1 --keepbranches -q
$ hg branch -r 0: stable
changed branch on 6 changesets
$ hg glog
@ 23:6a5ddbcfb870 added bar
| stable (b1)
o 22:baedc6e98a67 Added e
| stable ()
| o 21:99ac7bf8aad1 Added d
| | stable ()
| o 20:0ecb4d39c4bd Added c
|/ stable ()
o 19:fd45b986b109 Added b
| stable ()
o 18:204d2769eca2 Added a
stable ()
$ hg branches
stable 23:6a5ddbcfb870
$ hg branch
stable
Changing to same branch is no-op
$ hg branch -r 19::21 stable
changed branch on 0 changesets
Changing branch name to existing branch name if the branch of parent of root of
revs is same as the new branch name
$ hg branch -r 20::21 bugfix
changed branch on 2 changesets
$ hg glog
o 25:714defe1cf34 Added d
| bugfix ()
o 24:98394def28fc Added c
| bugfix ()
| @ 23:6a5ddbcfb870 added bar
| | stable (b1)
| o 22:baedc6e98a67 Added e
|/ stable ()
o 19:fd45b986b109 Added b
| stable ()
o 18:204d2769eca2 Added a
stable ()
$ hg branch -r 24:25 stable
changed branch on 2 changesets
$ hg glog
o 27:4ec342341562 Added d
| stable ()
o 26:83f48859c2de Added c
| stable ()
| @ 23:6a5ddbcfb870 added bar
| | stable (b1)
| o 22:baedc6e98a67 Added e
|/ stable ()
o 19:fd45b986b109 Added b
| stable ()
o 18:204d2769eca2 Added a
stable ()
Changing branch of a merge commit
$ hg branch -q ghi
$ echo f > f
$ hg ci -qAm 'Added f'
$ hg up -q 27
$ hg branch -q jkl
$ echo g > g
$ hg ci -qAm 'Added g'
$ hg glog -r 'heads(:)'
@ 29:6bc1c6c2c9da Added g
| jkl ()
~
o 28:2f1019bd29d2 Added f
| ghi (b1)
~
$ hg branch -q default
$ hg merge -r 28
4 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg branch -r . abcd
abort: outstanding uncommitted merge
[20]
$ hg ci -m "Merge commit"
$ hg glog -r 'parents(.)::'
@ 30:4d56e6b1eb6b Merge commit
|\ default ()
| o 29:6bc1c6c2c9da Added g
| | jkl ()
| ~
o 28:2f1019bd29d2 Added f
| ghi (b1)
~
$ hg branch -r . ghi
0 files updated, 0 files merged, 4 files removed, 0 files unresolved
changed branch on 1 changesets
$ hg branch -r . jkl
changed branch on 1 changesets
$ hg branch -r . default
changed branch on 1 changesets
$ hg branch -r . stable
abort: a branch of the same name already exists
[10]
$ hg branch -r . stable --force
changed branch on 1 changesets
$ hg branches
stable 34:d1c2addda4a2
jkl 29:6bc1c6c2c9da (inactive)
ghi 28:2f1019bd29d2 (inactive)
Changing branch on public changeset
$ hg phase -r . -p
$ hg branch -r . def
abort: cannot change branch of public changesets: d1c2addda4a2
(see 'hg help phases' for details)
[10]
Merge commit with conflicts, with evolution and without
$ mklozenge() {
> echo foo > a
> hg ci -qAm foo
> echo bar > a
> hg ci -qm bar
> hg up -q '.^'
> echo baz > a
> hg ci -qm baz
> hg merge -q -t :local
> echo neither > a
> hg ci -qm neither
> }
$ cd ..
$ hg init merge-with-evolution
$ cd merge-with-evolution
$ mklozenge
$ hg branch -r '(.^)::' abc
changed branch on 2 changesets
$ hg glog
@ 5:c07fa8b34d54 neither
|\ abc ()
| o 4:f2aa51777cc9 baz
| | abc ()
o | 1:2e33c4f0856b bar
|/ default ()
o 0:91cfb6004abf foo
default ()
$ hg cat a
neither
$ cd ..
$ hg init merge-without-evolution
$ cd merge-without-evolution
$ mklozenge
$ cat > .hg/hgrc << EOF
> [experimental]
> evolution = no
> evolution.allowunstable = no
> EOF
$ hg branch -r '(.^)::' abc
changed branch on 2 changesets
saved backup bundle to $TESTTMP/merge-without-evolution/.hg/strip-backup/9a3a2af368f4-8db1a361-branch-change.hg
$ hg glog
@ 3:c07fa8b34d54 neither
|\ abc ()
| o 2:f2aa51777cc9 baz
| | abc ()
o | 1:2e33c4f0856b bar
|/ default ()
o 0:91cfb6004abf foo
default ()
$ hg cat a
neither