Add coverage CI job and upload results to codecov.io

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

.gitlab-ci.yml

@@ -5,6 +5,10 @@ variables:
   DISTRO: foxy
   ROS2TRACING_BRANCH: master
 
+stages:
+  - build_test
+  - report
+
 .global_artifacts: &global_artifacts
   artifacts:
     paths:
@@ -16,14 +20,28 @@ variables:
         - build/*/test_results/*/*.xunit.xml
         - build/*/pytest.xml
 
+before_script:
+  - . /root/ws/install/local_setup.sh
+  - python3 get_branch.py --check
+  - git clone https://gitlab.com/micro-ROS/ros_tracing/ros2_tracing.git --branch $(python3 get_branch.py)
+
 build:
+  stage: build_test
   image: $BASE_IMAGE_ID:$DISTRO
-  before_script:
-    - . /root/ws/install/local_setup.sh
   script:
-    - python3 get_branch.py --check
-    - git clone https://gitlab.com/micro-ROS/ros_tracing/ros2_tracing.git --branch $(python3 get_branch.py)
     - colcon build --symlink-install --event-handlers console_cohesion+ --packages-up-to $PACKAGES_LIST
     - colcon test --event-handlers console_cohesion+ --packages-select $PACKAGES_LIST
     - colcon test-result --all
   <<: *global_artifacts
+
+coverage:
+  stage: report
+  image: $BASE_IMAGE_ID:$DISTRO
+  script:
+    - colcon build --symlink-install --event-handlers console_cohesion+ --packages-up-to $PACKAGES_LIST --mixin coverage-pytest --cmake-args -DBUILD_TESTING=ON --no-warn-unused-cli
+    - colcon test --event-handlers console_cohesion+ --packages-select $PACKAGES_LIST --mixin coverage-pytest
+    - colcon test-result --all
+    - bash <(curl -s https://codecov.io/bash)
+    - colcon coveragepy-result --packages-select $PACKAGES_LIST --verbose --coverage-report-args -m
+  allow_failure: true
+  <<: *global_artifacts