Use assetEmitted hook to mitigate futureEmitAssets = true

[qnighy]

Status

READY

Description

Webpack 4.39 introduced a new flag called futureEmitAssets which forbids referencing asset contents after emitting.

With futureEmitAssets = true, we observe the following error:

% yarn build
yarn run v1.19.2
$ react-app-rewired build --scripts-version react-scripts
Creating an optimized production build...
./node_modules/webpack/lib/Compiler.js:713
		throw this._error();
		^

Error: Content and Map of this Source is no longer available (only size() is supported)
    at SizeOnlySource._error (./node_modules/webpack/lib/Compiler.js:699:10)
    at SizeOnlySource.source (./node_modules/webpack/lib/Compiler.js:713:14)
    at HoneybadgerSourceMapPlugin.uploadSourceMap (./node_modules/honeybadger-webpack/dist/HoneybadgerSourceMapPlugin.js:168:67)
    at ./node_modules/honeybadger-webpack/node_modules/async/dist/async.js:2158:44
    at eachOfArrayLike (./node_modules/async/dist/async.js:504:13)
    at eachOf (./node_modules/async/dist/async.js:555:16)
    at awaitable(eachOf) (./node_modules/async/dist/async.js:208:32)
    at Object.eachLimit (./node_modules/async/dist/async.js:2220:16)
    at Object.awaitable(eachLimit) (./node_modules/async/dist/async.js:208:32)
    at HoneybadgerSourceMapPlugin.uploadSourceMaps (./node_modules/honeybadger-webpack/dist/HoneybadgerSourceMapPlugin.js:184:23)
    at HoneybadgerSourceMapPlugin.afterEmit (./node_modules/honeybadger-webpack/dist/HoneybadgerSourceMapPlugin.js:81:12)
    at AsyncSeriesHook.eval [as callAsync] (eval at create (./node_modules/tapable/lib/HookCodeFactory.js:33:10), <anonymous>:7:1)
    at AsyncSeriesHook.lazyCompileHook (./node_modules/tapable/lib/Hook.js:154:20)
    at ./node_modules/webpack/lib/Compiler.js:482:27
    at ./node_modules/neo-async/async.js:2818:7
    at done (./node_modules/neo-async/async.js:3522:9)
error Command failed with exit code 1.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.

futureEmitAssets = true will be forced in Webpack 5. create-react-app 3.x already configures futureEmitAssets = true.

Fortunately, webpack 4.41 introduced another hook to retrieve emitted assets. This PR uses this functionality to keep asset contents accessible.

Related PRs

Todos

• Tests
• Documentation
• Changelog Entry (unreleased)

Steps to Test or Reproduce