scmutil: add file object wrapper class to check ambiguity at closing
In Mercurial source tree, opening a file in "a"/"a+" mode like below
doesn't specify atomictemp=True for vfs, and this avoids file stat
ambiguity check by atomictempfile.
- writing changes out in revlog layer uses "a+" mode
- truncation in repair.strip() uses "a" mode
- truncation in transaction._playback() uses "a" mode
If steps below occurs at "the same time in sec", all of mtime, ctime
and size are same between (1) and (3).
1. append data to revlog-style file (and close transaction)
2. discard appended data by truncation (strip or rollback)
3. append same size but different data to revlog-style file again
Therefore, cache validation doesn't work after (3) as expected.
This patch adds file object wrapper class checkambigatclosing to check
(and get rid of) ambiguity at closing. It is used by vfs in subsequent
patch.
This is a part of ExactCacheValidationPlan.
https://www.mercurial-scm.org/wiki/ExactCacheValidationPlan
BTW, checkambigatclosing is tested in test-filecache.py, even though
it doesn't use filecache itself, because filecache assumes that file
stat ambiguity never occurs (and there is no another test-*.py related
to filecache).
$ cat >> $HGRCPATH <<EOF
> [extensions]
> rebase=
>
> [alias]
> tglog = log -G --template "{rev}: '{desc}' {branches}\n"
> EOF
$ hg init a
$ cd a
$ echo C1 > C1
$ hg ci -Am C1
adding C1
$ echo C2 > C2
$ hg ci -Am C2
adding C2
$ cd ..
$ hg clone a b
updating to branch default
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg clone a c
updating to branch default
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd b
$ echo L1 > L1
$ hg ci -Am L1
adding L1
$ cd ../a
$ echo R1 > R1
$ hg ci -Am R1
adding R1
$ cd ../b
Now b has one revision to be pulled from a:
$ hg pull --rebase
pulling from $TESTTMP/a (glob)
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files (+1 heads)
rebasing 2:ff8d69a621f9 "L1"
saved backup bundle to $TESTTMP/b/.hg/strip-backup/ff8d69a621f9-160fa373-backup.hg (glob)
$ hg tglog
@ 3: 'L1'
|
o 2: 'R1'
|
o 1: 'C2'
|
o 0: 'C1'
Re-run:
$ hg pull --rebase
pulling from $TESTTMP/a (glob)
searching for changes
no changes found
Invoke pull --rebase and nothing to rebase:
$ cd ../c
$ hg book norebase
$ hg pull --rebase
pulling from $TESTTMP/a (glob)
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
nothing to rebase - updating instead
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
updating bookmark norebase
$ hg tglog -l 1
@ 2: 'R1'
|
~
pull --rebase --update should ignore --update:
$ hg pull --rebase --update
pulling from $TESTTMP/a (glob)
searching for changes
no changes found
pull --rebase doesn't update if nothing has been pulled:
$ hg up -q 1
$ hg pull --rebase
pulling from $TESTTMP/a (glob)
searching for changes
no changes found
$ hg tglog -l 1
o 2: 'R1'
|
~
$ cd ..
