repoview: discard filtered changelog if index isn't shared with unfiltered
Before this patch, revisions rollbacked at failure of previous
transaction might be visible at subsequent operations unintentionally,
if repoview object is reused even after failure of transaction:
e.g. command server and HTTP server are typical cases.
'repoview' uses the tuple of values below of unfiltered changelog as
"the key" to examine validity of filtered changelog cache.
- length
- tip node
- filtered revisions (as hashed value)
- '_delayed' field
'repoview' compares between "the key" of unfiltered changelog at
previous caching and now, and reuses filtered changelog cache if no
change is detected.
But this comparison indicates only that there is no change between
unfiltered 'repo.changelog' at last caching and now, but not that
filtered changelog cache is valid for current unfiltered one.
'repoview' uses "shallow copy" of unfiltered changelog to create
filtered changelog cache. In this case, 'index' buffer of unfiltered
changelog is also referred by filtered changelog.
At failure of transaction, unfiltered changelog itself is invalidated
(= un-referred) on the 'repo' side (see
0a7610758c42 also). But
'index' of it still contains revisions to be rollbacked at this
failure, and is referred by filtered changelog.
Therefore, even if there is no change between unfiltered
'repo.changelog' at last caching and now, steps below makes rollbacked
revisions visible via filtered changelog unintentionally.
1. instantiate unfiltered changelog as 'repo.changelog'
(call it CL1)
2. make filtered (= shallow copy of) CL1
(call it FCL1)
3. cache FCL1 with "the key" of CL1
4. revisions are appended to 'index', which is shared by CL1 and FCL1
5. invalidate 'repo.changelog' (= CL1) at failure of transaction
6. instantiate 'repo.changelog' again at next operation
(call it CL2)
CL2 doesn't have revisions added at (4), because it is
instantiated from '00changelog.i', which isn't changed while
failed transaction.
7. compare between "the key" of CL1 and CL2
8. FCL1 cached at (3) is reused, because comparison at (7) doesn't
detect change between CL1 at (1) and CL2
9. revisions rollbacked at (5) are visible via FCL1 unintentionally,
because FCL1 still refers 'index' changed at (4)
The root cause of this issue is that there is no examination about
validity of filtered changelog cache against current unfiltered one.
This patch discards filtered changelog cache, if its 'index' object
isn't shared with unfiltered one.
BTW, at the time of this patch, redundant truncation of
'00changelog.i' at failure of transaction (see
0a7610758c42 for
detail) often prevents "hg serve" from making already rollbacked
revisions visible, because updating timestamps of '00changelog.i' by
truncation makes "hg serve" discard old repoview object with invalid
filtered changelog cache.
This is reason why this issue is overlooked before this patch, even
though test-bundle2-exchange.t has tests in similar situation: failure
of "hg push" via HTTP by pretxnclose hook on server side doesn't
prevent subsequent commands from looking up outgoing revisions
correctly.
But timestamp on the filesystem doesn't have enough resolution for
recent computation power, and it can't be assumed that this avoidance
always works as expected.
Therefore, without this patch, this issue might appear occasionally.
Test basic functionality of url#rev syntax
$ hg init repo
$ cd repo
$ echo a > a
$ hg ci -qAm 'add a'
$ hg branch foo
marked working directory as branch foo
(branches are permanent and global, did you want a bookmark?)
$ echo >> a
$ hg ci -m 'change a'
$ cd ..
$ hg clone 'repo#foo' clone
adding changesets
adding manifests
adding file changes
added 2 changesets with 2 changes to 1 files
updating to branch foo
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg --cwd clone heads
changeset: 1:cd2a86ecc814
branch: foo
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: change a
changeset: 0:1f0dee641bb7
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: add a
$ hg --cwd clone parents
changeset: 1:cd2a86ecc814
branch: foo
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: change a
$ cat clone/.hg/hgrc
# example repository config (see "hg help config" for more info)
[paths]
default = $TESTTMP/repo#foo (glob)
# path aliases to other clones of this repo in URLs or filesystem paths
# (see "hg help config.paths" for more info)
#
# default-push = ssh://jdoe@example.net/hg/jdoes-fork
# my-fork = ssh://jdoe@example.net/hg/jdoes-fork
# my-clone = /home/jdoe/jdoes-clone
[ui]
