Add a few notes about how testing works in U-Boot.
Signed-off-by: Simon Glass sjg@chromium.org ---
test/README | 82 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 82 insertions(+) create mode 100644 test/README
diff --git a/test/README b/test/README new file mode 100644 index 0000000..dfd83d6 --- /dev/null +++ b/test/README @@ -0,0 +1,82 @@ +Testing in U-Boot +================= + +U-Boot has a large amount of code. This file describes how this code is +tested and what tests you should write when adding a new feature. + + +Sandbox +------- +U-Boot can be built as a user-space application (e.g. for Linux). This +allows test to be executed without needing target hardware. The 'sandbox' +target provides this feature and it is widely used in tests. + + +Pytest Suite +------------ + +Many tests are available using the pytest suite, in test/py. This can run +either on sandbox or on real hardware. It relies on the U-Boot console to +inject test commands and check the result. It is slower to run than C code, +but provides the ability to unify lots of test and summarise their results. + +You can run the tests on sandbox with: + + ./test/py/test.py --bd sandbox --build + +This will produce HTML output in build-sandbox/test-log.html + +See test/py/README.md for more information about the pytest suite. + + +tbot +---- + +Tbot provides a way to execute tests on target hardware. It is intended for +trying out both U-Boot and Linux (and potentially other software) on a +number of boards automatically. It can be used to create a continuous test +environment. See tools/tbot/README for more information. + + +Ad-hoc tests +------------ + +There are several ad-hoc tests which run outside the pytest environment: + + test/fs - File system test (shell script) + test/image - FIT and lagacy image tests (shell script and Python) + test/stdint - A test that stdint.h can be used in U-Boot (shell script) + trace - Test for the tracing feature (shell script) + vboot - Test for verified boot (shell script) + +The above should be converted to run as part of the pytest suite. + + +When to write tests +------------------- + +If you add code to U-Boot without a test you are taking a risk. Even if you +perform thorough manual testing at the time of submission, it may break when +future changes are made to U-Boot. It may even break when applied to mainline, +if other changes interact with it. A good mindset is that untested code +probably doesn't work and should be deleted. + +You can assume that the Pytest suite will be run before patches are accepted +to mainline, so this provides protection against future breakage. + +On the other hand there is quite a bit of code that is not covered with tests, +or is covered sparingly. So here are some suggestions: + +- If you are adding a new uclass, add a sandbox driver and a test that uses it +- If you are modifying code covered by an existing test, add a new test case + to cover your changes +- If the code you are modifying has not tests, consider writing one. Even a + very basic test is useful, and may be picked up and enhanced by others. It + is much easier to add onto a test - writing a new large test can seem + daunting to most contributors. + + +Future work +----------- + +Converting existing shell scripts into pytest tests.