def find_common_parent(self, commit_one, commit_two):
"""Find the common parent between the two commits if one exists"""
one = Commit(self)
one.checkout(commit_one)
two = Commit(self)
two.checkout(commit_two)
listone = one.getAncestors()
listtwo = two.getAncestors()
def compare(a, b):
common = None
for index in range(len(a)):
if a[index] is not b[index]:
return common
common = a[index]
return common
if len(listone) < len(listtwo):
common = compare(listone, listtwo)
else:
common = compare(listtwo, listone)
if not common:
raise NoCommonParent("The commits %s and %s do not share a common parent" % (commit_one, commit_two))
return common
