[DEP_WEBPACK_WATCH_WITHOUT_CALLBACK] error when using --watch flag

[sanex3339]

Describe the bug

PR with the configuration
javascript-obfuscator/javascript-obfuscator#776

After upgrade from webpack@4 to webpack@5 and webpack-cli@3 to webpack-cli@4.0.0 I got the following error:

[DEP_WEBPACK_WATCH_WITHOUT_CALLBACK] DeprecationWarning: A 'callback' argument need to be provided to the 'webpack(options, callback)' function when the 'watch' option is set. There is no way to handle the 'watch' option without a callback.

This error happens only when using --watch flag:

webpack --config ./webpack/webpack.node.config.js --mode development --watch

Full error trace:

(node:62890) [DEP_WEBPACK_WATCH_WITHOUT_CALLBACK] DeprecationWarning: A 'callback' argument need to be provided to the 'webpack(options, callback)' function when the 'watch' option is set. There is no way to handle the 'watch' option without a callback.
    at webpack (/Users/sanex/WebstormProjects/javascript-obfuscator/node_modules/webpack/lib/webpack.js:145:5)
    at f (/Users/sanex/WebstormProjects/javascript-obfuscator/node_modules/webpack/lib/index.js:35:15)
    at Compiler.createCompiler (/Users/sanex/WebstormProjects/javascript-obfuscator/node_modules/webpack-cli/lib/utils/Compiler.js:129:35)
    at WebpackCLI.run (/Users/sanex/WebstormProjects/javascript-obfuscator/node_modules/webpack-cli/lib/webpack-cli.js:220:32)
    at async runCLI (/Users/sanex/WebstormProjects/javascript-obfuscator/node_modules/webpack-cli/lib/bootstrap.js:74:24)

Expected behavior

No error.

[alexander-akait]

@webpack/cli-team high priority

[photonstorm]

I get the same error, but I think it's worth mentioning that the watch mode does actually work. Yes, it throws that warning at the start, but it still bundles and still watches for changes correctly.

[raduchiriac]

Indeed, webpack v5 does not watch anymore if I remove --watch and do webpack --config webpack.config.js

I use this config:

{
  mode: "development",
  watch: true,
  devtool: "inline-cheap-source-map",
  watchOptions: {
    ignored: ["node_modules/**"],
  },
  entry: {
    main: ["core-js/stable", "./src/js/index.js"],
    theme: "./src/scss/th.scss",
  },
}

Solution: With my config above the only way to go is adding --watch which I'd prefer not to

[snitin315]

I will fix it 👍

[alexander-akait]

We have two problems here:

• watch without callback
• we don't respect the watch option from config

[snitin315]

@evilebottnawi fixed with #1931 ?

[alexander-akait]

@snitin315 No, will be fixed in the near future, the next PR

[alexander-akait]

Some problems on webpack side with new API, we are working on it, so I will do release with other fixes, but it will be fixed tomorrow with patch release

[gimmi]

Same problem for me when trying to upgrade to webpack@5.1.3 and webpack-cli@4.0.0

[alexander-akait]

@gimmi why need to spam it? I've always tried to figure it out, but I can't, can you explain it to me?

[alexander-akait]

Just note, this is unnecessary using --watch and watch: true together, just remove watch: true from the config

[jakebailey]

I hit this with the latest versions of everything and I don't have watch: true set, so I don't think this config option being duplicated is the whole story.

[alexander-akait]

@jakebailey Can you provide link on example of problem, removing watch: true should help

[jakebailey]

I haven't yet pushed the changes to my project to grab 4.1.0 quite yet (holding back dep updates for a release, but will likely do it soon), but the config that it'd be is here: https://github.com/microsoft/pyright/blob/master/packages/vscode-pyright/webpack.config.js

Where the task just runs webpack --mode development --watch --progress.

[alexander-akait]

@jakebailey Very strange, should be no problems

[jasonwilliams]

I have this with this project https://github.com/styled-components/vscode-styled-components/blob/master/package.json and we don’t have watch: true set.
Looks like 4.1.0 is out so we will try that

[tkurki]

I just created https://gist.github.com/tkurki/5627039d52ca0248648ed383294f57f6 and with that I get the DeprecationWarning running npx webpack --watch. Install gave me 4.1.0.

[chadleong]

I am running webpack 5.1.3 and webpack-cli 4.1.0 with

"dev": "webpack --mode development --watch ./src/frontend/src/index.js -o ./src/frontend/static/frontend/"

Still get the same [DEP_WEBPACK_WATCH_WITHOUT_CALLBACK] error

[piecyk]

Had a quick look and removing watch: true from config will not help as --watch is still propagated to options

https://github.com/webpack/webpack/blob/master/lib/webpack.js#L140

Looks like we would need to refactor how the webpack-cli handles complier ( have some wip already but would require webpack/webpack#11784 )

[alexander-akait]

@piecyk Can you clarify?

