tests/test-convert-svn-encoding.t

obsolete: order of magnitude speedup in _computebumpedset

Reminder: a changeset is said "bumped" if it tries to obsolete a immutable
          changeset.


The previous algorithm for computing bumped changeset was:

    1) Get all public changesets
    2) Find all they successors
    3) Search for stuff that are eligible for being "bumped"
       (mutable and non obsolete)

The entry size of this algorithm is `O(len(public))` which is mostly the same as
`O(len(repo))`. Even this this approach mean fewer obsolescence marker are
traveled, this is not very scalable.

The new algorithm is:

    1) For each potential bumped changesets (non obsolete mutable)
    2) iterate over precursors
    3) if a precursors is public. changeset is bumped

We travel more obsolescence marker, but the entry size is much smaller since
the amount of potential bumped should remains mostly stable with time `O(1)`.

On some confidential gigantic repo this move bumped computation from 15.19s to
0.46s (×33 speedup…). On "smaller" repo (mercurial, cubicweb's review) no
significant gain were seen. The additional traversal of obsolescence marker is
probably probably counter balance the advantage of it.

Other optimisation could be done in the future (eg: sharing precursors cache
for divergence detection)

  $ "$TESTDIR/hghave" svn svn-bindings || exit 80

  $ cat >> $HGRCPATH <<EOF
  > [extensions]
  > convert =
  > EOF

  $ svnadmin create svn-repo
  $ svnadmin load -q svn-repo < "$TESTDIR/svn/encoding.svndump"

