98 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			98 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
/*
 | 
						|
	MIT License http://www.opensource.org/licenses/mit-license.php
 | 
						|
	Author Tobias Koppers @sokra
 | 
						|
*/
 | 
						|
 | 
						|
"use strict";
 | 
						|
 | 
						|
const { STAGE_ADVANCED } = require("../OptimizationStages");
 | 
						|
 | 
						|
/** @typedef {import("../Chunk")} Chunk */
 | 
						|
/** @typedef {import("../Compiler")} Compiler */
 | 
						|
 | 
						|
/**
 | 
						|
 * @typedef {object} AggressiveMergingPluginOptions
 | 
						|
 * @property {number=} minSizeReduce minimal size reduction to trigger merging
 | 
						|
 */
 | 
						|
 | 
						|
const PLUGIN_NAME = "AggressiveMergingPlugin";
 | 
						|
 | 
						|
class AggressiveMergingPlugin {
 | 
						|
	/**
 | 
						|
	 * @param {AggressiveMergingPluginOptions=} options options object
 | 
						|
	 */
 | 
						|
	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 the plugin
 | 
						|
	 * @param {Compiler} compiler the compiler instance
 | 
						|
	 * @returns {void}
 | 
						|
	 */
 | 
						|
	apply(compiler) {
 | 
						|
		const options = this.options;
 | 
						|
		const minSizeReduce = options.minSizeReduce || 1.5;
 | 
						|
 | 
						|
		compiler.hooks.thisCompilation.tap(PLUGIN_NAME, (compilation) => {
 | 
						|
			compilation.hooks.optimizeChunks.tap(
 | 
						|
				{
 | 
						|
					name: PLUGIN_NAME,
 | 
						|
					stage: STAGE_ADVANCED
 | 
						|
				},
 | 
						|
				(chunks) => {
 | 
						|
					const chunkGraph = compilation.chunkGraph;
 | 
						|
					/** @type {{a: Chunk, b: Chunk, improvement: number}[]} */
 | 
						|
					const combinations = [];
 | 
						|
					for (const a of chunks) {
 | 
						|
						if (a.canBeInitial()) continue;
 | 
						|
						for (const b of chunks) {
 | 
						|
							if (b.canBeInitial()) continue;
 | 
						|
							if (b === a) break;
 | 
						|
							if (!chunkGraph.canChunksBeIntegrated(a, b)) {
 | 
						|
								continue;
 | 
						|
							}
 | 
						|
							const aSize = chunkGraph.getChunkSize(b, {
 | 
						|
								chunkOverhead: 0
 | 
						|
							});
 | 
						|
							const bSize = chunkGraph.getChunkSize(a, {
 | 
						|
								chunkOverhead: 0
 | 
						|
							});
 | 
						|
							const abSize = chunkGraph.getIntegratedChunksSize(b, a, {
 | 
						|
								chunkOverhead: 0
 | 
						|
							});
 | 
						|
							const improvement = (aSize + bSize) / abSize;
 | 
						|
							combinations.push({
 | 
						|
								a,
 | 
						|
								b,
 | 
						|
								improvement
 | 
						|
							});
 | 
						|
						}
 | 
						|
					}
 | 
						|
 | 
						|
					combinations.sort((a, b) => b.improvement - a.improvement);
 | 
						|
 | 
						|
					const pair = combinations[0];
 | 
						|
 | 
						|
					if (!pair) return;
 | 
						|
					if (pair.improvement < minSizeReduce) return;
 | 
						|
 | 
						|
					chunkGraph.integrateChunks(pair.b, pair.a);
 | 
						|
					compilation.chunks.delete(pair.a);
 | 
						|
					return true;
 | 
						|
				}
 | 
						|
			);
 | 
						|
		});
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
module.exports = AggressiveMergingPlugin;
 |