# name and email (local to this repository, optional), e.g.
# username = Jane Doe <jdoe@example.com>
Changing original repo:
$ cd repo
$ echo >> a
$ hg ci -m 'new head of branch foo'
$ hg up -qC default
$ echo bar > bar
$ hg ci -qAm 'add bar'
$ hg log
changeset: 3:4cd725637392
tag: tip
parent: 0:1f0dee641bb7
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: add bar
changeset: 2:faba9097cad4
branch: foo
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: new head of branch foo
changeset: 1:cd2a86ecc814
branch: foo
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: change a
changeset: 0:1f0dee641bb7
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: add a
$ hg -q outgoing '../clone'
2:faba9097cad4
3:4cd725637392
$ hg summary --remote --config paths.default='../clone'
parent: 3:4cd725637392 tip
add bar
branch: default
commit: (clean)
update: (current)
phases: 4 draft
remote: 2 outgoing
$ hg -q outgoing '../clone#foo'
2:faba9097cad4
$ hg summary --remote --config paths.default='../clone#foo'
parent: 3:4cd725637392 tip
add bar
branch: default
commit: (clean)
update: (current)
phases: 4 draft
remote: 1 outgoing
$ hg -q --cwd ../clone incoming '../repo#foo'
2:faba9097cad4
$ hg --cwd ../clone summary --remote --config paths.default='../repo#foo'
parent: 1:cd2a86ecc814 tip
change a
branch: foo
commit: (clean)
update: (current)
remote: 1 or more incoming
$ hg -q push '../clone#foo'
$ hg --cwd ../clone heads
changeset: 2:faba9097cad4
branch: foo
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: new head of branch foo
changeset: 0:1f0dee641bb7
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: add a
$ hg -q --cwd ../clone incoming '../repo#foo'
[1]
$ hg --cwd ../clone summary --remote --config paths.default='../repo#foo'
parent: 1:cd2a86ecc814
change a
branch: foo
commit: (clean)
update: 1 new changesets (update)
remote: (synced)
$ cd ..
$ cd clone
$ hg rollback
repository tip rolled back to revision 1 (undo push)
$ hg -q incoming
2:faba9097cad4
$ hg -q pull
$ hg heads
changeset: 2:faba9097cad4
branch: foo
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: new head of branch foo
changeset: 0:1f0dee641bb7
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: add a
Pull should not have updated:
$ hg parents -q
1:cd2a86ecc814
Going back to the default branch:
$ hg up -C 0
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg parents
changeset: 0:1f0dee641bb7
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: add a
No new revs, no update:
$ hg pull -qu
$ hg parents -q
0:1f0dee641bb7
$ hg rollback
repository tip rolled back to revision 1 (undo pull)
$ hg parents -q
0:1f0dee641bb7
Pull -u takes us back to branch foo:
$ hg pull -qu
$ hg parents
changeset: 2:faba9097cad4
branch: foo
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: new head of branch foo
$ hg rollback
repository tip rolled back to revision 1 (undo pull)
working directory now based on revision 0
$ hg up -C 0
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg parents -q
0:1f0dee641bb7
$ hg heads -q
1:cd2a86ecc814
0:1f0dee641bb7
$ hg pull -qur default default
$ hg parents
changeset: 3:4cd725637392
tag: tip
parent: 0:1f0dee641bb7
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: add bar
$ hg heads
changeset: 3:4cd725637392
tag: tip
parent: 0:1f0dee641bb7
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: add bar
changeset: 2:faba9097cad4
branch: foo
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: new head of branch foo
Test handling of invalid urls
$ hg id http://foo/?bar
abort: unsupported URL component: "bar"
[255]
$ cd ..
Test handling common incoming revisions between "default" and
"default-push"
$ hg -R clone rollback
repository tip rolled back to revision 1 (undo pull)
working directory now based on revision 0
$ cd repo
$ hg update -q -C default
$ echo modified >> bar
$ hg commit -m "new head to push current default head"
$ hg -q push -r ".^1" '../clone'
$ hg -q outgoing '../clone'
2:faba9097cad4
4:d515801a8f3d
$ hg summary --remote --config paths.default='../clone#default' --config paths.default-push='../clone#foo'
parent: 4:d515801a8f3d tip
new head to push current default head
branch: default
commit: (clean)
update: (current)
phases: 1 draft
remote: 1 outgoing
$ hg summary --remote --config paths.default='../clone#foo' --config paths.default-push='../clone'
parent: 4:d515801a8f3d tip
new head to push current default head
branch: default
commit: (clean)
update: (current)
phases: 1 draft
remote: 2 outgoing
$ hg summary --remote --config paths.default='../clone' --config paths.default-push='../clone#foo'
parent: 4:d515801a8f3d tip
new head to push current default head
branch: default
commit: (clean)
update: (current)
phases: 1 draft
remote: 1 outgoing
$ hg clone -q -r 0 . ../another
$ hg -q outgoing '../another#default'
3:4cd725637392
4:d515801a8f3d
$ hg summary --remote --config paths.default='../another#default' --config paths.default-push='../clone#default'
parent: 4:d515801a8f3d tip
new head to push current default head
branch: default
commit: (clean)
update: (current)
phases: 1 draft
remote: 1 outgoing
$ cd ..