Convert while testing all possible outputs

  $ hg --debug convert svn-repo A-hg
  initializing destination A-hg repository
  reparent to file://*/svn-repo (glob)
  run hg sink pre-conversion action
  scanning source...
  found trunk at 'trunk'
  found tags at 'tags'
  found branches at 'branches'
  found branch branch\xc3\xa9 at 5 (esc)
  found branch branch\xc3\xa9e at 6 (esc)
  scanning: 1 revisions
  reparent to file://*/svn-repo/trunk (glob)
  fetching revision log for "/trunk" from 4 to 0
  parsing revision 4 (2 changes)
  parsing revision 3 (4 changes)
  parsing revision 2 (3 changes)
  parsing revision 1 (3 changes)
  no copyfrom path, don't know what to do.
  '/branches' is not under '/trunk', ignoring
  '/tags' is not under '/trunk', ignoring
  scanning: 2 revisions
  reparent to file://*/svn-repo/branches/branch%C3%A9 (glob)
  fetching revision log for "/branches/branch\xc3\xa9" from 5 to 0 (esc)
  parsing revision 5 (1 changes)
  reparent to file://*/svn-repo (glob)
  reparent to file://*/svn-repo/branches/branch%C3%A9 (glob)
  found parent of branch /branches/branch\xc3\xa9 at 4: /trunk (esc)
  scanning: 3 revisions
  reparent to file://*/svn-repo/branches/branch%C3%A9e (glob)
  fetching revision log for "/branches/branch\xc3\xa9e" from 6 to 0 (esc)
  parsing revision 6 (1 changes)
  reparent to file://*/svn-repo (glob)
  reparent to file://*/svn-repo/branches/branch%C3%A9e (glob)
  found parent of branch /branches/branch\xc3\xa9e at 5: /branches/branch\xc3\xa9 (esc)
  scanning: 4 revisions
  scanning: 5 revisions
  scanning: 6 revisions
  sorting...
  converting...
  5 init projA
  source: svn:afeb9c47-92ff-4c0c-9f72-e1f6eb8ac9af/trunk@1
  converting: 0/6 revisions (0.00%)
  4 hello
  source: svn:afeb9c47-92ff-4c0c-9f72-e1f6eb8ac9af/trunk@2
  converting: 1/6 revisions (16.67%)
  reparent to file://*/svn-repo/trunk (glob)
  scanning paths: /trunk/\xc3\xa0 0/3 (0.00%) (esc)
  scanning paths: /trunk/\xc3\xa0/e\xcc\x81 1/3 (33.33%) (esc)
  scanning paths: /trunk/\xc3\xa9 2/3 (66.67%) (esc)
  \xc3\xa0/e\xcc\x81 (esc)
  getting files: \xc3\xa0/e\xcc\x81 1/2 (50.00%) (esc)
  \xc3\xa9 (esc)
  getting files: \xc3\xa9 2/2 (100.00%) (esc)
  3 copy files
  source: svn:afeb9c47-92ff-4c0c-9f72-e1f6eb8ac9af/trunk@3
  converting: 2/6 revisions (33.33%)
  scanning paths: /trunk/\xc3\xa0 0/4 (0.00%) (esc)
  gone from -1
  reparent to file://*/svn-repo (glob)
  reparent to file://*/svn-repo/trunk (glob)
  scanning paths: /trunk/\xc3\xa8 1/4 (25.00%) (esc)
  copied to \xc3\xa8 from \xc3\xa9@2 (esc)
  scanning paths: /trunk/\xc3\xa9 2/4 (50.00%) (esc)
  gone from -1
  reparent to file://*/svn-repo (glob)
  reparent to file://*/svn-repo/trunk (glob)
  scanning paths: /trunk/\xc3\xb9 3/4 (75.00%) (esc)
  mark /trunk/\xc3\xb9 came from \xc3\xa0:2 (esc)
  \xc3\xa0/e\xcc\x81 (esc)
  getting files: \xc3\xa0/e\xcc\x81 1/4 (25.00%) (esc)
  \xc3\xa8 (esc)
  getting files: \xc3\xa8 2/4 (50.00%) (esc)
   \xc3\xa8: copy \xc3\xa9:6b67ccefd5ce6de77e7ead4f5292843a0255329f (esc)
  \xc3\xa9 (esc)
  getting files: \xc3\xa9 3/4 (75.00%) (esc)
  \xc3\xb9/e\xcc\x81 (esc)
  getting files: \xc3\xb9/e\xcc\x81 4/4 (100.00%) (esc)
   \xc3\xb9/e\xcc\x81: copy \xc3\xa0/e\xcc\x81:a9092a3d84a37b9993b5c73576f6de29b7ea50f6 (esc)
  2 remove files
  source: svn:afeb9c47-92ff-4c0c-9f72-e1f6eb8ac9af/trunk@4
  converting: 3/6 revisions (50.00%)
  scanning paths: /trunk/\xc3\xa8 0/2 (0.00%) (esc)
  gone from -1
  reparent to file://*/svn-repo (glob)
  reparent to file://*/svn-repo/trunk (glob)
  scanning paths: /trunk/\xc3\xb9 1/2 (50.00%) (esc)
  gone from -1
  reparent to file://*/svn-repo (glob)
  reparent to file://*/svn-repo/trunk (glob)
  \xc3\xa8 (esc)
  getting files: \xc3\xa8 1/2 (50.00%) (esc)
  \xc3\xb9/e\xcc\x81 (esc)
  getting files: \xc3\xb9/e\xcc\x81 2/2 (100.00%) (esc)
  1 branch to branch?
  source: svn:afeb9c47-92ff-4c0c-9f72-e1f6eb8ac9af/branches/branch?@5
  converting: 4/6 revisions (66.67%)
  reparent to file://*/svn-repo/branches/branch%C3%A9 (glob)
  scanning paths: /branches/branch\xc3\xa9 0/1 (0.00%) (esc)
  0 branch to branch?e
  source: svn:afeb9c47-92ff-4c0c-9f72-e1f6eb8ac9af/branches/branch?e@6
  converting: 5/6 revisions (83.33%)
  reparent to file://*/svn-repo/branches/branch%C3%A9e (glob)
  scanning paths: /branches/branch\xc3\xa9e 0/1 (0.00%) (esc)
  reparent to file://*/svn-repo (glob)
  reparent to file://*/svn-repo/branches/branch%C3%A9e (glob)
  reparent to file://*/svn-repo (glob)
  reparent to file://*/svn-repo/branches/branch%C3%A9e (glob)
  updating tags
  .hgtags
  run hg sink post-conversion action
  $ cd A-hg
  $ hg up
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

Check tags are in UTF-8

  $ cat .hgtags
  e94e4422020e715add80525e8f0f46c9968689f1 branch\xc3\xa9e (esc)
  f7e66f98380ed1e53a797c5c7a7a2616a7ab377d branch\xc3\xa9 (esc)

  $ cd ..