Added test for the new needs_binding method

Author: Sylvain MARIE

pytest_cases/tests/cases/others/test_bound_methods.py

@@ -0,0 +1,134 @@
+import sys
+from functools import partial
+
+import pytest
+
+from pytest_cases.common_others import needs_binding
+
+
+def a(foo, bar=None):
+    return foo * 2
+
+
+b = partial(a, bar=1)
+
+
+def c():
+    def _c(foo):
+        return foo * 2
+    return _c
+
+
+def d():
+    def _d(foo, bar=None):
+        return foo * 2
+    return partial(_d, bar=1)
+
+
+class Foo(object):
+
+    def a(self, foo):
+        assert isinstance(self, Foo)
+        return foo * 2
+
+    @staticmethod
+    def b(foo):
+        return foo * 2
+
+    @classmethod
+    def c(cls, foo):
+        assert issubclass(cls, Foo)
+        return foo * 2
+
+    class MyDesc(object):
+        def __get__(self, instance, owner):
+            def descriptor_method(foo):
+                return foo * 2
+            return descriptor_method
+
+    d = MyDesc()
+
+    def e(self):
+        def nested(foo):
+            return foo * 2
+
+        return nested
+
+    class Nested(object):
+        def a(self, foo):
+            assert isinstance(self, Foo.Nested)
+            return foo * 2
+
+        @staticmethod
+        def b(foo):
+            return foo * 2
+
+        @classmethod
+        def c(cls, foo):
+            assert issubclass(cls, Foo.Nested)
+            return foo * 2
+
+        class MyDesc(object):
+            def __get__(self, instance, owner=None):
+                def descriptor_method(foo):
+                    return foo * 2
+
+                return descriptor_method
+
+        d = MyDesc()
+
+        def e(self):
+            def nested(foo):
+                return foo * 2
+
+            return nested
+
+
+ALL_PY = True
+PY3_ONLY = sys.version_info >= (3,)
+
+
+@pytest.mark.parametrize("name, m, expected, supported", [
+    ("plain_py_func", a, False, ALL_PY),
+    ("partial_func", b, False, ALL_PY),
+    ("nested_func", c(), False, ALL_PY),
+    ("nested_partial_func", d(), False, ALL_PY),
+    # --- class
+    ("method_on_instance", Foo().a, False, ALL_PY),
+    ("method_unbound", Foo.a, True, ALL_PY),
+    ("method_on_class_dict", Foo.__dict__['a'], True, PY3_ONLY),
+    ("static_method_on_instance", Foo().b, False, ALL_PY),
+    ("static_method_on_class", Foo.b, False, ALL_PY),
+    ("static_method_on_class_dict", Foo.__dict__['b'], True, ALL_PY),
+    ("class_method_on_instance", Foo().c, False, ALL_PY),
+    ("class_method_on_class", Foo.c, False, ALL_PY),
+    ("class_method_on_class_dict", Foo.__dict__['c'], True, PY3_ONLY),
+    ("descriptor_method_on_instance", Foo().d, False, ALL_PY),
+    ("descriptor_method_on_class", Foo.d, False, ALL_PY),
+    # --- nested class
+    ("cls_nested_py_func", Foo.Nested().e(), False, ALL_PY),
+    ("cls_nested_method_on_instance", Foo.Nested().a, False, ALL_PY),
+    ("cls_nested_method_unbound", Foo.Nested.a, True, ALL_PY),
+    ("cls_nested_method_on_class_dict", Foo.Nested.__dict__['a'], True, PY3_ONLY),
+    ("cls_nested_static_method_on_instance", Foo.Nested().b, False, ALL_PY),
+    ("cls_nested_static_method_on_class", Foo.Nested.b, False, ALL_PY),
+    ("cls_nested_static_method_on_class_dict", Foo.Nested.__dict__['b'], True, ALL_PY),
+    ("cls_nested_class_method_on_instance", Foo.Nested().c, False, ALL_PY),
+    ("cls_nested_class_method_on_class", Foo.Nested.c, False, ALL_PY),
+    ("cls_nested_class_method_on_class_dict", Foo.Nested.__dict__['c'], True, PY3_ONLY),
+    ("cls_nested_descriptor_method_on_instance", Foo.Nested().d, False, ALL_PY),
+    ("cls_nested_descriptor_method_on_class", Foo.Nested.d, False, ALL_PY),
+], ids=lambda x: str(x) if isinstance(x, (str, bytes, bool)) else "")
+def test_needs_binding(name, m, expected, supported):
+
+    if not supported:
+        pytest.skip("Not supported on this version of python")
+
+    should_bind = needs_binding(m)
+    assert should_bind is expected
+
+    should_bind2, m = needs_binding(m, return_bound=True)
+    assert should_bind == should_bind2
+
+    # test the method
+    assert m(2) == 4