view tests/test-convert-bzr.t @ 23702:c48924787eaa

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 Rémi 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.

  $ . "$TESTDIR/bzr-definitions"

create and rename on the same file in the same step

  $ mkdir test-createandrename
  $ cd test-createandrename
  $ bzr init -q source

test empty repo conversion (issue3233)

  $ hg convert source source-hg
  initializing destination source-hg repository
  scanning source...
  sorting...
  converting...

back to the rename stuff

  $ cd source
  $ echo a > a
  $ echo c > c
  $ echo e > e
  $ bzr add -q a c e
  $ bzr commit -q -m 'Initial add: a, c, e'
  $ bzr mv a b
  a => b
  $ bzr mv c d
  c => d
  $ bzr mv e f
  e => f
  $ echo a2 >> a
  $ mkdir e
  $ bzr add -q a e
  $ bzr commit -q -m 'rename a into b, create a, rename c into d'
  $ cd ..
  $ hg convert source source-hg
  scanning source...
  sorting...
  converting...
  1 Initial add: a, c, e
  0 rename a into b, create a, rename c into d
  $ glog -R source-hg
  o  1@source "rename a into b, create a, rename c into d" files: a b c d e f
  |
  o  0@source "Initial add: a, c, e" files: a c e
  

manifest

  $ hg manifest -R source-hg -r tip
  a
  b
  d
  f

test --rev option

  $ hg convert -r 1 source source-1-hg
  initializing destination source-1-hg repository
  scanning source...
  sorting...
  converting...
  0 Initial add: a, c, e
  $ glog -R source-1-hg
  o  0@source "Initial add: a, c, e" files: a c e
  

test with filemap

  $ cat > filemap <<EOF
  > exclude a
  > EOF
  $ hg convert --filemap filemap source source-filemap-hg
  initializing destination source-filemap-hg repository
  scanning source...
  sorting...
  converting...
  1 Initial add: a, c, e
  0 rename a into b, create a, rename c into d
  $ hg -R source-filemap-hg manifest -r tip
  b
  d
  f

convert from lightweight checkout

  $ bzr checkout --lightweight source source-light
  $ hg convert -s bzr source-light source-light-hg
  initializing destination source-light-hg repository
  warning: lightweight checkouts may cause conversion failures, try with a regular branch instead.
  $TESTTMP/test-createandrename/source-light does not look like a Bazaar repository
  abort: source-light: missing or unsupported repository
  [255]

extract timestamps that look just like hg's {date|isodate}:
yyyy-mm-dd HH:MM zzzz (no seconds!)
compare timestamps

  $ cd source
  $ bzr log | \
  >   sed '/timestamp/!d;s/.\{15\}\([0-9: -]\{16\}\):.. \(.[0-9]\{4\}\)/\1 \2/' \
  >   > ../bzr-timestamps
  $ cd ..
  $ hg -R source-hg log --template "{date|isodate}\n" > hg-timestamps
  $ cmp bzr-timestamps hg-timestamps || diff -u bzr-timestamps hg-timestamps
  $ cd ..

merge

  $ mkdir test-merge
  $ cd test-merge
  $ cat > helper.py <<EOF
  > import sys
  > from bzrlib import workingtree
  > wt = workingtree.WorkingTree.open('.')
  > 
  > message, stamp = sys.argv[1:]
  > wt.commit(message, timestamp=int(stamp))
  > EOF
  $ bzr init -q source
  $ cd source
  $ echo content > a
  $ echo content2 > b
  $ bzr add -q a b
  $ bzr commit -q -m 'Initial add'
  $ cd ..
  $ bzr branch -q source source-improve
  $ cd source
  $ echo more >> a
  $ python ../helper.py 'Editing a' 100
  $ cd ../source-improve
  $ echo content3 >> b
  $ python ../helper.py 'Editing b' 200
  $ cd ../source
  $ bzr merge -q ../source-improve
  $ bzr commit -q -m 'Merged improve branch'
  $ cd ..
  $ hg convert --datesort source source-hg
  initializing destination source-hg repository
  scanning source...
  sorting...
  converting...
  3 Initial add
  2 Editing a
  1 Editing b
  0 Merged improve branch
  $ glog -R source-hg
  o    3@source "Merged improve branch" files:
  |\
  | o  2@source-improve "Editing b" files: b
  | |
  o |  1@source "Editing a" files: a
  |/
  o  0@source "Initial add" files: a b
  
  $ cd ..

