push: obsolete rather than rebase & strip when enabled This requires a few changes to wrappers.push() to use obsolescence rather than strip and to make the rebase -- which is non-destructive with obsolete active -- to no longer keep the originals. Possible future work involves no longer relying on rebase for non-outgoing revisions, and simply leaving them in the troubled state. We test this feature by adding setting obsolete_mode_tests to True in classes that push changes.

--- a/tests/test_externals.py
+++ b/tests/test_externals.py
@@ -277,6 +277,8 @@ d3/ext3 = [hgsubversion] d3:^/trunk/comm
         self.test_mergeexternals(True)
 
 class TestPushExternals(test_util.TestBase):
+    obsolete_mode_tests = True
+
     def test_push_externals(self, stupid=False):
         repo = self._load_fixture_and_fetch('pushexternals.svndump')
         # Add a new reference on an existing and non-existing directory