[launch_testing] remove deprecated ready_fn feature

launch_testing/README.md

@@ -44,21 +44,6 @@ The launch description needs to include a `ReadyToTest` action to signal to the
 
 In the above example, there is no need to delay the start of the tests so the `ReadyToTest` action is a peer to the process under test and will signal to the framework that it's safe to start around the same time the `ExecuteProcess` action is run.
 
-In older style tests, a function called `ready_fn` is declared as an argument to `generate_test_description` and must be plumbed into the launch description with an `OpaqueFunction`.
-
-```python
-def generate_test_description(ready_fn):
-
-    return launch.LaunchDescription([
-        launch.actions.ExecuteProcess(
-            cmd=[path_to_process],
-        ),
-
-        # Start tests right away - no need to wait for anything in this example
-        launch.actions.OpaqueFunction(function=lambda context: ready_fn()),
-    ])
-```
-
 #### Active Tests
 
 Any classes that inherit from `unittest.TestCase` and not decorated with the `post_shutdown_test` descriptor will be run concurrently with the proccess under test.

launch_testing/launch_testing/loader.py

@@ -42,49 +42,34 @@ def normalize(result):
             return result, {}
 
     def wrapper(**kwargs):
-
-        fn_args = inspect.getfullargspec(launch_description_fn)
-
-        if 'ready_fn' in fn_args.args + fn_args.kwonlyargs:
-            # This is an old-style launch_description function which expects ready_fn to be passed
-            # in to the function
-            # This type of launch description will be deprecated in the future.  Warn about it
-            # here
-            warnings.warn(
-                'Passing ready_fn as an argument to generate_test_description will '
-                'be removed in a future release.  Include a launch_testing.actions.ReadyToTest '
-                'action in the LaunchDescription instead.'
-            )
-            return normalize(launch_description_fn(**kwargs))
-        else:
-            # This is a new-style launch_description which should contain a ReadyToTest action
-            ready_fn = kwargs.pop('ready_fn')
-            result = normalize(launch_description_fn(**kwargs))
-            # Fish the ReadyToTest action out of the launch description and plumb our
-            # ready_fn to it
-
-            def iterate_ready_to_test_actions(entities):
-                """Recursively search LaunchDescription entities for all ReadyToTest actions."""
-                for entity in entities:
-                    if isinstance(entity, ReadyToTest):
-                        yield entity
+        # This is a new-style launch_description which should contain a ReadyToTest action
+        ready_fn = kwargs.pop('ready_fn')
+        result = normalize(launch_description_fn(**kwargs))
+        # Fish the ReadyToTest action out of the launch description and plumb our
+        # ready_fn to it
+
+        def iterate_ready_to_test_actions(entities):
+            """Recursively search LaunchDescription entities for all ReadyToTest actions."""
+            for entity in entities:
+                if isinstance(entity, ReadyToTest):
+                    yield entity
+                yield from iterate_ready_to_test_actions(
+                    entity.describe_sub_entities()
+                )
+                for conditional_sub_entity in entity.describe_conditional_sub_entities():
                     yield from iterate_ready_to_test_actions(
-                        entity.describe_sub_entities()
+                        conditional_sub_entity[1]
                     )
-                    for conditional_sub_entity in entity.describe_conditional_sub_entities():
-                        yield from iterate_ready_to_test_actions(
-                            conditional_sub_entity[1]
-                        )
-
-            try:
-                ready_action = next(e for e in iterate_ready_to_test_actions(result[0].entities))
-            except StopIteration:  # No ReadyToTest action found
-                raise Exception(
-                    'generate_test_description functions without a ready_fn argument must return '
-                    'a LaunchDescription containing a ReadyToTest action'
-                )
-            ready_action._add_callback(ready_fn)
-            return result
+
+        try:
+            ready_action = next(e for e in iterate_ready_to_test_actions(result[0].entities))
+        except StopIteration:  # No ReadyToTest action found
+            raise Exception(
+                'generate_test_description functions must return '
+                'a LaunchDescription containing a ReadyToTest action'
+            )
+        ready_action._add_callback(ready_fn)
+        return result
 
     return wrapper
 

launch_testing/launch_testing/test_runner.py

@@ -292,8 +292,6 @@ def validate(self):
 
             # Check for extra args in generate_test_description
             for argname in base_args:
-                if argname == 'ready_fn':
-                    continue
                 if argname not in run.param_args.keys():
                     raise Exception(
                         "generate_test_description has unexpected extra argument '{}'".format(

launch_testing/test/launch_testing/test_launch_test_runner_validation.py

@@ -34,9 +34,6 @@ class TestLaunchTestRunnerValidation(unittest.TestCase):
 
     def test_catches_bad_signature(self):
 
-        # A `generate_test_description` function without a ready_fn argument is allowed because
-        # it might be a new style function that uses a ReadyToTest action to signal when it's time
-        # for tests to start.
         # If there's no ReadyToTest action, we won't catch that until later because dut.validate()
         # doesn't actually invoke the function.
         # We will still expect to reject functions with wrong name arguments
@@ -50,18 +47,10 @@ def test_catches_bad_signature(self):
         with self.assertRaisesRegex(Exception, "unexpected extra argument 'misspelled_ready_fn'"):
             dut.validate()
 
-        dut = LaunchTestRunner(
-            make_test_run_for_dut(
-                lambda ready_fn: None
-            )
-        )
-
-        dut.validate()
-
     def test_too_many_arguments(self):
 
         dut = LaunchTestRunner(
-            make_test_run_for_dut(lambda ready_fn, extra_arg: None)
+            make_test_run_for_dut(lambda extra_arg: None)
         )
 
         with self.assertRaisesRegex(Exception, "unexpected extra argument 'extra_arg'"):
@@ -70,7 +59,7 @@ def test_too_many_arguments(self):
     def test_bad_parametrization_argument(self):
 
         @launch_testing.parametrize('bad_argument', [1, 2, 3])
-        def bad_launch_description(ready_fn):
+        def bad_launch_description():
             pass  # pragma: no cover
 
         dut = LaunchTestRunner(