wrangler preview --watch only detects the first change (on Linux)

[kentonv]

🐛 Bug Report

Environment

• operating system: Linux (Debian Buster; kernel 4.19.37)
• output of rustc -V: N/A
• output of node -v: N/A
• output of wrangler -V: 1.2.0

Steps to reproduce

1. Run wrangler preview --watch.
2. See preview.
3. Make a change to the code.
4. See preview update. Cool!
5. Make another change to the code.

What did you expect to see?

Preview updates again.

What did you see instead?

Preview did not update.

The full output of Wrangler at this point is:

 JavaScript project found. Skipping unnecessary build!
 watching "worker.js"
 Detected changes...
 Detected change during cooldown...
 Cooldown over, propogating changes...
 Updated preview with changes

No matter how many times I make changes to worker.js, no more output is shown and the preview is not updated.

It appears that Wrangler is failing to notice the file changing after the first time. Since file change notification APIs vary wildly across platforms, it's very possible this bug is Linux-specific.

[gabbifish]

Hi there!

Thanks for reporting this. I was able to reproduce this with a Javascript worker. It looks like live reload works for multiple iterations to Webpack workers (the default Wrangler worker type), so I suspect this may not be a problem with the file change notification API, but rather a logic problem in Wrangler. I'll investigate. :)