Mini-css-extract-plugin: [Optimization request] Remove empty "modules"

[Andarist]

When using this plugin we might end up with something like this:

Click

// 54:
// (function(module, exports, __webpack_require__) {

// extracted by mini-css-extract-plugin

/*/ }),

// 92:
// (function(module, exports, __webpack_require__) {

// extracted by mini-css-extract-plugin

/*/ }),

// 93:
// (function(module, exports, __webpack_require__) {

// extracted by mini-css-extract-plugin

/*/ }),

// 94:
// (function(module, exports, __webpack_require__) {

// extracted by mini-css-extract-plugin

/*/ }),

// 95:
// (function(module, exports, __webpack_require__) {

// extracted by mini-css-extract-plugin

/*/ }),

// 96:
// (function(module, exports, __webpack_require__) {

// extracted by mini-css-extract-plugin

/*/ }),

// 97:
// (function(module, exports, __webpack_require__) {

// extracted by mini-css-extract-plugin

/*/ }),

// 98:
// (function(module, exports, __webpack_require__) {

// extracted by mini-css-extract-plugin

/*/ }),

Seems like this could be optimized away - i know that probably minifier + gzip makes this kinda cheap, but parsing costs add up and it would be always good to strive for less code in such cases.

[alexander-akait]

Please provide minimum reproducible test repo, it should be removed by webpack

[Andarist]

I've somehow missed your reply. Gonna try to prepare slimmed down repro for this.

[irudoy]

@evilebottnawi minimum reproducible test repo: https://github.com/irudoy/webpack-mceplugin-empty-repro

[irudoy]

@evilebottnawi any thoughts?

[alexander-akait]

@irudoy sorry, some busy, but you can send a PR with implementation this feature :+1:

[irudoy]

@evilebottnawi I experimented a bit, but with no luck. Can you point out how to achieve this?

[alexander-akait]

@irudoy we solved this problem for extract-text-webpack-plugin (https://github.com/webpack-contrib/extract-text-webpack-plugin/blob/webpack-1/index.js#L280), i think solution is same

[irudoy]

Some results:

entry1: 269 empty modules
entry2: 186 empty modules

with empty modules:
entry1: 49.9 KiB / 14.3 KiB (gzip)
entry2: 15.8 KiB / 4.8 KiB (gzip)

without empty modules:
entry1: 40.4 KiB / 12.1 KiB (gzip)
entry2: 8.8 KiB / 3.3 KiB (gzip)

[alexander-akait]

Great :+1: