The lit-based test runner introduced in c776a52f only discovered
libc.test.src tests with a strict __unit__.__build__ or
__hermetic__.__build__ suffix. This missed four categories of tests:
1. libc.test.include.* tests (e.g. isnan_test, signbit_test)
2. libc.test.integration.* tests (e.g. pthread, unistd, startup)
3. libc.test.src.* tests that have no __unit__/__hermetic__ marker (e.g.
errno_test, dirent_test, htonl)
4. libc.test.src.* tests with extra option suffixes between the type
marker and .__build__ (e.g. __unit__.__NO_FMA_OPT.__build__)
Wire up the two missing build dependencies so that check-libc-lit builds
include and integration tests before running them, and update
_isTestExecutable() to recognise all four patterns.
The pattern documentation was consolidated into the _isTestExecutable()
docstring, where it is next to the code it describes, to avoid the two
diverging in future.
Tested:
Compared the test count from a full `ninja check-libc` run (2765 tests)
against `llvm-lit --show-tests libc/test` after this change and
confirmed the counts match exactly.
7b7c8b2eb3