filectx.parents: enforce changeid of parent to be in own changectx ancestors
Because of the way filenodes are computed, you can have multiple changesets
"introducing" the same file revision. For example, in the changeset graph
below, changeset 2 and 3 both change a file -to- and -from- the same content.
o 3: content = new
|
| o 2: content = new
|/
o 1: content = old
In such cases, the file revision is create once, when 2 is added, and just reused
for 3. So the file change in '3' (from "old" to "new)" has no linkrev pointing
to it). We'll call this situation "linkrev-shadowing". As the linkrev is used for
optimization purposes when walking a file history, the linkrev-shadowing
results in an unexpected jump to another branch during such a walk.. This leads to
multiple bugs with log, annotate and rename detection.
One element to fix such bugs is to ensure that walking the file history sticks on
the same topology as the changeset's history. For this purpose, we extend the
logic in 'basefilectx.parents' so that it always defines the proper changeset
to associate the parent file revision with. This "proper" changeset has to be an
ancestor of the changeset associated with the child file revision.
This logic is performed in the '_adjustlinkrev' function. This function is
given the starting changeset and all the information regarding the parent file
revision. If the linkrev for the file revision is an ancestor of the starting
changeset, the linkrev is valid and will be used. If it is not, we detected a
topological jump caused by linkrev shadowing, we are going to walk the
ancestors of the starting changeset until we find one setting the file to the
revision we are trying to create.
The performance impact appears acceptable:
- We are walking the changelog once for each filelog traversal (as there should
be no overlap between searches),
- changelog traversal itself is fairly cheap, compared to what is likely going
to be perform on the result on the filelog traversal,
- We only touch the manifest for ancestors touching the file, And such
changesets are likely to be the one introducing the file. (except in
pathological cases involving merge),
- We use manifest diff instead of full manifest unpacking to check manifest
content, so it does not involve applying multiple diffs in most case.
- linkrev shadowing is not the common case.
Tests for fixed issues in log, annotate and rename detection have been
added.
But this changeset does not solve all problems. It fixes -ancestry-
computation, but if the linkrev-shadowed changesets is the starting one, we'll
still get things wrong. We'll have to fix the bootstrapping of such operations
in a later changeset. Also, the usage of `hg log FILE` without --follow still
has issues with linkrev pointing to hidden changesets, because it relies on the
`filelog` revset which implement its own traversal logic that is still to be
fixed.
Thanks goes to:
- Matt Mackall: for nudging me in the right direction
- Julien Cristau and RĂ©mi Cardona: for keep telling me linkrev bug were an
evolution show stopper for 3 years.
- Durham Goode: for finding a new linkrev issue every few weeks
- Mads Kiilerich: for that last rename bug who raise this topic over my
anoyance limit.
#require killdaemons
$ cat > writelines.py <<EOF
> import sys
> path = sys.argv[1]
> args = sys.argv[2:]
> assert (len(args) % 2) == 0
>
> f = file(path, 'wb')
> for i in xrange(len(args)/2):
> count, s = args[2*i:2*i+2]
> count = int(count)
> s = s.decode('string_escape')
> f.write(s*count)
> f.close()
>
> EOF
> cat <<EOF >> $HGRCPATH
> [extensions]
> mq =
> [diff]
> git = 1
> EOF
$ hg init repo
$ cd repo
qimport without file or revision
$ hg qimport
abort: no files or revisions specified
[255]
qimport non-existing-file
$ hg qimport non-existing-file
abort: unable to read file non-existing-file
[255]
qimport null revision
$ hg qimport -r null
abort: revision -1 is not mutable
(see "hg help phases" for details)
[255]
$ hg qseries
import email
$ hg qimport --push -n email - <<EOF
> From: Username in email <test@example.net>
> Subject: [PATCH] Message in email
> Date: Fri, 02 Jan 1970 00:00:00 +0000
>
> Text before patch.
>
> # HG changeset patch
> # User Username in patch <test@example.net>
> # Date 0 0
> # Node ID 1a706973a7d84cb549823634a821d9bdf21c6220
> # Parent 0000000000000000000000000000000000000000
> First line of commit message.
>
> More text in commit message.
> --- confuse the diff detection
>
> diff --git a/x b/x
> new file mode 100644
> --- /dev/null
> +++ b/x
> @@ -0,0 +1,1 @@
> +new file
> Text after patch.
>
> EOF
adding email to series file
applying email
now at: email
hg tip -v
$ hg tip -v
changeset: 0:1a706973a7d8
tag: email
tag: qbase
tag: qtip
tag: tip
user: Username in patch <test@example.net>
date: Thu Jan 01 00:00:00 1970 +0000
files: x
description:
First line of commit message.
More text in commit message.
