optimize: list(ob) -> PySequence_List(ob)

Cython/Compiler/Optimize.py

@@ -2021,6 +2021,20 @@ class OptimizeBuiltinCalls(Visitor.NodeRefCleanupMixin,
                 )
         return node
 
+    PySequence_List_func_type = PyrexTypes.CFuncType(
+        Builtin.list_type,
+        [PyrexTypes.CFuncTypeArg("it", PyrexTypes.py_object_type, None)])
+
+    def _handle_simple_function_list(self, node, function, pos_args):
+        """Turn list(ob) into PySequence_List(ob).
+        """
+        if len(pos_args) != 1:
+            return node
+        arg = pos_args[0]
+        return ExprNodes.PythonCapiCallNode(
+            node.pos, "PySequence_List", self.PySequence_List_func_type,
+            args=pos_args, is_temp=node.is_temp)
+
     PyList_AsTuple_func_type = PyrexTypes.CFuncType(
         Builtin.tuple_type, [
             PyrexTypes.CFuncTypeArg("list", Builtin.list_type, None)

tests/run/list.pyx

@@ -41,6 +41,18 @@ def k(obj1, obj2, obj3, obj4, obj5):
     obj1 = [17, 42, 88]
     return obj1
 
+@cython.test_fail_if_path_exists("//SimpleCallNode")
+def test_list_call(ob):
+    """
+    >>> def f():
+    ...     yield 1
+    ...     yield 2
+    ...
+    >>> list(f())
+    [1, 2]
+    """
+    return list(ob)
+
 def test_list_sort():
     """
     >>> test_list_sort()