Add mypy tests through ament_mypy

Signed-off-by: Christophe Bedard <bedard.christophe@gmail.com>

tracetools_read/package.xml

@@ -13,6 +13,7 @@
 
   <test_depend>ament_copyright</test_depend>
   <test_depend>ament_flake8</test_depend>
+  <test_depend>ament_mypy</test_depend>
   <test_depend>ament_pep257</test_depend>
   <test_depend>ament_xmllint</test_depend>
   <test_depend>python3-pytest</test_depend>

tracetools_read/test/test_mypy.py

@@ -0,0 +1,22 @@
+# Copyright 2019 Canonical Ltd
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from ament_mypy.main import main
+import pytest
+
+
+@pytest.mark.mypy
+@pytest.mark.linter
+def test_mypy():
+    assert main(argv=[]) == 0, 'Found errors'

tracetools_read/tracetools_read/trace.py

@@ -23,9 +23,6 @@ import babeltrace
 from . import DictEvent
 
 
-BabeltraceEvent = babeltrace.babeltrace.Event
-
-
 def is_trace_directory(path: str) -> bool:
     """
     Check recursively if a path is a trace directory.
@@ -42,7 +39,7 @@ def is_trace_directory(path: str) -> bool:
     return traces is not None and len(traces) > 0
 
 
-def get_trace_ctf_events(trace_directory: str) -> Iterable[BabeltraceEvent]:
+def get_trace_ctf_events(trace_directory: str) -> Iterable[babeltrace.babeltrace.Event]:
     """
     Get the events of a trace.
 
@@ -61,7 +58,10 @@ def get_trace_events(trace_directory: str) -> List[DictEvent]:
     :param trace_directory: the path to the main/top trace directory
     :return: events
     """
-    return [event_to_dict(event) for event in get_trace_ctf_events(trace_directory)]
+    events: List[DictEvent] = [
+        event_to_dict(event) for event in get_trace_ctf_events(trace_directory)
+    ]
+    return events
 
 
 # List of ignored CTF fields
@@ -82,7 +82,7 @@ _IGNORED_FIELDS = [
 _DISCARD = 'events_discarded'
 
 
-def event_to_dict(event: BabeltraceEvent) -> DictEvent:
+def event_to_dict(event: babeltrace.babeltrace.Event) -> DictEvent:
     """
     Convert name, timestamp, and all other keys except those in IGNORED_FIELDS into a dictionary.