Add unit test for cypclass method resolution order

tests/run/cypclass_mro.pyx

+# mode: run
+# tag: cpp, cpp11, pthread
+# cython: experimental_cpp_class_def=True, language_level=2
+
+cdef cypclass LeftAdd:
+    int __add__(self, int other):
+        return 1
+
+cdef cypclass RightAdd:
+    int __add__(self, int other):
+        return 0
+
+cdef cypclass DerivedAdd(LeftAdd, RightAdd):
+    pass
+
+def test_binop_mro():
+    """
+    >>> test_binop_mro()
+    (1, 1, 1)
+    """
+
+    d = DerivedAdd()
+    cdef int r1 = d + 1
+
+    cdef RightAdd r = DerivedAdd()
+    cdef int r2 = r + 1
+
+    cdef LeftAdd l = DerivedAdd()
+    cdef int r3 = l + 1
+
+    return (r1, r2, r3)
+
+
+cdef cypclass BaseFoo:
+    int foo(self):
+        return 0
+
+cdef cypclass InheritFoo(BaseFoo):
+    pass
+
+cdef cypclass OverrideFoo(BaseFoo):
+    int foo(self):
+        return 1
+
+cdef cypclass MixinFoo(InheritFoo, OverrideFoo):
+    pass
+
+def test_mixin_mro():
+    """
+    >>> test_mixin_mro()
+    (1, 1)
+    """
+
+    m = MixinFoo()
+    cdef int r1 = m.foo()
+
+    cdef InheritFoo i = MixinFoo()
+    cdef int r2 = i.foo()
+
+    return r1, r2
+
+
+cdef cypclass LeftBar:
+    int bar(self):
+        return 1
+
+cdef cypclass RightBar:
+    int bar(self):
+        return 0
+
+cdef cypclass InheritBarTwice(LeftBar, RightBar):
+    pass
+
+def test_unrelated_mro():
+    """
+    >>> test_unrelated_mro()
+    (1, 1, 1)
+    """
+
+    d = InheritBarTwice()
+    cdef int r1 = d.bar()
+
+    cdef RightBar r = InheritBarTwice()
+    cdef int r2 = r.bar()
+
+    cdef LeftBar l = InheritBarTwice()
+    cdef int r3 = l.bar()
+
+    return r1, r2, r3
+
+
+cdef cypclass BaseStaticBaz:
+    @staticmethod
+    int baz():
+        return 0
+
+cdef cypclass InheritStaticBaz(BaseStaticBaz):
+    pass
+
+cdef cypclass OverloadStaticBaz(BaseStaticBaz):
+    @staticmethod
+    int baz():
+        return 1
+
+cdef cypclass MixinStaticBaz(InheritStaticBaz, OverloadStaticBaz):
+    pass
+
+def test_mixin_static_mro():
+    """
+    >>> test_mixin_static_mro()
+    (1, 1)
+    """
+
+    m = MixinStaticBaz()
+    cdef int r1 = m.baz()
+
+    cdef InheritStaticBaz i = MixinStaticBaz()
+    cdef int r2 = i.baz()
+
+    return r1, r2
+
+
+cdef cypclass LeftStaticFoobar:
+    @staticmethod
+    int foobar():
+        return 1
+
+cdef cypclass RightStaticFoobar:
+    @staticmethod
+    int foobar():
+        return 0
+
+cdef cypclass InheritStaticFoobarTwice(LeftStaticFoobar, RightStaticFoobar):
+    pass
+
+def test_unrelated_static_mro():
+    """
+    >>> test_unrelated_static_mro()
+    (1, 1, 1)
+    """
+
+    d = InheritStaticFoobarTwice()
+    cdef int r1 = d.foobar()
+
+    cdef RightStaticFoobar r = InheritStaticFoobarTwice()
+    cdef int r2 = r.foobar()
+
+    cdef LeftStaticFoobar l = InheritStaticFoobarTwice()
+    cdef int r3 = l.foobar()
+
+    return r1, r2, r3
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