Add mypy tests through ament_mypy

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

tracetools_trace/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_trace/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_trace/tracetools_trace/tools/args.py

@@ -31,14 +31,14 @@ class DefaultArgValueCompleter:
         return self.list
 
 
-def parse_args():
+def parse_args() -> argparse.Namespace:
     """Parse args for tracing."""
     parser = argparse.ArgumentParser(description='Setup and launch an LTTng tracing session.')
     add_arguments(parser)
     return parser.parse_args()
 
 
-def add_arguments(parser: argparse.ArgumentParser):
+def add_arguments(parser: argparse.ArgumentParser) -> None:
     parser.add_argument(
         '-s', '--session-name', dest='session_name',
         default=path.append_timestamp('session'),
@@ -47,27 +47,27 @@ def add_arguments(parser: argparse.ArgumentParser):
         '-p', '--path', dest='path',
         default=path.DEFAULT_BASE_PATH,
         help='path of the base directory for trace data (default: %(default)s)')
-    arg = parser.add_argument(
+    events_ust_arg = parser.add_argument(  # type: ignore
         '-u', '--ust', nargs='*', dest='events_ust',
         default=names.DEFAULT_EVENTS_ROS,
         help='the ROS UST events to enable (default: see tracetools_trace.tools.names) '
              '[to disable all UST events, '
              'provide this flag without any event name]')
-    arg.completer = DefaultArgValueCompleter(arg)
-    arg = parser.add_argument(
+    events_ust_arg.completer = DefaultArgValueCompleter(events_ust_arg)  # type: ignore
+    events_kernel_arg = parser.add_argument(  # type: ignore
         '-k', '--kernel', nargs='*', dest='events_kernel',
         default=names.DEFAULT_EVENTS_KERNEL,
         help='the kernel events to enable (default: see tracetools_trace.tools.names) '
              '[to disable all kernel events, '
              'provide this flag without any event name]')
-    arg.completer = DefaultArgValueCompleter(arg)
-    arg = parser.add_argument(
+    events_kernel_arg.completer = DefaultArgValueCompleter(events_kernel_arg)  # type: ignore
+    context_arg = parser.add_argument(  # type: ignore
         '-c', '--context', nargs='*', dest='context_names',
         default=names.DEFAULT_CONTEXT,
         help='the context names to enable (default: see tracetools_trace.tools.names) '
              '[to disable all context names, '
              'provide this flag without any name]')
-    arg.completer = DefaultArgValueCompleter(arg)
+    context_arg.completer = DefaultArgValueCompleter(context_arg)  # type: ignore
     parser.add_argument(
         '-l', '--list', dest='list', action='store_true',
         help='display lists of enabled events and context names (default: %(default)s)')

tracetools_trace/tracetools_trace/tools/lttng.py

@@ -22,7 +22,7 @@ from typing import Optional
 try:
     from . import lttng_impl
 
-    _lttng = lttng_impl
+    _lttng = lttng_impl  # type: ignore
 
     # Check lttng module version
     from distutils.version import StrictVersion
@@ -37,7 +37,7 @@ except ImportError:
     # Fall back on stub functions so that this still passes linter checks
     from . import lttng_stub
 
-    _lttng = lttng_stub
+    _lttng = lttng_stub  # type: ignore
 
 from .names import DEFAULT_CONTEXT
 from .names import DEFAULT_EVENTS_KERNEL

tracetools_trace/tracetools_trace/tools/lttng_impl.py

@@ -41,7 +41,7 @@ def get_version() -> Union[StrictVersion, None]:
     :return: the version as a StrictVersion object, or `None` if it cannot be extracted
     """
     doc_lines = lttng.__doc__.split('\n')
-    first_line = list(filter(None, doc_lines))[0]
+    first_line: str = list(filter(None, doc_lines))[0]
     version_string = first_line.split(' ')[1]
     if not re.compile(r'^[0-9]+\.[0-9]+\.[0-9]+$').match(version_string):
         return None
@@ -144,7 +144,7 @@ def setup(
     # TODO make it possible to add context in userspace and kernel separately, since some context
     # types might only apply to userspace OR kernel; only consider userspace contexts for now
     handles_context = [handle_ust]
-    enabled_handles = list(filter(None, handles_context))
+    enabled_handles: List[lttng.Handle] = list(filter(None, handles_context))
     _add_context(enabled_handles, context_list)
 
     return full_path