Validate a test/example binary before running it. Returns ``None`` if the artifact is fresh and ready to run. Returns a populated ``TestResult`` (``success=False``) if the artifact is missing or stale, so the caller can surface the failure directly instead of silently running broken
(
test_path: Path, build_start_time: float
)
| 41 | |
| 42 | |
| 43 | def validate_test_artifact( |
| 44 | test_path: Path, build_start_time: float |
| 45 | ) -> Optional[TestResult]: |
| 46 | """Validate a test/example binary before running it. |
| 47 | |
| 48 | Returns ``None`` if the artifact is fresh and ready to run. Returns |
| 49 | a populated ``TestResult`` (``success=False``) if the artifact is |
| 50 | missing or stale, so the caller can surface the failure directly |
| 51 | instead of silently running broken/old code. |
| 52 | |
| 53 | Why this matters (FastLED #3011): the streaming compiler submits |
| 54 | tests to the runner as soon as Ninja prints ``[N/M] Linking <X>`` |
| 55 | — but that line is Ninja's PRE-link announcement, NOT a success |
| 56 | signal. If the link then FAILS (zccache daemon crash under the |
| 57 | parallel-link storm, ld.lld permission error, etc.) ``test_path`` |
| 58 | is either missing entirely (clean build) or stale from a previous |
| 59 | build sitting in the same build dir. Running it produces a |
| 60 | false pass or false fail; refusing to run it surfaces the link |
| 61 | failure where it belongs. |
| 62 | """ |
| 63 | if not test_path.exists(): |
| 64 | return TestResult( |
| 65 | success=False, |
| 66 | output=( |
| 67 | f"[MESON] ❌ Test artifact missing: {test_path}\n" |
| 68 | f" Link likely failed during the parallel-link storm " |
| 69 | f"(zccache daemon crash, ld.lld error, etc.) — see " |
| 70 | f"FastLED #3011. Refusing to run a missing DLL.\n" |
| 71 | f" Resolve the underlying link failure and re-run." |
| 72 | ), |
| 73 | ) |
| 74 | try: |
| 75 | dll_mtime = test_path.stat().st_mtime |
| 76 | except OSError: |
| 77 | # stat() failure is non-fatal — let the subprocess loader |
| 78 | # surface whatever it actually sees on disk. |
| 79 | return None |
| 80 | if dll_mtime < build_start_time: |
| 81 | return TestResult( |
| 82 | success=False, |
| 83 | output=( |
| 84 | f"[MESON] ❌ Stale test artifact: {test_path}\n" |
| 85 | f" DLL mtime ({dll_mtime:.2f}) predates this build's " |
| 86 | f"start ({build_start_time:.2f}). The current link " |
| 87 | f"likely failed and left a previous build's DLL behind " |
| 88 | f"— running it would produce misleading results (see " |
| 89 | f"FastLED #3011).\n" |
| 90 | f" Resolve the underlying link failure (`zccache stop` " |
| 91 | f"+ retry usually clears the daemon-crash variant) and " |
| 92 | f"re-run." |
| 93 | ), |
| 94 | ) |
| 95 | return None |
| 96 | |
| 97 | |
| 98 | @dataclass |