The intent of this change is that instead of paths looking like `explorer/testdata/foo/bar.carbon` (repo-relative), they're now just `bar.carbon` (local). The consequence is that paths should be a bit more durable in various environments, and just paths should be shorter and easier to read.
The explorer's prelude is an exception to this since it comes from data, rather than being the test target. Due to the change in approaches, it needs the regex again.
Uses #2829
Isolating test execution time (no build time included):
- Linux, `lit` test-per-file: Elapsed time: 28.214s, Critical Path: 13.97s
- Linux, `cc_test`-per-file: Elapsed time: 11.534s, Critical Path: 6.05s
- Linux, merged `cc_test` with 50 shards: Elapsed time: 11.677s, Critical Path: 11.17s
- Mac, `lit` test-per-file: Elapsed time: 295.686s, Critical Path: 20.00s
- Mac, `cc_test`-per-file: Elapsed time: 55.788s, Critical Path: 3.81s
- Mac, merged `cc_test` with 50 shards: Elapsed time: 16.269s, Critical Path: 7.54s
In GH actions:
- [Before](https://github.com/carbon-language/carbon-lang/actions/runs/4866602695/jobs/8678306144?pr=2799):
- test / test (ubuntu-22.04, fastbuild) (pull_request_target) Successful in 20m
- test / test (ubuntu-22.04, opt) (pull_request_target) Successful in 15m
- test / test (macos-12, fastbuild) (pull_request_target) Successful in 36m
- test / test (macos-12, opt) (pull_request_target) Successful in 21m
- [After](https://github.com/carbon-language/carbon-lang/actions/runs/4875154751/jobs/8697004066?pr=2811):
- test / test (ubuntu-22.04, fastbuild) (pull_request_target) Successful in 10m
- test / test (ubuntu-22.04, opt) (pull_request_target) Successful in 9m
- test / test (macos-12, fastbuild) (pull_request_target) Successful in 12m
- test / test (macos-12, opt) (pull_request_target) Successful in 9m
I'm still leaving a handful of `lit` tests to test end-to-end binary execution. This is why testdata directories are split (`lit` tests next to the `explorer` binary, the `cc_test`s next to `ParseAndExecute`).
Support for global variables is still missing; they're a bit more tricky because they use a pattern to introduce their name.
Prior to this change, explorer heavily relied on name comparisons to determine whether two declarations declare the same entity. Some of those instances are fixed in this PR, but more remain to be fixed, and some TODOs are added for some harder-to-fix instances.
Jon Ross-Perkins
Richard Smith