Const reassignment in production build

Bug report

What is the current behavior?

Webpack generates code using a const variable and then attempts to re-assign it. I suppose this could be due to the vue dependencies I’m using - but this code very much appears to be generated by webpack itself (or at least, half of it is, and then the libraryExport option attempts to overwrite it).

It seems like this shouldn’t be creating a block-scoped variable here at all, and assigning it to the global variable for the named library export.

If the current behavior is a bug, please provide the steps to reproduce.

Repo with minimal reproduction: https://github.com/richinfante/webpack-bug-repro

I’ve disabled the terser plugin in the test repo so output isn’t minified & optimized.

In short, running a production build generates the following code, which yields a syntax error in browsers:

/* harmony default export */ const empty_component = (component.exports);
empty_component = __webpack_exports__.default;

What is the expected behavior?

Webpack shouldn’t generate code that tries to re-assign a const variable.

Other relevant information: webpack version: 5.28.0 Node.js version: v14.16.0 Operating System: Arch Linux (5.11.8-arch1-1) Additional tools: Vue 2.6.12

[sokra]

as workaround: rename your empty_component.vue file to something else.

[alexander-akait]

Marked as critical-bug, we will try to fix it in near future