annotate: increase refcount of each revisions correctly (issue3841)
Before this patch, refcount (managed in "needed") of parents of each
revisions in "visit" is increased, only when parent is not annotated
yet (examined by "p not in hist").
But this causes less refcount of the revision like "A" in the tree
below ("A" is assumed as the second parent of "C"):
A --- B --- C
\ /
\-----/
Steps of annotation for "C" in this case are shown below:
1. for "C"
1.1 increase refcount of "B"
1.2 increase refcount of "A" (=> 1)
1.3 defer annotation for "C"
2. for "A"
2.1 annotate for "A" (=> put result into "hist[A]")
2.2 clear "pcache[A]" ("pcache[A] = []")
3. for "B"
3.1 not increase refcount of "A", because "A not in hist" is False
3.2 annotate for "B"
3.3 decrease refcount of "A" (=> 0)
3.4 delete "hist[A]", even though "A" is still needed by "C"
3.5 clear "pcache[B]"
4. for "C", again
4.1 not increase refcount of "B", because "B not in hist" is False
4.2 increase refcount of "A" (=> 1)
4.3 defer annotation for "C"
5. for "A", again
5.1 annotate for "A" (=> put result into "hist[A]", again)
5.2 clear "pcache[A]"
6. for "C", once again
6.1 not increase refcount of "B", because "B not in hist" is False
6.2 not increase refcount of "A", because "A not in hist" is False
6.3 annotate for "C"
6.4 decrease refcount of "A", and delete "hist[A]"
6.5 decrease refcount of "B", and delete "hist[B]"
6.6 clear "pcache[C]"
At step (5.1), annotation for "A" mis-recognizes that all lines are
created at "A", because "pcache[A]" already cleared at step (2.2)
prevents from scanning ancestors of "A".
So, annotation for "C" or its descendants loses information about "A"
or its ancestors.
The root cause of this problem is that refcount of "A" is decreased at
step (3.3), even though it isn't increased at step (3.1).
To increase refcount correctly, this patch increases refcount of each
parents of each revisions:
- regardless of "p not in hist" or not, and
- only once for each revisions in "visit" (by "not pcached")
In fact, this problem should occur only on legacy repositories in
which a filelog includes the merging between the revision and its
ancestor (as the second parent), because:
- tree is scanned in depth-first
without such merging, revisions in "visit" refer different
revisions as parent each other
- recent Mercurial doesn't allow such merging
changelog and manifest can include such merging someway, but
filelogs can't, because "localrepository._filecommit()" converts
such merging request to linear history.
This patch tests merging cases below: these cases are from filelog of
"mercurial/commands.py" in the repository of Mercurial itself.
- both parents are same
10 --- 11 --- 12
\_/
filelogrev: changesetid:
10 00ea3613f82c
11 fc4a6e5b5812
12 4f802588cdfb
- the second parent is also ancestor of the first one
37 --- 38 --- 39 --- 40
\________/
filelogrev: changesetid:
37 f8d56da6ac8f
38 38919e1c254d
39 d3400605d246
40 f06a4a3b86a7
$ cat <<EOF > merge
> import sys, os
>
> try:
> import msvcrt
> msvcrt.setmode(sys.stdout.fileno(), os.O_BINARY)
> msvcrt.setmode(sys.stderr.fileno(), os.O_BINARY)
> except ImportError:
> pass
>
> print "merging for", os.path.basename(sys.argv[1])
> EOF
$ HGMERGE="python ../merge"; export HGMERGE
$ hg init t
$ cd t
$ echo This is file a1 > a
$ hg add a
$ hg commit -m "commit #0"
$ echo This is file b1 > b
$ hg add b
$ hg commit -m "commit #1"
$ hg update 0
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ echo This is file c1 > c
$ hg add c
$ hg commit -m "commit #2"
created new head
$ echo This is file b1 > b
no merges expected
$ hg merge -P 1
changeset: 1:b8bb4a988f25
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: commit #1
$ hg merge 1
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg diff --nodates
diff -r 49035e18a8e6 b
--- /dev/null
+++ b/b
@@ -0,0 +1,1 @@
+This is file b1
$ hg status
M b
$ cd ..; rm -r t
$ hg init t
$ cd t
$ echo This is file a1 > a
$ hg add a
$ hg commit -m "commit #0"
$ echo This is file b1 > b
$ hg add b
$ hg commit -m "commit #1"
$ hg update 0
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ echo This is file c1 > c
$ hg add c
$ hg commit -m "commit #2"
created new head
$ echo This is file b2 > b
merge should fail
$ hg merge 1
b: untracked file differs
abort: untracked files in working directory differ from files in requested revision
[255]
merge of b expected
$ hg merge -f 1
merging b
merging for b
0 files updated, 1 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg diff --nodates
diff -r 49035e18a8e6 b
--- /dev/null
+++ b/b
@@ -0,0 +1,1 @@
+This is file b2
$ hg status
M b
$ cd ..; rm -r t
$ hg init t
$ cd t
$ echo This is file a1 > a
$ hg add a
$ hg commit -m "commit #0"
$ echo This is file b1 > b
$ hg add b
$ hg commit -m "commit #1"
$ echo This is file b22 > b
$ hg commit -m "commit #2"
$ hg update 1
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo This is file c1 > c
$ hg add c
$ hg commit -m "commit #3"
created new head
Contents of b should be "this is file b1"
$ cat b
This is file b1
$ echo This is file b22 > b
merge fails
$ hg merge 2
abort: outstanding uncommitted changes
(use 'hg status' to list changes)
[255]
merge expected!
$ hg merge -f 2
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg diff --nodates
diff -r 85de557015a8 b
--- a/b
+++ b/b
@@ -1,1 +1,1 @@
-This is file b1
+This is file b22
$ hg status
M b
$ cd ..; rm -r t
$ hg init t
$ cd t
$ echo This is file a1 > a
$ hg add a
$ hg commit -m "commit #0"
$ echo This is file b1 > b
$ hg add b
$ hg commit -m "commit #1"
$ echo This is file b22 > b
$ hg commit -m "commit #2"
$ hg update 1
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo This is file c1 > c
$ hg add c
$ hg commit -m "commit #3"
created new head
$ echo This is file b33 > b
merge of b should fail
$ hg merge 2
abort: outstanding uncommitted changes
(use 'hg status' to list changes)
[255]
merge of b expected
$ hg merge -f 2
merging b
merging for b
0 files updated, 1 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg diff --nodates
diff -r 85de557015a8 b
--- a/b
+++ b/b
@@ -1,1 +1,1 @@
-This is file b1
+This is file b33
$ hg status
M b
Test for issue2364
$ hg up -qC .
$ hg rm b
$ hg ci -md
$ hg revert -r -2 b
$ hg up -q -- -2
$ cd ..