Instead of crashing when run outside of `bazel`, make the toolchain's
`file_test` binary work properly when no test-specific environment
variables are set. This makes it a lot easier to run `file_test` under a
debugger.
There are two main changes here:
- Don't crash if `$TEST_TMPDIR` is unset. Instead, fall back to LLVM's
temporary directory (typically `$TMPDIR`). We already did this in some
places in tests. We now do it in more places.
- Don't fall back to a target label of `<target>` in the reproduction
commands if `$TEST_TARGET` is unset, because this causes all the tests
to fail because their output doesn't match the expected output due to a
differing bazel run command. Instead explicitly specify the target from
the `FileTestBase`-derived class.
Infrastructure for this has been added generally, but only rolled out to
the toolchain `file_test` binary for now.
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Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
Small cleanup for code sharing. Note, `*ReadFile` will trigger a
CHECK-failure on error; the relevant implementations would previously
have failed silently (empty string).
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Co-authored-by: Richard Smith <richard@metafoo.co.uk>
Richard SmithandJon Ross-Perkins
Thomas Köppe
Chandler Carruth