c56fce9e56
Add support for an inherit_defer statement which works as inherit does but is only evaulated at the end of parsing. This allows conditional expressions to be evaulated 'late' meaning changes to PACKAGECONFIG from bbappends can be applied for example. This addresses a usability/confusion issue users have with the current conditional inherit mechanism since they don't realise the condition has to be expanded immediately with the current model. There is a commented out warning we could enable in future which warns about the use of a conditional inherit that isn't deferred. There is a behaviour difference in the placement of the inherit, particularly around variables set using ?= which means wen swapping from one to the other, caution must be used as values can change. (Bitbake rev: 5c2e840eafeba1f0f754c226b87bfb674f7bea29) Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Bitbake
BitBake is a generic task execution engine that allows shell and Python tasks to be run efficiently and in parallel while working within complex inter-task dependency constraints. One of BitBake's main users, OpenEmbedded, takes this core and builds embedded Linux software stacks using a task-oriented approach.
For information about Bitbake, see the OpenEmbedded website: https://www.openembedded.org/
Bitbake plain documentation can be found under the doc directory or its integrated html version at the Yocto Project website: https://docs.yoctoproject.org
Bitbake requires Python version 3.8 or newer.
Contributing
Please refer to our contributor guide here: https://docs.yoctoproject.org/dev/contributor-guide/ for full details on how to submit changes.
As a quick guide, patches should be sent to bitbake-devel@lists.openembedded.org The git command to do that would be:
git send-email -M -1 --to bitbake-devel@lists.openembedded.org
If you're sending a patch related to the BitBake manual, make sure you copy the Yocto Project documentation mailing list:
git send-email -M -1 --to bitbake-devel@lists.openembedded.org --cc docs@lists.yoctoproject.org
Mailing list:
https://lists.openembedded.org/g/bitbake-devel
Source code:
https://git.openembedded.org/bitbake/
Testing
Bitbake has a testsuite located in lib/bb/tests/ whichs aim to try and prevent regressions. You can run this with "bitbake-selftest". In particular the fetcher is well covered since it has so many corner cases. The datastore has many tests too. Testing with the testsuite is recommended before submitting patches, particularly to the fetcher and datastore. We also appreciate new test cases and may require them for more obscure issues.
To run the tests "zstd" and "git" must be installed.
The assumption is made that this testsuite is run from an initialized OpenEmbedded build
environment (i.e. source oe-init-build-env is used). If this is not the case, run the
testsuite as follows:
export PATH=$(pwd)/bin:$PATH
bin/bitbake-selftest
The testsuite can alternatively be executed using pytest, e.g. obtained from PyPI (in this case, the PATH is configured automatically):
pytest