feat: hmr, compare old locals to invalidate if needed

[goloveychuk]

This PR contains a:

• bugfix
• new feature
• code refactor
• test update
• typo fix
• metadata update

Motivation / Use-Case

This allows self accept css module if locals didn't changed. If changed - propagate.
Inspired by https://github.com/webpack-contrib/style-loader/blob/master/src/index.js#L231
Now new runtime is

// extracted by mini-css-extract-plugin
    if(true) {
      // 1612290403401
      var cssReload = __webpack_require__(/*! ../node_modules/mini-css-extract-plugin/dist/hmr/hotModuleReplacement.js */ "../node_modules/mini-css-extract-plugin/dist/hmr/hotModuleReplacement.js")(module.id, {"publicPath":"","esModule":false,"locals":false});
      var _locals = undefined;
      var isEqualLocals = __webpack_require__(/*! ../node_modules/mini-css-extract-plugin/dist/hmr/isEqualLocals.js */ "../node_modules/mini-css-extract-plugin/dist/hmr/isEqualLocals.js");
      module.hot.dispose(function(data) {
        cssReload();
        data.oldLocals = _locals;
      });
      
      if (!_locals || module.hot.invalidate) {
        if (module.hot.invalidate &&
            module.hot.data &&
            module.hot.data.oldLocals &&
            !isEqualLocals(module.hot.data.oldLocals, _locals)) {
            module.hot.invalidate();
        } else {
          module.hot.accept();
        }
      }
    }
  //# sourceURL=[module]
//# sourceMappingURL=data:applicati

Breaking Changes

Additional Info

[goloveychuk]

@alexander-akait could you please review? Should I fix tests first (look like all of them are code snapshots)

[alexander-akait]

When esModule is true it should be import,

[goloveychuk]

but previously it has

var cssReload = require(${loaderUtils.stringifyRequest(
        context.context,
        path.join(__dirname, 'hmr/hotModuleReplacement.js')

This should be import too?

[alexander-akait]

Yep

[goloveychuk]

fixed

[goloveychuk]

@alexander-akait not sure if webpack module interop will work here, mb need to change to * as $name

[goloveychuk]

printed output,

[goloveychuk]

@alexander-akait could you please review?

[alexander-akait]

@goloveychuk Sorry for delay, apparently I missed a notification somewhere 😞 , do not hesitate to ping me again, do you want to finish this?