WPT
wpt / fs / FileSystemWritableFileStream.https.any.worker.html
Spec: File System ↗
Runs: Chrome 155.0.8042.0 (wpt@a1ecd0c09, 2026-09-04) | Firefox 157.0a1 (wpt@a1ecd0c09, 2026-09-04) | Safari 251 preview (wpt@e7122b73f, 2026-09-04) | Ladybird 1.0-52f0f (wpt@0588f3896, 2026-09-04) | Servo Servo 0.6 (wpt@2c385f65e, 2026-09-04) | Blitz a50cb8971 (wpt@a95401e4e, 2026-09-03)
View on the Blitz WPT dashboard | Open test on wpt.live | wpt.fyi
| Chrome | Firefox | Safari | Ladybird | Servo | Blitz | |
|---|---|---|---|---|---|---|
| Total | 8/9 | 7/9 | 8/9 | 0/9 | 0/9 | NOT RUN |
| Subtest | Chrome | Firefox | Safari | Ladybird | Servo | Blitz |
|---|---|---|---|---|---|---|
| truncate() to shrink a file | PASS | PASS | PASS | FAIL | FAIL | — |
| truncate() to grow a file | PASS | PASS | PASS | FAIL | FAIL | — |
| createWritable() fails when parent directory is removed | PASS | FAIL | PASS | FAIL | FAIL | — |
| createWritable({keepExistingData: true}): atomic writable file stream initialized with source contents | PASS | PASS | PASS | FAIL | FAIL | — |
| createWritable({keepExistingData: false}): atomic writable file stream initialized with empty file | PASS | PASS | PASS | FAIL | FAIL | — |
| createWritable() can be called on two handles representing the same file | FAIL | FAIL | FAIL | FAIL | FAIL | — |
| cursor position: truncate size > offset | PASS | PASS | PASS | FAIL | FAIL | — |
| cursor position: truncate size < offset | PASS | PASS | PASS | FAIL | FAIL | — |
| commands are queued, stream is unlocked after each operation | PASS | PASS | PASS | FAIL | FAIL | — |