Add a prim for 3-argument getattr (mypyc/mypyc#687)

msullivan · web-flow · commit 4c97097fd51e · 2019-08-18T14:05:28.000-07:00
diff --git a/mypyc/lib-rt/CPy.h b/mypyc/lib-rt/CPy.h
@@ -972,6 +972,17 @@ static PyObject *CPy_GetCoro(PyObject *obj)
     }
 }
 
+static PyObject *CPyObject_GetAttr3(PyObject *v, PyObject *name, PyObject *defl)
+{
+    PyObject *result = PyObject_GetAttr(v, name);
+    if (!result && PyErr_ExceptionMatches(PyExc_AttributeError)) {
+        PyErr_Clear();
+        Py_INCREF(defl);
+        result = defl;
+    }
+    return result;
+}
+
 // mypy lets ints silently coerce to floats, so a mypyc runtime float
 // might be an int also
 static inline bool CPyFloat_Check(PyObject *o) {
diff --git a/mypyc/ops_misc.py b/mypyc/ops_misc.py
@@ -273,6 +273,14 @@
     emit=call_emit('PyObject_GetAttr')
 )
 
+func_op(
+    name='builtins.getattr',
+    arg_types=[object_rprimitive, object_rprimitive, object_rprimitive],
+    result_type=object_rprimitive,
+    error_kind=ERR_MAGIC,
+    emit=call_emit('CPyObject_GetAttr3')
+)
+
 py_setattr_op = func_op(
     name='builtins.setattr',
     arg_types=[object_rprimitive, object_rprimitive, object_rprimitive],
