Adding cython v0.20.2 in third-party.

third_party/cython/src/Cython/Compiler/Tests/TestSignatureMatching.py

Index: third_party/cython/src/Cython/Compiler/Tests/TestSignatureMatching.py
diff --git a/third_party/cython/src/Cython/Compiler/Tests/TestSignatureMatching.py b/third_party/cython/src/Cython/Compiler/Tests/TestSignatureMatching.py
new file mode 100644
index 0000000000000000000000000000000000000000..8410ec593b9cc36714a46d3fa49a36024ab3dbd3
--- /dev/null
+++ b/third_party/cython/src/Cython/Compiler/Tests/TestSignatureMatching.py
@@ -0,0 +1,74 @@
+import unittest
+
+from Cython.Compiler import PyrexTypes as pt
+from Cython.Compiler.ExprNodes import NameNode
+from Cython.Compiler.PyrexTypes import CFuncTypeArg
+
+def cfunctype(*arg_types):
+    return pt.CFuncType(pt.c_int_type,
+        [ CFuncTypeArg("name", arg_type, None) for arg_type in arg_types ])
+
+def cppclasstype(name, base_classes):
+    return pt.CppClassType(name, None, 'CPP_'+name, base_classes)
+
+class SignatureMatcherTest(unittest.TestCase):
+    """
+    Test the signature matching algorithm for overloaded signatures.
+    """
+    def assertMatches(self, expected_type, arg_types, functions):
+        args = [ NameNode(None, type=arg_type) for arg_type in arg_types ]
+        match = pt.best_match(args, functions)
+        if expected_type is not None:
+            self.assertNotEqual(None, match)
+        self.assertEqual(expected_type, match.type)
+
+    def test_cpp_reference_single_arg(self):
+        function_types = [
+            cfunctype(pt.CReferenceType(pt.c_int_type)),
+            cfunctype(pt.CReferenceType(pt.c_long_type)),
+            cfunctype(pt.CReferenceType(pt.c_double_type)),
+            ]
+
+        functions = [ NameNode(None, type=t) for t in function_types ]
+        self.assertMatches(function_types[0], [pt.c_int_type], functions)
+        self.assertMatches(function_types[1], [pt.c_long_type], functions)
+        self.assertMatches(function_types[2], [pt.c_double_type], functions)
+
+    def test_cpp_reference_two_args(self):
+        function_types = [
+            cfunctype(
+                pt.CReferenceType(pt.c_int_type), pt.CReferenceType(pt.c_long_type)),
+            cfunctype(
+                pt.CReferenceType(pt.c_long_type), pt.CReferenceType(pt.c_long_type)),
+            ]
+
+        functions = [ NameNode(None, type=t) for t in function_types ]
+        self.assertMatches(function_types[0], [pt.c_int_type, pt.c_long_type], functions)
+        self.assertMatches(function_types[1], [pt.c_long_type, pt.c_long_type], functions)
+        self.assertMatches(function_types[1], [pt.c_long_type, pt.c_int_type], functions)
+
+    def test_cpp_reference_cpp_class(self):
+        classes = [ cppclasstype("Test%d"%i, []) for i in range(2) ]
+        function_types = [
+            cfunctype(pt.CReferenceType(classes[0])),
+            cfunctype(pt.CReferenceType(classes[1])),
+            ]
+
+        functions = [ NameNode(None, type=t) for t in function_types ]
+        self.assertMatches(function_types[0], [classes[0]], functions)
+        self.assertMatches(function_types[1], [classes[1]], functions)
+
+    def test_cpp_reference_cpp_class_and_int(self):
+        classes = [ cppclasstype("Test%d"%i, []) for i in range(2) ]
+        function_types = [
+            cfunctype(pt.CReferenceType(classes[0]), pt.c_int_type),
+            cfunctype(pt.CReferenceType(classes[0]), pt.c_long_type),
+            cfunctype(pt.CReferenceType(classes[1]), pt.c_int_type),
+            cfunctype(pt.CReferenceType(classes[1]), pt.c_long_type),
+            ]
+
+        functions = [ NameNode(None, type=t) for t in function_types ]
+        self.assertMatches(function_types[0], [classes[0], pt.c_int_type], functions)
+        self.assertMatches(function_types[1], [classes[0], pt.c_long_type], functions)
+        self.assertMatches(function_types[2], [classes[1], pt.c_int_type], functions)
+        self.assertMatches(function_types[3], [classes[1], pt.c_long_type], functions)