record: Implement __contains__ (see issue #11)

Author: 1st1

asyncpg/protocol/record/recordobj.c

@@ -469,6 +469,18 @@ record_items(PyObject *o, PyObject *args)
 }
 
 
+static int
+record_contains(ApgRecordObject *o, PyObject *arg)
+{
+    if (!ApgRecord_CheckExact(o)) {
+        PyErr_BadInternalCall();
+        return -1;
+    }
+
+    return PySequence_Contains(o->mapping, arg);
+}
+
+
 static PySequenceMethods record_as_sequence = {
     (lenfunc)record_length,                          /* sq_length */
     0,                                               /* sq_concat */
@@ -477,7 +489,7 @@ static PySequenceMethods record_as_sequence = {
     0,                                               /* sq_slice */
     0,                                               /* sq_ass_item */
     0,                                               /* sq_ass_slice */
-    0,                                               /* sq_contains */
+    (objobjproc)record_contains,                     /* sq_contains */
 };
 
 

tests/test_record.py

@@ -212,6 +212,19 @@ def test_record_hash(self):
         self.assertNotIn(r3, d)
         self.assertIn(r4, d)
 
+    def test_record_contains(self):
+        r = Record(R_AB, (42, 43))
+        self.assertIn('a', r)
+        self.assertIn('b', r)
+        self.assertNotIn('z', r)
+
+        r = Record(None, (42, 43))
+        with self.assertRaises(TypeError):
+            self.assertIn('a', r)
+
+        with self.assertRaises(TypeError):
+            type(r).__contains__(None, 'a')
+
     def test_record_cmp(self):
         AB = collections.namedtuple('AB', ('a', 'b'))