discovery: add extinct changesets to outgoing.excluded

Before this change, push would incorrectly fast-path the bundle
generation when extinct changesets are involved, because they are not
added to outgoing.excluded. The reason to do so are related to
outgoing.excluded being assumed to contain only secret changesets by
scmutil.nochangesfound(), when displaying warnings like:

 changes found (ignored 9 secret changesets)

Still, outgoing.excluded seems like a good API to report the extinct
changesets instead of dedicated code and nothing in the docstring
indicates it to be bound to secret changesets. This patch adds extinct
changesets to outgoing.excluded and fixes scmutil.nochangesfound() to
filter the excluded node list.

Original version and test by [e-mail]

tests/test-obsolete-changeset-exchange.t

@@ -0,0 +1,48 b''
+Test changesets filtering during exchanges (some tests are still in
+test-obsolete.t)
+
+Push does corrupt remote
+------------------------
+
+Create a DAG where a changeset reuses a revision from a file first used in an
+extinct changeset.
+
+  $ hg init local
+  $ cd local
+  $ echo 'base' > base
+  $ hg commit -Am base
+  adding base
+  $ echo 'A' > A
+  $ hg commit -Am A
+  adding A
+  $ hg up 0
+  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
+  $ hg revert -ar 1
+  adding A
+  $ hg commit -Am "A'"
+  created new head
+  $ hg log -G --template='{desc} {node}'
+  @  A' f89bcc95eba5174b1ccc3e33a82e84c96e8338ee
+  |
+  | o  A 9d73aac1b2ed7d53835eaeec212ed41ea47da53a
+  |/
+  o  base d20a80d4def38df63a4b330b7fb688f3d4cae1e3
+  
+  $ hg debugobsolete 9d73aac1b2ed7d53835eaeec212ed41ea47da53a f89bcc95eba5174b1ccc3e33a82e84c96e8338ee
+
+Push it. The bundle should not refer to the extinct changeset.
+
+  $ hg init ../other
+  $ hg push ../other
+  pushing to ../other
+  searching for changes
+  adding changesets
+  adding manifests
+  adding file changes
+  added 2 changesets with 2 changes to 2 files
+  $ hg -R ../other verify
+  checking changesets
+  checking manifests
+  crosschecking files in changesets and manifests
+  checking files
+  2 files, 2 changesets, 2 total revisions

mercurial/commands.py

@@ -1050,7 +1050,7 b' def bundle(ui, repo, fname, dest=None, *'
                                                 portable=True)
         cg = repo.getlocalbundle('bundle', outgoing)
     if not cg:
-        scmutil.nochangesfound(ui, outgoing and outgoing.excluded)
+        scmutil.nochangesfound(ui, repo, outgoing and outgoing.excluded)
         return 1
 
     changegroup.writebundle(cg, fname, bundletype)

mercurial/discovery.py

@@ -116,7 +116,7 b' def findcommonoutgoing(repo, other, only'
         # use visible heads as it should be cached
         og.missingheads = visibleheads(repo)
         # extinct changesets are silently ignored
-        og.excluded = [ctx.node() for ctx in repo.set('secret()')]
+        og.excluded = [ctx.node() for ctx in repo.set('secret() or extinct()')]
     else:
         # compute common, missing and exclude secret stuff
         sets = repo.changelog.findcommonmissing(og.commonheads, onlyheads)
@@ -125,12 +125,10 b' def findcommonoutgoing(repo, other, only'
         og.excluded = excluded = []
         for node in allmissing:
             ctx = repo[node]
-            if not ctx.extinct():
-                # extinct changesets are silently ignored
-                if ctx.phase() >= phases.secret:
-                    excluded.append(node)
-                else:
-                    missing.append(node)
+            if ctx.phase() >= phases.secret or ctx.extinct():
+                excluded.append(node)
+            else:
+                missing.append(node)
         if len(missing) == len(allmissing):
             missingheads = onlyheads
         else: # update missing heads

mercurial/hg.py

@@ -525,7 +525,7 b' def _outgoing(ui, repo, dest, opts):'
                                             force=opts.get('force'))
     o = outgoing.missing
     if not o:
-        scmutil.nochangesfound(repo.ui, outgoing.excluded)
+        scmutil.nochangesfound(repo.ui, repo, outgoing.excluded)
         return None
     return o
 

mercurial/localrepo.py

@@ -1844,7 +1844,7 b' class localrepository(object):'
 
                 if not outgoing.missing:
                     # nothing to push
-                    scmutil.nochangesfound(self.ui, outgoing.excluded)
+                    scmutil.nochangesfound(self.ui, self, outgoing.excluded)
                     ret = None
                 else:
                     # something to push

mercurial/scmutil.py

@@ -6,12 +6,21 b''
 # GNU General Public License version 2 or any later version.
 
 from i18n import _
-import util, error, osutil, revset, similar, encoding
+import util, error, osutil, revset, similar, encoding, phases
 import match as matchmod
 import os, errno, re, stat, sys, glob
 
-def nochangesfound(ui, secretlist=None):
-    '''report no changes for push/pull'''
+def nochangesfound(ui, repo, excluded=None):
+    '''Report no changes for push/pull, excluded is None or a list of
+    nodes excluded from the push/pull.
+    '''
+    secretlist = []
+    if excluded:
+        for n in excluded:
+            ctx = repo[n]
+            if ctx.phase() >= phases.secret and not ctx.extinct():
+                secretlist.append(n)
+
     if secretlist:
         ui.status(_("no changes found (ignored %d secret changesets)\n")
                   % len(secretlist))