1 files changed, 118 insertions, 0 deletions
diff --git a/tests/functional/u/unexpected_keyword_arg.py b/tests/functional/u/unexpected_keyword_arg.py
new file mode 100644
index 000000000..e7b648899
--- /dev/null
+++ b/tests/functional/u/unexpected_keyword_arg.py
@@ -0,0 +1,118 @@
+"""Tests for unexpected-keyword-arg"""
+# pylint: disable=undefined-variable, too-few-public-methods, missing-function-docstring, missing-class-docstring
+
+
+def non_param_decorator(func):
+    """Decorator without a parameter"""
+
+    def new_func():
+        func()
+
+    return new_func
+
+
+def param_decorator(func):
+    """Decorator with a parameter"""
+
+    def new_func(internal_arg=3):
+        func(junk=internal_arg)
+
+    return new_func
+
+
+def kwargs_decorator(func):
+    """Decorator with kwargs.
+    The if ... else makes the double decoration with param_decorator valid.
+    """
+
+    def new_func(**kwargs):
+        if "internal_arg" in kwargs:
+            func(junk=kwargs["internal_arg"])
+        else:
+            func(junk=kwargs["junk"])
+
+    return new_func
+
+
+@non_param_decorator
+def do_something(junk=None):
+    """A decorated function. This should not be passed a keyword argument"""
+    print(junk)
+
+
+do_something(internal_arg=2)  # [unexpected-keyword-arg]
+
+
+@param_decorator
+def do_something_decorated(junk=None):
+    """A decorated function. This should be passed a keyword argument"""
+    print(junk)
+
+
+do_something_decorated(internal_arg=2)
+
+
+@kwargs_decorator
+def do_something_decorated_too(junk=None):
+    """A decorated function. This should be passed a keyword argument"""
+    print(junk)
+
+
+do_something_decorated_too(internal_arg=2)
+
+
+@non_param_decorator
+@kwargs_decorator
+def do_something_double_decorated(junk=None):
+    """A decorated function. This should not be passed a keyword argument.
+    non_param_decorator will raise an exception if a keyword argument is passed.
+    """
+    print(junk)
+
+
+do_something_double_decorated(internal_arg=2)  # [unexpected-keyword-arg]
+
+
+@param_decorator
+@kwargs_decorator
+def do_something_double_decorated_correct(junk=None):
+    """A decorated function. This should be passed a keyword argument"""
+    print(junk)
+
+
+do_something_double_decorated_correct(internal_arg=2)
+
+
+# Test that we don't crash on Class decoration
+class DecoratorClass:
+    pass
+
+
+@DecoratorClass
+def crash_test():
+    pass
+
+
+crash_test(internal_arg=2)  # [unexpected-keyword-arg]
+
+
+# Test that we don't emit a false positive for uninferable decorators
+@unknown_decorator
+def crash_test_two():
+    pass
+
+
+crash_test_two(internal_arg=2)
+
+
+# Test that we don't crash on decorators that don't return anything
+def no_return_decorator(func):
+    print(func)
+
+
+@no_return_decorator
+def test_no_return():
+    pass
+
+
+test_no_return(internal_arg=2)  # [unexpected-keyword-arg]