$ hg qpop
popping email
patch queue now empty
$ hg qdelete email
import URL
$ echo foo >> foo
$ hg add foo
$ hg diff > url.diff
$ hg revert --no-backup foo
$ rm foo
Under unix: file:///foobar/blah
Under windows: file:///c:/foobar/blah
$ patchurl=`pwd | tr '\\\\' /`/url.diff
$ expr "$patchurl" : "\/" > /dev/null || patchurl="/$patchurl"
$ hg qimport file://"$patchurl"
adding url.diff to series file
$ rm url.diff
$ hg qun
url.diff
import patch that already exists
$ echo foo2 >> foo
$ hg add foo
$ hg diff > ../url.diff
$ hg revert --no-backup foo
$ rm foo
$ hg qimport ../url.diff
abort: patch "url.diff" already exists
[255]
$ hg qpush
applying url.diff
now at: url.diff
$ cat foo
foo
$ hg qpop
popping url.diff
patch queue now empty
qimport -f
$ hg qimport -f ../url.diff
adding url.diff to series file
$ hg qpush
applying url.diff
now at: url.diff
$ cat foo
foo2
$ hg qpop
popping url.diff
patch queue now empty
build diff with CRLF
$ python ../writelines.py b 5 'a\n' 5 'a\r\n'
$ hg ci -Am addb
adding b
$ python ../writelines.py b 2 'a\n' 10 'b\n' 2 'a\r\n'
$ hg diff > b.diff
$ hg up -C
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
qimport CRLF diff
$ hg qimport b.diff
adding b.diff to series file
$ hg qpush
applying b.diff
now at: b.diff
try to import --push
$ cat > appendfoo.diff <<EOF
> append foo
>
> diff -r 07f494440405 -r 261500830e46 baz
> --- /dev/null Thu Jan 01 00:00:00 1970 +0000
> +++ b/baz Thu Jan 01 00:00:00 1970 +0000
> @@ -0,0 +1,1 @@
> +foo
> EOF
$ cat > appendbar.diff <<EOF
> append bar
>
> diff -r 07f494440405 -r 261500830e46 baz
> --- a/baz Thu Jan 01 00:00:00 1970 +0000
> +++ b/baz Thu Jan 01 00:00:00 1970 +0000
> @@ -1,1 +1,2 @@
> foo
> +bar
> EOF
$ hg qimport --push appendfoo.diff appendbar.diff
adding appendfoo.diff to series file
adding appendbar.diff to series file
applying appendfoo.diff
applying appendbar.diff
now at: appendbar.diff
$ hg qfin -a
patch b.diff finalized without changeset message
$ touch .hg/patches/2.diff
$ hg qimport -r 'p1(.)::'
abort: patch "2.diff" already exists
[255]
$ hg qapplied
3.diff
$ hg qfin -a
$ rm .hg/patches/2.diff
$ hg qimport -r 'p1(.)::' -P
$ hg qpop -a
popping 3.diff
popping 2.diff
patch queue now empty
$ hg qdel 3.diff
$ hg qdel -k 2.diff
qimport -e
$ hg qimport -e 2.diff
adding 2.diff to series file
$ hg qdel -k 2.diff
qimport -e --name newname oldexisitingpatch
$ hg qimport -e --name this-name-is-better 2.diff
renaming 2.diff to this-name-is-better
adding this-name-is-better to series file
$ hg qser
this-name-is-better
url.diff
qimport -e --name without --force
$ cp .hg/patches/this-name-is-better .hg/patches/3.diff
$ hg qimport -e --name this-name-is-better 3.diff
abort: patch "this-name-is-better" already exists
[255]
$ hg qser
this-name-is-better
url.diff
qimport -e --name with --force
$ hg qimport --force -e --name this-name-is-better 3.diff
renaming 3.diff to this-name-is-better
adding this-name-is-better to series file
$ hg qser
this-name-is-better
url.diff
qimport with bad name, should abort before reading file
$ hg qimport non-existent-file --name .hg
abort: patch name cannot begin with ".hg"
[255]
qimport http:// patch with leading slashes in url
set up hgweb
$ cd ..
$ hg init served
$ cd served
$ echo a > a
$ hg ci -Am patch
adding a
$ hg serve -p $HGPORT -d --pid-file=hg.pid -A access.log -E errors.log
$ cat hg.pid >> $DAEMON_PIDS
$ cd ../repo
$ hg qimport http://localhost:$HGPORT/raw-rev/0///
adding 0 to series file
check qimport phase:
$ hg -q qpush
now at: 0
$ hg phase qparent
1: draft
$ hg qimport -r qparent
$ hg phase qbase
1: draft
$ hg qfinish qbase
$ echo '[mq]' >> $HGRCPATH
$ echo 'secret=true' >> $HGRCPATH
$ hg qimport -r qparent
$ hg phase qbase
1: secret
$ cd ..
$ "$TESTDIR/killdaemons.py" $DAEMON_PIDS