[@types/terser-webpack-plugin] Support for webpack 5

[rajzik]

@types/terser-webpack-plugin doesn't support webpack 5 types which are now generated by webpack itself.

node_modules/@types/terser-webpack-plugin/index.d.ts:7:10 - error TS2305: Module '"../../webpack/types"' has no exported member 'Plugin'.

7 import { Plugin } from 'webpack';
           ~~~~~~

• I tried using the @types/terser-webpack-plugin package and had problems.
• I tried using the latest stable version of tsc. https://www.npmjs.com/package/typescript
• Mention the authors (see Definitions by: in index.d.ts) so they can respond.
  • Authors: @Danscho, @peterblazejewicz

[Danscho]

@peterblazejewicz already created a pull request.
Please see: #48794.
This should resolve your issue.

[isellsoap]

I have another error message popping up in the webpack config file, when using terser-webpack-plugin 5.0.0 with webpack 5:

Type 'TerserPlugin' is not assignable to type '"..." | WebpackPluginInstance | ((this: Compiler, compiler: Compiler) => void)'.
  Type 'TerserPlugin' is not assignable to type '(this: Compiler, compiler: Compiler) => void'.
    Type 'TerserPlugin' provides no match for the signature '(this: Compiler, compiler: Compiler): void'.ts(2322)

Anyone else having this issue?

[buschtoens]

From what I can tell the issue is that the latest version of @types/terser-webpack-plugin, even after #48794, still specifies @types/webpack@* as dependency, which resolves to wepack@4.41.21. It seems that this dependency is somehow added implicitly by @DefinitelyTyped, as I can't find it in the package.json. Do we maybe have to add webpack@5 as a dependency to prevent this?

webpack@5 also doesn't export Plugin any more, but e.g. WebpackPluginInstance.

[rajzik]

@buschtoens
#48857
there was same issue with webpack 5.

[echochens]

Have any guys solved the problem？