[piecyk]

Can you clarify?

@evilebottnawi on which part ?

webpack-cli creates compiler via https://github.com/webpack/webpack-cli/blob/master/packages/webpack-cli/lib/webpack-cli.js#L219

Using --watch will set {watch: true} on this.compilerConfiguration that we pass as option to webpack. On webpack side we create compiler without callback that's why it logs a warning at https://github.com/webpack/webpack/blob/master/lib/webpack.js#L140

Looks like there is no option to opt out from warning just to pass a callback when calling webpack(...)

[alexander-akait]

Using --watch will set {watch: true} on this.compilerConfiguration that we pass as option to webpack.

We should fix it

Also we can remove watch: true from config when you run webpack --watch with warnings message

[thisVioletHydra]

√ Webpack
  Compiled successfully in 1.55s

[webpack-cli] Compilationdevelopment starting...
(node:10048) [DEP_WEBPACK_WATCH_WITHOUT_CALLBACK] DeprecationWarning: A 'callback' argument need to be provided to the 'webpack(options, callback)' function when the 'watch' option is set. There is no way to handle the 'watch' option without a callback.
(Use `node --trace-deprecation ...` to show where the warning was created)

[nestorvanz]

I did update to "webpack": "^5.3.2" and the error still appears

[DEP_WEBPACK_WATCH_WITHOUT_CALLBACK] DeprecationWarning: A 'callback' argument need to be provided to the 'webpack(options, callback)' function when the 'watch' option is set. There is no way to handle the 'watch' option without a callback.

[jdelStrother]

I think we're still waiting on a new release ( > 4.1.0 ) for this. If I test against the master branch it seems to work fine.

(You can use the master branch with yarn add --dev https://gitpkg.now.sh/webpack/webpack-cli/packages/webpack-cli)

EDIT: which is weird because allegedly 4.1.0 was the one that fixed watch mode. I'm still trying to narrow down exactly what fixed it... The deprecation warning was fixed in 2cb0c0e

[alexander-akait]

Release will be today

[alexander-akait]

Fixed in webpack-cli@4.2.0, if somebody faced with the problem again, please open a new issue with reproducible test repo, because we tests most of cases 😄

[xccjk]

Fixed in webpack-cli@4.2.0, if somebody faced with the problem again, please open a new issue with reproducible test repo, because we tests most of cases 😄

I still have this problem!

"webpack": "^5.10.3",
"webpack-cli": "^4.2.0",
"webpack-dev-server": "^3.11.0"

node: v14.15.0
npm: 6.14.8
mac: 10.14.6

github

[pedro-w]

@xccjk I did a fresh checkout of your https://github.com/xccjk/webpack-demo1 and didn't see this problem.

I did see a "DEP_WEBPACK_COMPILATION_ASSETS" but this comes from html-webpack-plugin

• node v14.15.1
• npm 6.14.8
• Windows 10 x64

[xccjk]

@xccjk I did a fresh checkout of your https://github.com/xccjk/webpack-demo1 and didn't see this problem.

I did see a "DEP_WEBPACK_COMPILATION_ASSETS" but this comes from html-webpack-plugin

• node v14.15.1
• npm 6.14.8
• Windows 10 x64

Thank you very much for your reply, but after removing html-webpack-plugin, I still have the same problem. I updated the github address after removing redundant packages

• node v14.15.0
• npm 6.14.8
• mac 10.14.6

[lebadapetru]

"webpack": "^5.12", and this still occurs

[alexander-akait]

You need update webpack-cli to the latest stable version

[lebadapetru]

i'm not actually using pure webpack but webpack encore which uses webpack-cli 4, i see that 4.5 is the latest version but i guess i'll have to wait for webpack encore to upgrade it

[chadleong]

Running latest webpack 5.22 and webpack-cli 4.5 - No errors !

[PeterBowater]

Once I had updated webpack-cli it was all good :)

[xeroxstar]

"webpack": "^5.61.0" getting same warning when I set the watch property value to true in the config file and running this code:

let entries = [{
    watch : true
}];
let compiler = webpack(entries);
compiler.watch({
    aggregateTimeout: 1000,
    poll: undefined
},(err, stats) => {})

if I set to false the watch property value in config so the warning is gone. Anyway, this warning I guess is harmless so it's not big deal.