[Bug]: Flaky input.files.count on firefox after setInputFiles #29683
Description
Version
1.41.1
Steps to reproduce
- Run
npm start
Expected behavior
the test always runs correctly
Actual behavior
the test always runs correctly only on local machine
In docker image test fails (with a probability of 20%) with error:
Error: expect(received).resolves.toBe(expected) // Object.is equality
Expected: 2
Received: 0
22 | ]);
23 |
> 24 | await expect(fileChangePromise).resolves.toBe(2);
| ^
25 | });
26 |
Additional context
Hi guys! In Firefox, an automated test scenario that involves setting files for an element intermittently fails to correctly reflect the number of files selected. Specifically, when listening for the change event on the file input and then checking the files.length property of the input, the test sometimes observes a value of 0 instead of the expected number of files that were programmatically set. This issue does not consistently reproduce but occurs often enough to significantly impact test reliability.
Environment
System:
OS: macOS 14.3
CPU: (10) arm64 Apple M1 Pro
Memory: 1.25 GB / 32.00 GB
Binaries:
Node: 16.20.2 - ~/.nvm/versions/node/v16.20.2/bin/node
npm: 8.19.4 - ~/.nvm/versions/node/v16.20.2/bin/npm
Languages:
Bash: 3.2.57 - /bin/bash
npmPackages:
@playwright/test: ^1.40.1 => 1.41.1