lepu-test-platform-web/node_modules/webpack/lib/optimize/AggressiveMergingPlugin.js

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/*
MIT License http://www.opensource.org/licenses/mit-license.php
Author Tobias Koppers @sokra
*/
"use strict";
class AggressiveMergingPlugin {
constructor(options) {
if(options !== undefined && typeof options !== "object" || Array.isArray(options)) {
throw new Error("Argument should be an options object. To use defaults, pass in nothing.\nFor more info on options, see https://webpack.js.org/plugins/");
}
this.options = options || {};
}
apply(compiler) {
const options = this.options;
const minSizeReduce = options.minSizeReduce || 1.5;
function getParentsWeight(chunk) {
return chunk.parents.map((p) => {
return p.isInitial() ? options.entryChunkMultiplicator || 10 : 1;
}).reduce((a, b) => {
return a + b;
}, 0);
}
compiler.plugin("this-compilation", (compilation) => {
compilation.plugin("optimize-chunks-advanced", (chunks) => {
let combinations = [];
chunks.forEach((a, idx) => {
if(a.isInitial()) return;
for(let i = 0; i < idx; i++) {
const b = chunks[i];
if(b.isInitial()) continue;
combinations.push({
a,
b,
improvement: undefined
});
}
});
combinations.forEach((pair) => {
const a = pair.b.size({
chunkOverhead: 0
});
const b = pair.a.size({
chunkOverhead: 0
});
const ab = pair.b.integratedSize(pair.a, {
chunkOverhead: 0
});
let newSize;
if(ab === false) {
pair.improvement = false;
return;
} else if(options.moveToParents) {
const aOnly = ab - b;
const bOnly = ab - a;
const common = a + b - ab;
newSize = common + getParentsWeight(pair.b) * aOnly + getParentsWeight(pair.a) * bOnly;
} else {
newSize = ab;
}
pair.improvement = (a + b) / newSize;
});
combinations = combinations.filter((pair) => {
return pair.improvement !== false;
});
combinations.sort((a, b) => {
return b.improvement - a.improvement;
});
const pair = combinations[0];
if(!pair) return;
if(pair.improvement < minSizeReduce) return;
if(options.moveToParents) {
const commonModules = pair.b.modules.filter((m) => {
return pair.a.modules.indexOf(m) >= 0;
});
const aOnlyModules = pair.b.modules.filter((m) => {
return commonModules.indexOf(m) < 0;
});
const bOnlyModules = pair.a.modules.filter((m) => {
return commonModules.indexOf(m) < 0;
});
aOnlyModules.forEach((m) => {
pair.b.removeModule(m);
m.removeChunk(pair.b);
pair.b.parents.forEach((c) => {
c.addModule(m);
m.addChunk(c);
});
});
bOnlyModules.forEach((m) => {
pair.a.removeModule(m);
m.removeChunk(pair.a);
pair.a.parents.forEach((c) => {
c.addModule(m);
m.addChunk(c);
});
});
}
if(pair.b.integrate(pair.a, "aggressive-merge")) {
chunks.splice(chunks.indexOf(pair.a), 1);
return true;
}
});
});
}
}
module.exports = AggressiveMergingPlugin;