[PATCH RFC] obsolete: mark unreachable extinct changesets as hidden

[Pierre-Yves David]

# HG changeset patch
# User Pierre-Yves.David at ens-lyon.org
# Date 1342192006 -7200
# Node ID a08309196cf89676b4f611b7384d1256dc1d7f82
# Parent  de13ccd4ef8d1ed1abc052a57a88b757c17a0594
obsolete: mark unreachable extinct changesets as hidden

The repo.changelog.hiddenrev set is update with all extinct() changeset which
ain't descendants of either:

- the current working copy,
- a bookmark,
- a tag.

It's not really possible to make a lazy filling this set. So we fill it
unconditionally. This will have a noticeable performance impact on simple
operation. I expect the future changelog filtering to allows such lazy
computation.

This changeset focus on a simple implementation of that implement the right
behavior. A better implementation will be necessary before it's made available
to every user.

diff -r de13ccd4ef8d -r a08309196cf8 mercurial/localrepo.py
--- a/mercurial/localrepo.py	Fri Jul 13 14:38:49 2012 +0200
+++ b/mercurial/localrepo.py	Fri Jul 13 17:06:46 2012 +0200
@@ -207,6 +207,29 @@
             p = os.environ['HG_PENDING']
             if p.startswith(self.root):
                 c.readpending('00changelog.i.a')
+        if self.obsstore:
+            ### hide extinct changeset that are not accessible by any mean
+            # XXX Making this for each changelog creation force complex graph
+            # XXX computation this is a bad idea and we should have a more lazy
+            # XXX approach here. But this is ok for a first quick and dirty
+            # XXX version as used in several other place regarding obsstore.
+            # XXX Repo without any obsolete marker won't be impacted
+            hiddenquery = 'extinct() - ::(. + bookmark() + tagged())'
+            # The repo need a changelog to run revset. But don't have any
+            # because this method is meant to provide one. However the
+            # changelog is already fully parsed and ready to use. We temporally
+            # assign it as an attribute to be able to run revset.  Later, more
+            # lazy implementation will probably be called after this step and
+            # won't suffer from this issue
+            self.__dict__['changelog'] = c
+            # Note that the hiddenrevs needs invalidations when
+            # - a new changesets is added (possible unstable above extinct)
+            # - a new obsolete marker is added (possible new extinct changeset)
+            c.hiddenrevs.update(self.revs(hiddenquery))
+            # remove inserted changelog from class attribut to let storecache
+            # do it's jobs
+            if self.__dict__['changelog'] is c:
+                self.__dict__.pop('changelog')
         return c
 
     @storecache('00manifest.i')
diff -r de13ccd4ef8d -r a08309196cf8 tests/test-obsolete.t
--- a/tests/test-obsolete.t	Fri Jul 13 14:38:49 2012 +0200
+++ b/tests/test-obsolete.t	Fri Jul 13 17:06:46 2012 +0200
@@ -76,23 +76,6 @@
   |  date:        Thu Jan 01 00:00:00 1970 +0000
   |  summary:     add new_3_c
   |
-  | x  changeset:   4:ca819180edb9
-  |/   parent:      1:7c3bad9141dc
-  |    user:        test
-  |    date:        Thu Jan 01 00:00:00 1970 +0000
-  |    summary:     add new_2_c
-  |
-  | x  changeset:   3:cdbce2fbb163
-  |/   parent:      1:7c3bad9141dc
-  |    user:        test
-  |    date:        Thu Jan 01 00:00:00 1970 +0000
-  |    summary:     add new_c
-  |
-  | x  changeset:   2:245bde4270cd
-  |/   user:        test
-  |    date:        Thu Jan 01 00:00:00 1970 +0000
-  |    summary:     add original_c
-  |
   o  changeset:   1:7c3bad9141dc
   |  user:        test
   |  date:        Thu Jan 01 00:00:00 1970 +0000
@@ -115,18 +98,6 @@
   |  date:        Thu Jan 01 00:00:00 1970 +0000
   |  summary:     add new_3_c
   |
-  | x  changeset:   4:ca819180edb9
-  |/   parent:      1:7c3bad9141dc
-  |    user:        test
-  |    date:        Thu Jan 01 00:00:00 1970 +0000
-  |    summary:     add new_2_c
-  |
-  | x  changeset:   3:cdbce2fbb163
-  |/   parent:      1:7c3bad9141dc
-  |    user:        test
-  |    date:        Thu Jan 01 00:00:00 1970 +0000
-  |    summary:     add new_c
-  |
   | o  changeset:   2:245bde4270cd
   |/   user:        test
   |    date:        Thu Jan 01 00:00:00 1970 +0000