webpack 5 - hmr check api no longer returns updated modules

[lukeapage]

Bug report

webpack-contrib/webpack-hot-middleware#390

I've been investigating the cause.

as per the documentation https://webpack.js.org/api/hot-module-replacement/#check
it expects check to yield an array of updated modules. It uses this to compare to the updated modules in order to decide whether to reload.

when I debug I see:

https://github.com/webpack/webpack/blob/master/lib/hmr/HotModuleReplacement.runtime.js#L257
check doesn't add any modules, it passes the array to the runtime to update.

https://github.com/webpack/webpack/blob/master/lib/hmr/JavascriptHotModuleReplacement.runtime.js#L413
The runtime doesn't add any modules, but it passes the array on to the loader

webpack/lib/web/JsonpChunkLoadingRuntimeModule.js

Line 280 in 80c5041

"function loadUpdateChunk(chunkId) {",

The loader doesn't accept the second argument so it doesn't add any modules to the array

It looks like a bug because the documentation wasn't changed and the code still references the updatedModules array.

Seems it was introduced in webpack 5 alpha. 0 here:
9d91861#diff-99b22d1932803b7795bbe843d01cdf63d32e52a247610bfd9cffb95170227cc6

it seems that the node/ version had the updated module id's, but the web version does not.

Other relevant information:
webpack version: 5.3.1
Node.js version: 12
Operating System: windows 10
Additional tools:

[alexander-akait]

/cc @sokra

[samhuk]

Just an FYI: I created an issue with webpack-hot-middleware that details an eventual side-effect of this: webpack-contrib/webpack-hot-middleware#398. I believe that it's the exact same thing going on as in your linked issue (webpack-contrib/webpack-hot-middleware#390)

[webpack-bot]

This issue had no activity for at least three months.

It's subject to automatic issue closing if there is no activity in the next 15 days.

[alexander-akait]

bump

[rocalvo-meli]

Hi! I'm facing the same problem, there is any update ?

[otakustay]

Facing the same issue, by stepping into it a little further, I find this code in node_modules/webpack/lib/hmr/JavascriptHotModuleReplacement.runtime.js at around line 439：

chunkIds.forEach(function (chunkId) {
	if (
		$hasOwnProperty$($installedChunks$, chunkId) &&
		$installedChunks$[chunkId] !== undefined
	) {
		// HERE
		promises.push($loadUpdateChunk$(chunkId, updatedModulesList));
		currentUpdateChunks[chunkId] = true;
	}
});

This calls loadUpdateChunk with 2 arguments, however inside node_modules/webpack/lib/web/JsonpChunkLoadingRuntimeModule.js around line 273, loadUpdateChunk is defined as:

? Template.asString([
		"var currentUpdatedModulesList;",
		"var waitingUpdateResolves = {};",
		// HERE
		"function loadUpdateChunk(chunkId) {",
		Template.indent([
			`return new Promise(${runtimeTemplate.basicFunction(
				"resolve, reject",
				[

It only defines one parameter, it never pushes any entry into updatedModulesList array, causing hot.check fails to report updated modules.

But weirdly, this long lived issue only affects us in recent several days when we deleted our lock file and have a fresh install, not sure if there is any other root causes

[TrejGun]

bump

[Herz3h]

any news on this ?

[tangtangtangtangtang]

is there any progress?

[sokra]

Send a PR

[vankop]

fixed