added some tests for the function signature override matcher

Cython/Compiler/Tests/TestSignatureMatching.py

+import unittest
+
+from Cython.Compiler import PyrexTypes as pt
+from Cython.Compiler.ExprNodes import NameNode
+from Cython.Compiler.PyrexTypes import CFuncTypeArg
+
+class SignatureMatcherTest(unittest.TestCase):
+    """
+    Test the signature matching algorithm for overloaded signatures.
+    """
+    def _cfunctype(self, return_type, *arg_types):
+        return pt.CFuncType(return_type,
+            [ CFuncTypeArg("name", arg_type, None) for arg_type in arg_types ])
+
+    def _cppclasstype(self, name, base_classes):
+        return pt.CppClassType(name, None, 'CPP_'+name, base_classes)
+
+    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 = [
+            self._cfunctype(pt.c_int_type,    pt.CReferenceType(pt.c_int_type)),
+            self._cfunctype(pt.c_long_type,   pt.CReferenceType(pt.c_long_type)),
+            self._cfunctype(pt.c_double_type, 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 = [
+            self._cfunctype(
+                pt.c_int_type,
+                pt.CReferenceType(pt.c_int_type), pt.CReferenceType(pt.c_long_type)),
+            self._cfunctype(
+                pt.c_int_type,
+                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 = [ self._cppclasstype("Test%d"%i, []) for i in range(2) ]
+        function_types = [
+            self._cfunctype(pt.c_int_type, pt.CReferenceType(classes[0])),
+            self._cfunctype(pt.c_int_type, 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 = [ self._cppclasstype("Test%d"%i, []) for i in range(2) ]
+        function_types = [
+            self._cfunctype(pt.c_int_type,
+                            pt.CReferenceType(classes[0]), pt.c_int_type),
+            self._cfunctype(pt.c_int_type,
+                            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[1], pt.c_int_type], functions)