submodule.update: previous_commit is now set according to the stored reflog value, and is not using ORIG_HEAD anymore

Author: Byron

objects/submodule/root.py

@@ -68,19 +68,15 @@ def update(self, previous_commit=None, recursive=True, force_remove=False, init=
 		##################
 		cur_commit = repo.head.commit
 		if previous_commit is None:
-			symref = repo.head.orig_head()
 			try:
-				previous_commit = symref.commit
-			except Exception:
-				pcommits = cur_commit.parents
-				if pcommits:
-					previous_commit = pcommits[0]
-				else:
-					# in this special case, we just diff against ourselve, which
-					# means exactly no change
-					previous_commit = cur_commit
-				# END handle initial commit
-			# END no ORIG_HEAD
+				previous_commit = repo.commit(repo.head.log_entry(-1).oldhexsha)
+				if previous_commit.binsha == previous_commit.NULL_BIN_SHA:
+					raise IndexError
+				#END handle initial commit
+			except IndexError:
+				# in new repositories, there is no previous commit
+				previous_commit = cur_commit
+			#END exception handling
 		else:
 			previous_commit = repo.commit(previous_commit)	 # obtain commit object 
 		# END handle previous commit

test/test_refs.py

@@ -149,6 +149,9 @@ def test_is_valid(self):
 		assert self.rorepo.head.reference.is_valid()
 		assert SymbolicReference(self.rorepo, 'hellothere').is_valid() == False
 
+	def test_orig_head(self):
+		assert type(self.rorepo.head.orig_head()) == SymbolicReference
+		
 	@with_rw_repo('0.1.6')
 	def test_head_reset(self, rw_repo):
 		cur_head = rw_repo.head