`ruby-dataset-measure.yml` is not updated yet as it requires aid from the language team.
We can presumably disable the workflow during the brownout periods, but a fix will have to be present before the full deprecation happens
Previously the cache would become stale. Now the same incremental
cache mechanism in use for the QL cache is adopted (and factored out
in a separate action).
Namely, pushes on main will populate the cache using the commit hash as
key, while PRs will try to use the cache of their merge base, read-only.
To avoid the cache growing out of control, a simple cache eviction is
done on pushes.
This is a developer QoL improvement, where running codegen will skip
writing (and especially formatting) any files that were not changed.
**Why?** While code generation in itself was pretty much instant, QL
formatting of generated code was starting to take a long time. This made
unconditionally running codegen quite annoying, for example before each
test run as part of an IDE workflow or as part of the pre-commit hook.
**How?** This was not completely straightforward as we could not work
with the contents of the file prior to code generation as that was
already post-processed by the QL formatting, so we had no chance of
comparing the output of template rendering with that. We therefore store
the hashes of the files _prior_ to QL formatting in a checked-in file
(`swift/ql/.generated.list`). We can therefore load those hashes at
the beginning of code generation, use them to compare the template
rendering output and update them in this special registry file.
**What else?** We also extend this mechanism to detect accidental
modification of generated files in a more robust way. Before this patch,
we were doing it with a rough regexp based heuristic. Now, we just store
the hashes of the files _after_ QL formatting in the same checked file,
so we can check that and stop generation if a generated file was
modified, or a stub was modified without removing the `// generated`
header.
* A unique workflow file has been created merging all `swift-*.yml`
workflows
* Change filtering at job level was added using [dorny/paths-filter][1]
* only one build of the extractor is made, and then shared via cache
(not as an artifact because of [this longstading issue][2])
* integration tests are now run on on macOS
* qltests are not run any more on macOS to cut on feedback time
* autobuilder tests were moved to the macOS build step to avoid loading
bazel twice
[1]: https://github.com/dorny/paths-filter#examples
[2]: https://github.com/actions/upload-artifact/issues/38
