Fix #13 - support slicing.

collections_extended/setlists.py

@@ -144,27 +144,36 @@ class setlist(_basesetlist, MutableSequence, MutableSet):
 	## Implement MutableSequence
 	def __setitem__(self, index, value):
 		if isinstance(index, slice):
-			pass
-		index = self._fix_neg_index(index)
-		old_value = self._list[index]
-		if value in self:
-			if value == old_value:
-				return
+			old_values = self[index]
+			for v in value:
+				if v in self and v not in old_values:
+					raise ValueError
 			else:
-				raise ValueError
-		del self._dict[old_value]
-		self._list[index] = value
-		self._dict[value] = index
+				self._list[index] = value
+				self._dict = {v: i for i, v in enumerate(self._list)}
+		else:
+			index = self._fix_neg_index(index)
+			old_value = self._list[index]
+			if value in self:
+				if value == old_value:
+					return
+				else:
+					raise ValueError
+			del self._dict[old_value]
+			self._list[index] = value
+			self._dict[value] = index
 
 	def __delitem__(self, index):
 		if isinstance(index, slice):
-			pass
-		index = self._fix_neg_index(index)
-		value = self._list[index]
-		del self._dict[value]
-		for elem in self._list[index+1:]:
-			self._dict[elem] -= 1
-		del self._list[index]
+			values_to_remove = self._list[index]
+			self.remove_all(values_to_remove)
+		else:
+			index = self._fix_neg_index(index)
+			value = self._list[index]
+			del self._dict[value]
+			for elem in self._list[index+1:]:
+				self._dict[elem] -= 1
+			del self._list[index]
 
 	def insert(self, index, value):
 		if value in self:

tests/test_setlists.py

@@ -150,21 +150,22 @@ def test_setitem():
 	with pytest.raises(IndexError):
 		sl[10] = 'd'
 	assert sl == setlist(['a'] + list(range(1, 9)) + ['c'])
-	test_set_slice(slice(0, 2), ['a', 'b'])
-	test_set_slice(slice(2, 4), ['a', 'b'])
-	test_set_slice(slice(7, 9), ['a', 'b'])
-	test_set_slice(slice(2, -2), ['a', 'b'])
-	test_set_slice(slice(2, 7, 2), ['a', 'b'])
-	test_set_slice(slice(-1, 0, -1), ['a', 'b'])
-	test_set_slice(slice(-1, 0, -2), ['a', 'b'])
+	compare_set_slice_to_list(slice(0, 2), ['a', 'b'])
+	compare_set_slice_to_list(slice(2, 4), ['a', 'b'])
+	compare_set_slice_to_list(slice(7, 9), ['a', 'b'])
+	compare_set_slice_to_list(slice(2, -2), ['a', 'b'])
+	compare_set_slice_to_list(slice(2, 5, 2), ['a', 'b'])
+	compare_set_slice_to_list(slice(-1, None, -1), list(range(10)))
 	with pytest.raises(TypeError):
 		sl[0:2] = 1
 	sl = setlist(range(10))
 	with pytest.raises(ValueError):
 		sl[0:2] = [8, 9]
+	with pytest.raises(ValueError):
+		sl[-1:0:-2] = ['a', 'b']
 
 
-def test_set_slice(slice_, replacement):
+def compare_set_slice_to_list(slice_, replacement):
 	sl = setlist(range(10))
 	sl[slice_] = replacement
 	l = list(range(10))
@@ -182,14 +183,14 @@ def test_delitem():
 	assert sl == setlist(range(1, 8))
 	with pytest.raises(IndexError):
 		del sl[10]
-	test_del_slice(slice(0, 2))
-	test_del_slice(slice(6, 9))
-	test_del_slice(slice(3, 7))
-	test_del_slice(slice(7, 3, -1))
-	test_del_slice(slice(0, 7, 2))
+	compare_del_slice_to_list(slice(0, 2))
+	compare_del_slice_to_list(slice(6, 9))
+	compare_del_slice_to_list(slice(3, 7))
+	compare_del_slice_to_list(slice(7, 3, -1))
+	compare_del_slice_to_list(slice(0, 7, 2))
 
 
-def test_del_slice(slice_):
+def compare_del_slice_to_list(slice_):
 	sl = setlist(range(10))
 	del sl[slice_]
 	l = list(range(10))