Implement setlist.reverse and add tests, fix #125

collections_extended/setlists.py

@@ -432,6 +432,12 @@ def remove_all(self, elems_to_delete):
 		"""
 		self._delete_all(elems_to_delete, raise_errors=True)
 
+	def reverse(self):
+		"""Reverse the setlist in-place."""
+		self._list.reverse()
+		for index, item in enumerate(self._list):
+			self._dict[item] = index
+
 	# Implement MutableSet
 
 	def add(self, item):

tests/test_setlists.py

@@ -596,3 +596,9 @@ def test_swap():
 	sl.swap(-1, 1)
 	assert_internal_structure(sl)
 	assert sl == setlist('afbdec')
+
+
+def test_reverse():
+	sl = setlist('abcdef')
+	sl.reverse()
+	assert sl == setlist('fedcba')