Parcel: Parcel won't stop rebuilding in dev mode

[OscarGodson]

🐛 bug report

Running parcel in "dev mode" on OS X just constantly rebuilds which triggers reloads making it impossible to work with :(

🎛 Configuration (.babelrc, package.json, cli command)

package.json

{
  "name": "ozzie",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "start": "parcel ./index.html",
    "test": "mocha --timeout=10000",
    "dbemulator": "firebase serve --only firestore"
  },
  "author": "",
  "license": "ISC",
  "dependencies": {
    "antd": "^3.20.1",
    "dotenv": "^8.0.0",
    "firebase": "^6.3.0",
    "firebase-init": "^1.3.2",
    "formik": "^1.5.8",
    "moment": "^2.24.0",
    "query-string": "^6.8.2",
    "react": "^16.8.6",
    "react-dom": "^16.8.6",
    "react-redux": "^7.1.0",
    "react-redux-firebase": "^3.0.0-alpha.13",
    "react-router-dom": "^5.0.1",
    "recompose": "^0.30.0",
    "redux": "^4.0.4",
    "redux-firestore": "^0.8.0"
  },
  "devDependencies": {
    "@babel/core": "^7.5.5",
    "@babel/plugin-proposal-class-properties": "^7.5.5",
    "@babel/plugin-transform-runtime": "^7.5.5",
    "@babel/preset-env": "^7.5.5",
    "@babel/preset-react": "^7.0.0",
    "@babel/runtime": "^7.5.5",
    "babel-loader": "^8.0.6",
    "babel-polyfill": "^6.26.0",
    "babel-preset-es2015": "^6.24.1",
    "babel-preset-stage-0": "^6.24.1",
    "parcel-bundler": "^1.12.3",
    "@firebase/testing": "0.10.0",
    "filesystem": "1.0.1",
    "mocha": "5.2.0",
    "should": "^13.2.3"
  }
}

.babelrc

{
  "presets": [
    [
      "@babel/preset-env",
      {
        "targets": {
          "browsers": [
            ">0.25%",
            "not ie 11",
            "not op_mini all"
          ]
        }
      }
    ],
    "@babel/preset-react"
  ],
  "plugins": [
    "@babel/plugin-transform-runtime",
    "@babel/plugin-proposal-class-properties"
  ]
}

🤔 Expected Behavior

It should only rebuild and reload when I save a file.

😯 Current Behavior

Constantly rebuilding and causing refreshing. The gif below you can see. I'm doing absolutely nothing but sitting and watching my terminal.

💁 Possible Solution

Maybe not a solution per se but it'd be nice to get some info on _what_ is causing this refresh. Something is triggering a "change" event, but what?

🔦 Context

Just a brain dump but I'm working in IntelliJ. I tried IntelliJ's terminal and iTerm. I've tried deleting node_modules, dist, .cache, and package-lock. I've reinstalled npm modules multiple times.

💻 Code Sample

I can't publicly share the code but it's a _pretty_ simple React app that uses Firebase and Firestore.

🌍 Your Environment

| Software | Version(s) |
| ---------------- | ---------- |
| Parcel | 1.12.3
| Node | 10.16.0
| npm/Yarn | 6.9.0
| Operating System | Mac OS 10.14.1 (18B75)

[OscarGodson]

I'm wondering if this has to do with having it inside of a Dropbox directory. I think Dropbox might be creating temp files or touching files when it sees changes. Is there a way to whitelist or blacklist files?

[DeMoorJasper]

@OscarGodson issues with dropbox has been reported in the past probably good to move it out of dropbox

_{Sent with GitHawk}

[ccssmnn]

Had the same issue today on OSX.

I was able to fix it by moving my project into a directory that is not synced with iCloud Drive.

[liorgrossman]

Having the same issue here, Parcel continuously restarting whenever Dropbox enters sync mode
Did anyone find a fix or a workaround?

[DeMoorJasper]

@liorgrossman it has to do with the watcher detecting file changes made by dropbox... the only workaround is to not have a parcel project in a dropbox folder. Maybe we could eventually debug this and potentially improve our watcher to handle this properly although I doubt we can differentiate it from legitimate updates.

[bobbwhy]

I have this issue and I am not using dropbox.
For me, it happened when I switched branches while parcel was running.
Even after switch complete, the issue still happens

When i ctrl c i get:
@parcel/reporter-dev-server: Could not send success event to devserver because it does not exist.

