This document is a declaration of software quality for the `tracetools` package, based on the guidelines in [REP-2004](https://www.ros.org/reps/rep-2004.html).
Below are the rationales, notes, and caveats for this claim, organized by each requirement listed in the [Package Requirements for Quality Level 1 in REP-2004](https://www.ros.org/reps/rep-2004.html).
## Version Policy [1]
### Version Scheme [1.i]
`tracetools` uses `semver` according to the recommendation for ROS Core packages in the [ROS 2 Developer Guide](https://index.ros.org/doc/ros2/Contributing/Developer-Guide/#versioning).
All symbols in the installed headers are considered part of the public API.
All installed headers are in the `include` directory of the package, headers in any other folders are not installed and considered private.
### API Stability Within a Released ROS Distribution [1.iv]/[1.vi]
`tracetools` will not break public API within a released ROS distribution, i.e. no major releases once the ROS distribution is released.
### ABI Stability Within a Released ROS Distribution [1.v]/[1.vi]
`tracetools` will maintain ABI stability within a ROS distribution.
## Change Control Process [2]
`tracetools` follows the recommended guidelines for ROS Core packages in the [ROS 2 Developer Guide](https://index.ros.org/doc/ros2/Contributing/Developer-Guide/#change-control-process).
All merge requests must have at least one peer review.
### Continuous Integration [2.iv]
All merge requests must pass CI on Ubuntu amd64.
Nightly results for all [tier 1 platforms as defined in REP-2000](https://www.ros.org/reps/rep-2000.html#support-tiers) can be found here (note that only the tagged release used in the [`ros2.repos`](https://github.com/ros2/ros2/blob/master/ros2.repos) file is tested nightly):
All merge requests must resolve related documentation changes before merging.
## Documentation [3]
`tracetools` does not currently follow all the recommended guidelines for ROS Core packages in the [ROS 2 Developer Guide](https://index.ros.org/doc/ros2/Contributing/Developer-Guide/#documentation).
### Feature Documentation [3.i]
`tracetools` has [documentation](../doc/design_ros_2.md) for all of its features, and new features require documentation before being added.
It does not currently have a features list with links to the corresponding feature documentation.
`tracetools` has embedded API documentation which can be generated using doxygen. The latest version can be viewed [here](https://micro-ros.gitlab.io/ros_tracing/ros2_tracing-api/).
New additions to the public API require documentation before being added.
The license for `tracetools` is Apache 2.0, and a summary is in each source file, the type is declared in the `package.xml` manifest file, and a full copy of the license is in the [`LICENSE`](./LICENSE) file.
There is an automated test which runs a linter that ensures each file has a license statement.
### Copyright Statement [3.iv]
The copyright holders each provide a statement of copyright in each source code file in `tracetools`.
There is an automated test which runs a linter that ensures each file has at least one copyright statement.
## Testing [4]
### Feature Testing [4.i]
Each feature in `tracetools` has corresponding system tests which simulate typical usage, and they are located in the `tracetools_test` package.
New features are required to have tests before being added.
### Public API Testing [4.ii]
Each part of the public API has tests, and new additions or changes to the public API require tests before being added.
The tests aim to cover both typical usage and corner cases, but are quantified by contributing to code coverage.
### Coverage [4.iii]
`tracetools` follows the recommendations for ROS Core packages in the [ROS 2 Developer Guide](https://index.ros.org/doc/ros2/Contributing/Developer-Guide/#code-coverage).
This includes:
- tracking and reporting line coverage statistics
- no lines are manually skipped in coverage calculations
Changes are required to make a best effort to keep or increase coverage before being accepted, but decreases are allowed if properly justified and accepted by reviewers.
Current coverage statistics can be viewed in the [results of the latest `coverage` CI job](https://gitlab.com/micro-ROS/ros_tracing/ros2_tracing/pipelines/latest).
### Performance [4.iv]
`tracetools` does not currently have any performance tests.
### Linters and Static Analysis [4.v]
`tracetools` uses and passes all the standard linters and static analysis tools as described in the [ROS 2 Developer Guide](https://index.ros.org/doc/ros2/Contributing/Developer-Guide/#linters-and-static-analysis).
## Dependencies [5]
`tracetools` has a few "buildtool" dependencies, which do not affect the resulting quality of the package, because they do not contribute to the public library API.
It also has a few test dependencies, which do not affect the resulting quality of the package, because they are only used to build and run the test code.
### Direct Runtime ROS Dependencies [5.i]
This package does not have any runtime ROS dependencies.
### Optional Direct Runtime ROS Dependencies [5.ii]
This package does not have any optional runtime ROS dependencies.
### Direct Runtime non-ROS Dependency [5.iii]
`tracetools` has a run-time dependency on [LTTng](https://lttng.org/docs/v2.11/). A Quality Level review for LTTng has yet to be done.
## Platform Support [6]
`tracetools` supports all of the tier 1 platforms as described in [REP-2000](https://www.ros.org/reps/rep-2000.html#support-tiers), and tests each change against all of them.
However, due to the nature of its features, they only work on Linux-based systems.
Comparing this table to the [Quality Level Comparison Chart of REP-2004](https://www.ros.org/reps/rep-2004.html#quality-level-comparison-chart) led us to conclude that this package qualifies for Quality Level 3.
