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Webpack 5.beta.11: HMR error Cannot read property 'getModuleIndex2' of undefined

See original GitHub issue

Operating System:
Node Version: 13.3
NPM Version: 6.13.1
webpack Version: 5.0.0-beta.11
mini-css-extract-plugin Version: 0.9

HMR code

{
                        loader: MiniCssExtractPlugin.loader,
                        options: {
                            publicPath: '../',
                            sourceMap: CreateSourceMap,
                            hmr: watchMode,
                            reloadAll: true,
                        },
                    },

Expected Behavior

Run webpack in watchmode with HMR
compile css, no issue
rerun, no issue 😃

Actual Behavior

Run webpack in watchmode with HMR
compile css, no issue
rerun, issue 😦

TypeError: Cannot read property 'getModuleIndex2' of undefined at MiniCssExtractPlugin.renderContentAsset ([...]/node_modules/mini-css-extract-plugin/dist/index.js:301:27)

It seems that getModuleIndex2 is deprecated in webpack 5. I don’t know if this plugin is already compatible. If needed I can create a repo with minimal code.

Issue Analytics

State:
Created 4 years ago
Reactions:4
Comments:39 (10 by maintainers)

Top GitHub Comments

6reactions

slightlyfaultycommented, Aug 27, 2020

I tried out the update, but seeing a different error now. Hope it helps.

TypeError: Cannot read property 'getModulePostOrderIndex' of undefined
    at MiniCssExtractPlugin.renderContentAsset (/node_modules/mini-css-extract-plugin/dist/index.js:384:26)
    at Object.render (/node_modules/mini-css-extract-plugin/dist/index.js:225:34)
    at /node_modules/webpack/lib/HotModuleReplacementPlugin.js:488:32
    at Hook.eval [as callAsync] (eval at create (/node_modules/tapable/lib/HookCodeFactory.js:33:10), <anonymous>:9:1)
    at Hook.CALL_ASYNC_DELEGATE [as _callAsync] (/node_modules/tapable/lib/Hook.js:18:14)
    at cont (/node_modules/webpack/lib/Compilation.js:1975:33)
    at /node_modules/webpack/lib/Compilation.js:2013:9
    at /node_modules/neo-async/async.js:2830:7
    at Object.each (/node_modules/neo-async/async.js:2850:39)
    at Compilation.createChunkAssets (/node_modules/webpack/lib/Compilation.js:2969:12)

Using the latest webpack@5.0.0-beta.28

6reactions

slightlyfaultycommented, Jun 22, 2020

Still same issue in webpack@5.0.0-beta.18.

This is a show-stopper bug completely preventing HMR with MiniCssExtractPlugin in Webpack 5. Please give this some attention 🙏

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