Don't allow MapMutation.update() calls after the mutation is finished

3 files changed, 10 insertions, 0 deletions

diff --git a/immutables/_map.c b/immutables/_map.c
index 9a81556..9b406ea 100644
--- a/immutables/_map.c
+++ b/immutables/_map.c
@@ -3880,6 +3880,10 @@ mapmut_py_update(MapMutationObject *self, PyObject *args, PyObject *kwds)
         return NULL;
     }
 
+    if (mapmut_check_finalized(self)) {
+        return NULL;
+    }
+
     if (arg != NULL) {
         if (map_update_inplace(self->m_mutid, (BaseMapObject *)self, arg)) {
             return NULL;
diff --git a/immutables/map.py b/immutables/map.py
index 7b230dd..4c5cd49 100644
--- a/immutables/map.py
+++ b/immutables/map.py
@@ -719,6 +719,9 @@ class MapMutation:
             return True
 
     def update(self, col=None, **kw):
+        if self.__mutid == 0:
+            raise ValueError('mutation {!r} has been finished'.format(self))
+
         it = None
         if col is not None:
             if hasattr(col, 'items'):
diff --git a/tests/test_map.py b/tests/test_map.py
index 66d07e7..a99b856 100644
--- a/tests/test_map.py
+++ b/tests/test_map.py
@@ -1148,6 +1148,9 @@ class BaseMapTest:
         with self.assertRaisesRegex(ValueError, 'has been finished'):
             mm['a'] = 'b'
 
+        with self.assertRaisesRegex(ValueError, 'has been finished'):
+            mm.update(a='b')
+
     def test_map_mut_13(self):
         key1 = HashKey(123, 'aaa')
         key2 = HashKey(123, 'aaa')