Proof

expo-print

printAsync routes through real window.print() (browser print dialog). printToFileAsync now produces a REAL, structurally-valid PDF (verified by `file`/macOS as com.adobe.pdf) carrying the html's text content + a real page count, written to the same in-memory cache the expo-file-system stub serves — so the returned `<cacheDirectory>Print/*.pdf` URI resolves to genuine PDF bytes (readAsStringAsync / FormData upload / Sharing / Print preview all work), and base64 (when requested) decodes to those bytes. This replaces the old `mock://print.pdf` dangling URI that broke every consumer. Fidelity caveat: the worker has no WebView render engine, so the PDF reproduces the document's TEXT (paginated, escaped) but NOT CSS/image layout — a degraded-but-real simulation of iOS's WKWebView→UIPrintPageRenderer output.
80%
API coverage
No visual proof cases have been published for this package yet. The registry summary below describes what the compat layer implements.
Working (5)
upstream validation and concurrency guardprintAsync (real window.print)printToFileAsync (real PDF bytes: %PDF header, catalog/pages tree, xref, paginated text content, real numberOfPages, real file:// uri + base64)selectPrinterAsyncOrientation enum
Missing (4)
CSS/image/font layout fidelity in the generated PDF (text-only render — needs a worker WebView engine to match WKWebView pixel output)useMarkupFormatter (same text path)printerUrl/AirPrint physical printingnative printer selection sheet (selectPrinterAsync returns undefined)