X_COVERAGE_UNMEASURED
Means
coverage was read from a suite that did not measure it
Typical cause
three shapes: no lcov record names the package at all, so the percentage is over nothing; the suite wrote no report because it never finished; or files with executable code have no lcov record, which makes them absent from the percentage rather than counted as zero — the one direction an unmeasured file must never move it
Fix
bun test --coverage packages/<pkg> and fix what it reports. For unimported files the finding lists them: import each from a test beside it