#if symlink execbit

symlinks and executable files

  $ mkdir test-symlinks
  $ cd test-symlinks
  $ bzr init -q source
  $ cd source
  $ touch program
  $ chmod +x program
  $ ln -s program altname
  $ mkdir d
  $ echo a > d/a
  $ ln -s a syma
  $ bzr add -q altname program syma d/a
  $ bzr commit -q -m 'Initial setup'
  $ touch newprog
  $ chmod +x newprog
  $ rm altname
  $ ln -s newprog altname
  $ chmod -x program
  $ bzr add -q newprog
  $ bzr commit -q -m 'Symlink changed, x bits changed'
  $ cd ..
  $ hg convert source source-hg
  initializing destination source-hg repository
  scanning source...
  sorting...
  converting...
  1 Initial setup
  0 Symlink changed, x bits changed
  $ manifest source-hg 0
  % manifest of 0
  644 @ altname
  644   d/a
  755 * program
  644 @ syma
  $ manifest source-hg tip
  % manifest of tip
  644 @ altname
  644   d/a
  755 * newprog
  644   program
  644 @ syma

test the symlinks can be recreated

  $ cd source-hg
  $ hg up
  5 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg cat syma; echo
  a
  $ cd ../..

#endif

Multiple branches

  $ bzr init-repo -q --no-trees repo
  $ bzr init -q repo/trunk
  $ bzr co repo/trunk repo-trunk
  $ cd repo-trunk
  $ echo a > a
  $ bzr add -q a
  $ bzr ci -qm adda
  $ bzr tag trunk-tag
  Created tag trunk-tag.
  $ bzr switch -b branch
  Tree is up to date at revision 1.
  Switched to branch: *repo/branch/ (glob)
  $ sleep 1
  $ echo b > b
  $ bzr add -q b
  $ bzr ci -qm addb
  $ bzr tag branch-tag
  Created tag branch-tag.
  $ bzr switch --force ../repo/trunk
  Updated to revision 1.
  Switched to branch: */repo/trunk/ (glob)
  $ sleep 1
  $ echo a >> a
  $ bzr ci -qm changea
  $ cd ..
  $ hg convert --datesort repo repo-bzr
  initializing destination repo-bzr repository
  scanning source...
  sorting...
  converting...
  2 adda
  1 addb
  0 changea
  updating tags
  $ (cd repo-bzr; glog)
  o  3@default "update tags" files: .hgtags
  |
  o  2@default "changea" files: a
  |
  | o  1@branch "addb" files: b
  |/
  o  0@default "adda" files: a
  

Test tags (converted identifiers are not stable because bzr ones are
not and get incorporated in extra fields).

  $ hg -R repo-bzr tags
  tip                                3:* (glob)
  branch-tag                         1:* (glob)
  trunk-tag                          0:* (glob)

Nested repositories (issue3254)

  $ bzr init-repo -q --no-trees repo/inner
  $ bzr init -q repo/inner/trunk
  $ bzr co repo/inner/trunk inner-trunk
  $ cd inner-trunk
  $ echo b > b
  $ bzr add -q b
  $ bzr ci -qm addb
  $ cd ..
  $ hg convert --datesort repo noinner-bzr
  initializing destination noinner-bzr repository
  scanning source...
  sorting...
  converting...
  2 adda
  1 addb
  0 changea
  updating tags