[DeMoorJasper]

@bobbwhy that sounds like a different issue, feel free to open a new issue

[ManzDev]

Same error with a simple html with link to empty CSS/JS files.

parcel: 2.0.0-beta.1 (and 2.0.0-nightly.432 fails too)
node: 14.14.0 with npm 7
so: Debian 10 with WSL

[DeMoorJasper]

@ManzDev are you running it inside a dropbox or some other kind of cloud storage synced folder?

[ManzDev]

@ManzDev are you running it inside a dropbox or some other kind of cloud storage synced folder?

No, Parcel 1 works fine, but Parcel 2 build constantly. I'm running under WSL (Debian 10). No dropbox.

[DeMoorJasper]

@ManzDev strange, can you create a minimal reproduction?

[ManzDev]

Hi @DeMoorJasper

I created this minimal reproduction and works fine (also with node 14.14.0). But in my system, ocurrs infinite rebuilding.

FROM node:12.19.0-slim
WORKDIR /app
RUN npm init -y && \
    npm install --save-dev parcel@next
RUN mkdir -p src/css src/js
RUN touch src/css/index.css && touch src/js/index.js
COPY index.html /app/src
CMD ["npx", "parcel", "src/index.html"]

[ManzDev]

I create a new example from scratch on my system and now works perfectly.

I have been working fine with no problems for a while.
Sometimes, when write an import to a .js file and save, infinite looping has started.

• If I break (CTLR-C) and restart Parcel, it continues loop.
• If I delete the .parcel-cache folder and restart Parcel, works correctly again.

[DeMoorJasper]

@ManzDev that definitely sounds like some kind of recursion bug, but kind of need a way to reproduce it to debug it properly.

This probably occurred sometime in the past and you still had a cache entry for it which caused it to happen consistently for you but works fine with a new project. I assume the only thing you can do is if it ever happens again to think what you changed before and try and create a reproduction based on that change. I really wished I could help more here as this does sound like a pretty severe bug.

[ManzDev]

I need to test a bit more to see if it happens with some kind of specific pattern. It seems like it doesn't always happens.

I would also like to try on another system. As soon as I know more, I'll post it here. Thank you very much!

[bp9320]

I had the same issue on MacOS (Catalina 10.15.7, Node 14.14.0, Parcel 2.0.0-nightly.440).

Like @ManzDev, deleting the .parcel-cache folder stopped the constant build process (thanks for that tip!), but I noticed it started happening again after I got a build error. I have reproduced it in this way roughly six times, though I have not tried in other projects.

[AndrewKvalheim]

This consistently reproduces it for me:

$ yarn add --dev [email protected]
$ touch a.html
$ echo '<a href="a.html">' > b.html
$ ( sleep 3s && touch a.html ) & parcel watch a.html b.html | grep 'Built in'
✨ Built in 294ms
✨ Built in 21ms
✨ Built in 9ms
✨ Built in 13ms
✨ Built in 9ms
✨ Built in 8ms
✨ Built in 9ms
✨ Built in 12ms
✨ Built in 16ms
✨ Built in 14ms
^C

Coarsely bisecting nightlies:

• Unaffected: 300–319
• Crashes: 320–333
• Affected: 337–475

(Node v15.3.0, Yarn 1.22.5, Ubuntu 20.04.1 LTS; no Dropbox)

[stevematney]

I was able to get the constant rebuild to stop by following these instructions for Dropbox to ignore files or folders, and ignoring node_modules, dist, and .parcel-cache.

I have not gone through the steps to narrow down exactly which folder was the culprit, but I figure it's not very important that Dropbox track those files anyway.

[mischnic]

Might or might not be the same bug as https://github.com/parcel-bundler/parcel/issues/5355

[RohanG0407]

Every time I make a change in a sass file, it seems to keep infinitely rebuilding. Anyone had this happen to them? I can fix this by deleting parcel-cache and if I make edits in any other files it builds only once. Only sass files it keeps rebuilding

[DestroyOnLoad]

I create a new example from scratch on my system and now works perfectly.

I have been working fine with no problems for a while.
Sometimes, when write an import to a .js file and save, infinite looping has started.

• If I break (CTLR-C) and restart Parcel, it continues loop.
• If I delete the .parcel-cache folder and restart Parcel, works correctly again.

Thank you! Completely the issue I was dealing with. Not sure what was in the cache triggering the change event, but it's simple enough to let parcel just rebuild.