pull --rebase works when a specific revision is pulled (issue3619)
$ cd a
$ hg tglog
@ 2: 'R1'
|
o 1: 'C2'
|
o 0: 'C1'
$ echo R2 > R2
$ hg ci -Am R2
adding R2
$ echo R3 > R3
$ hg ci -Am R3
adding R3
$ cd ../c
$ hg tglog
o 2: 'R1'
|
@ 1: 'C2'
|
o 0: 'C1'
$ echo L1 > L1
$ hg ci -Am L1
adding L1
created new head
$ hg pull --rev tip --rebase
pulling from $TESTTMP/a (glob)
searching for changes
adding changesets
adding manifests
adding file changes
added 2 changesets with 2 changes to 2 files
rebasing 3:ff8d69a621f9 "L1"
saved backup bundle to $TESTTMP/c/.hg/strip-backup/ff8d69a621f9-160fa373-backup.hg (glob)
$ hg tglog
@ 5: 'L1'
|
o 4: 'R3'
|
o 3: 'R2'
|
o 2: 'R1'
|
o 1: 'C2'
|
o 0: 'C1'
pull --rebase works with bundle2 turned on
$ cd ../a
$ echo R4 > R4
$ hg ci -Am R4
adding R4
$ hg tglog
@ 5: 'R4'
|
o 4: 'R3'
|
o 3: 'R2'
|
o 2: 'R1'
|
o 1: 'C2'
|
o 0: 'C1'
$ cd ../c
$ hg pull --rebase
pulling from $TESTTMP/a (glob)
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files (+1 heads)
rebasing 5:518d153c0ba3 "L1"
saved backup bundle to $TESTTMP/c/.hg/strip-backup/518d153c0ba3-73407f14-backup.hg (glob)
$ hg tglog
@ 6: 'L1'
|
o 5: 'R4'
|
o 4: 'R3'
|
o 3: 'R2'
|
o 2: 'R1'
|
o 1: 'C2'
|
o 0: 'C1'
pull --rebase only update if there is nothing to rebase
$ cd ../a
$ echo R5 > R5
$ hg ci -Am R5
adding R5
$ hg tglog
@ 6: 'R5'
|
o 5: 'R4'
|
o 4: 'R3'
|
o 3: 'R2'
|
o 2: 'R1'
|
o 1: 'C2'
|
o 0: 'C1'
$ cd ../c
$ echo L2 > L2
$ hg ci -Am L2
adding L2
$ hg up 'desc(L1)'
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ hg pull --rebase
pulling from $TESTTMP/a (glob)
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files (+1 heads)
rebasing 6:0d0727eb7ce0 "L1"
rebasing 7:c1f58876e3bf "L2"
saved backup bundle to $TESTTMP/c/.hg/strip-backup/0d0727eb7ce0-ef61ccb2-backup.hg (glob)
$ hg tglog
o 8: 'L2'
|
@ 7: 'L1'
|
o 6: 'R5'
|
o 5: 'R4'
|
o 4: 'R3'
|
o 3: 'R2'
|
o 2: 'R1'
|
o 1: 'C2'
|
o 0: 'C1'
pull --rebase update (no rebase) use proper update:
- warn about other head.
$ cd ../a
$ echo R6 > R6
$ hg ci -Am R6
adding R6
$ cd ../c
$ hg up 'desc(R5)'
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ hg pull --rebase
pulling from $TESTTMP/a (glob)
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files (+1 heads)
nothing to rebase - updating instead
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
1 other heads for branch "default"
$ hg tglog
@ 9: 'R6'
|
| o 8: 'L2'
| |
| o 7: 'L1'
|/
o 6: 'R5'
|
o 5: 'R4'
|
o 4: 'R3'
|
o 3: 'R2'
|
o 2: 'R1'
|
o 1: 'C2'
|
o 0: 'C1'
Multiple pre-existing heads on the branch
-----------------------------------------
Pull bring content, but nothing on the current branch, we should not consider
pre-existing heads.
$ cd ../a
$ hg branch unrelatedbranch
marked working directory as branch unrelatedbranch
(branches are permanent and global, did you want a bookmark?)
$ echo B1 > B1
$ hg commit -Am B1
adding B1
$ cd ../c
$ hg up 'desc(L2)'
2 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ hg pull --rebase
pulling from $TESTTMP/a (glob)
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
nothing to rebase
There is two local heads and we pull a third one.
The second local head should not confuse the `hg pull rebase`.
$ hg up 'desc(R6)'
1 files updated, 0 files merged, 2 files removed, 0 files unresolved
$ echo M1 > M1
$ hg commit -Am M1
adding M1
$ cd ../a
$ hg up 'desc(R6)'
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ echo R7 > R7
$ hg commit -Am R7
adding R7
$ cd ../c
$ hg up 'desc(L2)'
2 files updated, 0 files merged, 2 files removed, 0 files unresolved
$ hg pull --rebase
pulling from $TESTTMP/a (glob)
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files (+1 heads)
rebasing 7:864e0a2d2614 "L1"
rebasing 8:6dc0ea5dcf55 "L2"
saved backup bundle to $TESTTMP/c/.hg/strip-backup/864e0a2d2614-2f72c89c-backup.hg (glob)
$ hg tglog
@ 12: 'L2'
|
o 11: 'L1'
|
o 10: 'R7'
|
| o 9: 'M1'
|/
| o 8: 'B1' unrelatedbranch
|/
o 7: 'R6'
|
o 6: 'R5'
|
o 5: 'R4'
|
o 4: 'R3'
|
o 3: 'R2'
|
o 2: 'R1'
|
o 1: 'C2'
|
o 0: 'C1'