def test_docstring(): def one(x, y): """ Docstring number one """ return x + y def two(x, y): """ Docstring number two """ return x + y def three(x, y): return x + y master_doc = 'Doc of the multimethod itself' f = Dispatcher('f', doc=master_doc) f.add((object, object), one) f.add((int, int), two) f.add((float, float), three) assert one.__doc__.strip() in f.__doc__ assert two.__doc__.strip() in f.__doc__ assert f.__doc__.find(one.__doc__.strip()) < \ f.__doc__.find(two.__doc__.strip()) assert 'object, object' in f.__doc__ assert master_doc in f.__doc__
def test_dispatch_method(): f = Dispatcher('f') @f.register(list) def rev(x): return x[::-1] @f.register(int, int) def add(x, y): return x + y class MyList(list): pass assert f.dispatch(list) is rev assert f.dispatch(MyList) is rev assert f.dispatch(int, int) is add
def test_not_implemented_error(): f = Dispatcher('f') @f.register(float) def _(a): raise MDNotImplementedError() assert raises(NotImplementedError, lambda: f(1.0))
def test_dispatcher(): f = Dispatcher('f') f.add((int, ), inc) f.add((float, ), dec) assert f.resolve((int, )) == inc assert f.dispatch(int) is inc assert f(1) == 2 assert f(1.0) == 0.0
def test_dispatcher(): f = Dispatcher('f') f.add((int,), inc) f.add((float,), dec) assert f.resolve((int,)) == inc assert f.dispatch(int) is inc assert f(1) == 2 assert f(1.0) == 0.0
def test_serializable(): f = Dispatcher('f') f.add((int, ), inc) f.add((float, ), dec) f.add((object, ), identity) import pickle assert isinstance(pickle.dumps(f), (str, bytes)) g = pickle.loads(pickle.dumps(f)) assert g(1) == 2 assert g(1.0) == 0.0 assert g('hello') == 'hello'
def test_help(): def one(x, y): """ Docstring number one """ return x + y def two(x, y): """ Docstring number two """ return x + y def three(x, y): """ Docstring number three """ return x + y master_doc = 'Doc of the multimethod itself' f = Dispatcher('f', doc=master_doc) f.add((object, object), one) f.add((int, int), two) f.add((float, float), three) assert f._help(1, 1) == two.__doc__ assert f._help(1.0, 2.0) == three.__doc__
def test_dispatcher_as_decorator(): f = Dispatcher('f') @f.register(int) def inc(x): return x + 1 @f.register(float) def inc(x): return x - 1 assert f(1) == 2 assert f(1.0) == 0.0
def test_register_stacking(): f = Dispatcher('f') @f.register(list) @f.register(tuple) def rev(x): return x[::-1] assert f((1, 2, 3)) == (3, 2, 1) assert f([1, 2, 3]) == [3, 2, 1] assert raises(NotImplementedError, lambda: f('hello')) assert rev('hello') == 'olleh'
def test_halt_method_resolution(): g = [0] def on_ambiguity(a, b): g[0] += 1 f = Dispatcher('f') halt_ordering() def func(*args): pass f.add((int, object), func) f.add((object, int), func) assert g == [0] restart_ordering(on_ambiguity=on_ambiguity) assert g == [1] print(list(f.ordering)) assert set(f.ordering) == set([(int, object), (object, int)])
def test_on_ambiguity(): f = Dispatcher('f') identity = lambda x: x ambiguities = [False] def on_ambiguity(dispatcher, amb): ambiguities[0] = True f.add((object, object), identity, on_ambiguity=on_ambiguity) assert not ambiguities[0] f.add((object, float), identity, on_ambiguity=on_ambiguity) assert not ambiguities[0] f.add((float, object), identity, on_ambiguity=on_ambiguity) assert ambiguities[0]
def test_source(): def one(x, y): """ Docstring number one """ return x + y def two(x, y): """ Docstring number two """ return x - y master_doc = 'Doc of the multimethod itself' f = Dispatcher('f', doc=master_doc) f.add((int, int), one) f.add((float, float), two) assert 'x + y' in f._source(1, 1) assert 'x - y' in f._source(1.0, 1.0)
def test_serializable(): f = Dispatcher('f') f.add((int,), inc) f.add((float,), dec) f.add((object,), identity) import pickle assert isinstance(pickle.dumps(f), (str, bytes)) g = pickle.loads(pickle.dumps(f)) assert g(1) == 2 assert g(1.0) == 0.0 assert g('hello') == 'hello'
def test_not_implemented(): f = Dispatcher('f') @f.register(object) def _(x): return 'default' @f.register(int) def _(x): if x % 2 == 0: return 'even' else: raise MDNotImplementedError() assert f('hello') == 'default' # default behavior assert f(2) == 'even' # specialized behavior assert f(3) == 'default' # fall bac to default behavior assert raises(NotImplementedError, lambda: f(1, 2))
def test_union_types(): f = Dispatcher('f') f.register((int, float))(inc) assert f(1) == 2 assert f(1.0) == 2.0
def test_source_raises_on_missing_function(): f = Dispatcher('f') assert raises(TypeError, lambda: f.source(1))
def test_raise_error_on_non_class(): f = Dispatcher('f') assert raises(TypeError, lambda: f.add((1, ), inc))
def test_raise_error_on_non_class(): f = Dispatcher('f') assert raises(TypeError, lambda: f.add((1,), inc))
def test_no_implementations(): f = Dispatcher('f') assert raises(NotImplementedError, lambda: f('hello'))