diff options
Diffstat (limited to '')
-rw-r--r-- | tests/coverage/README.md | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/tests/coverage/README.md b/tests/coverage/README.md new file mode 100644 index 000000000..c72aa69c0 --- /dev/null +++ b/tests/coverage/README.md @@ -0,0 +1,16 @@ +The tests in this directory are shared by two different test modes, and can be +run in multiple different ways: + +- `./x.py test coverage-map` (compiles to LLVM IR and checks coverage mappings) +- `./x.py test coverage-run` (runs a test binary and checks its coverage report) +- `./x.py test coverage` (runs both `coverage-map` and `coverage-run`) + +## Maintenance note + +These tests can be sensitive to small changes in MIR spans or MIR control flow, +especially in HIR-to-MIR lowering or MIR optimizations. + +If you haven't touched the coverage code directly, and the tests still pass in +`coverage-run` mode, then it should usually be OK to just re-bless the mappings +as necessary with `./x.py test coverage-map --bless`, without worrying too much +about the exact changes. |