optimize general sorted(x) calls

Cython/Compiler/Optimize.py

@@ -1477,6 +1477,10 @@ class EarlyReplaceBuiltinCalls(Visitor.EnvTransform):
             gen_expr_node.pos, loop = loop_node, result_node = result_ref,
             expr_scope = gen_expr_node.expr_scope, orig_func = is_any and 'any' or 'all')
 
+    PySequence_List_func_type = PyrexTypes.CFuncType(
+        Builtin.list_type,
+        [PyrexTypes.CFuncTypeArg("it", PyrexTypes.py_object_type, None)])
+
     def _handle_simple_function_sorted(self, node, pos_args):
         """Transform sorted(genexpr) and sorted([listcomp]) into
         [listcomp].sort().  CPython just reads the iterable into a
@@ -1514,7 +1518,11 @@ class EarlyReplaceBuiltinCalls(Visitor.EnvTransform):
             expr = pos_args[0].as_list()
             listcomp_node = loop_node = expr
         else:
-            return node
+            # Interestingly, PySequence_List works on a lot of non-sequence
+            # things as well.
+            listcomp_node = loop_node = ExprNodes.PythonCapiCallNode(
+                node.pos, "PySequence_List", self.PySequence_List_func_type,
+                args=pos_args, is_temp=True)
 
         result_node = UtilNodes.ResultRefNode(
             pos = loop_node.pos, type = Builtin.list_type, may_hold_none=False)

tests/run/builtin_sorted.pyx

 cimport cython
 
+def generator():
+    yield 2
+    yield 1
+    yield 3
+
+def returns_set():
+    return set(["foo", "bar", "baz"])
+
+def returns_tuple():
+    return (1, 2, 3, 0)
+
+@cython.test_fail_if_path_exists("//SimpleCallNode")
+def sorted_arg(x):
+    """
+    >>> a = [3, 2, 1]
+    >>> sorted_arg(a)
+    [1, 2, 3]
+    >>> a
+    [3, 2, 1]
+    >>> sorted(generator())
+    [1, 2, 3]
+    >>> sorted(returns_set())
+    ['bar', 'baz', 'foo']
+    >>> sorted(returns_tuple())
+    [0, 1, 2, 3]
+    >>> sorted(object())
+    Traceback (most recent call last):
+    TypeError: 'object' object is not iterable
+    """
+    return sorted(x)
+
 #@cython.test_fail_if_path_exists("//GeneratorExpressionNode",
 #                                 "//ComprehensionNode//NoneCheckNode")
 #@cython.test_assert_path_exists("//ComprehensionNode")
@@ -10,7 +41,7 @@ def sorted_genexp():
     """
     return sorted(i*i for i in range(10,0,-1))
 
-#@cython.test_assert_path_exists("//SimpleCallNode//SimpleCallNode")
+@cython.test_assert_path_exists("//SimpleCallNode//SimpleCallNode")
 def sorted_list_of_range():
     """
     >>> sorted_list_of_range()