116 lines
3.5 KiB
JavaScript
116 lines
3.5 KiB
JavaScript
|
/*
|
||
|
MIT License http://www.opensource.org/licenses/mit-license.php
|
||
|
Author Tobias Koppers @sokra
|
||
|
*/
|
||
|
|
||
|
"use strict";
|
||
|
|
||
|
const { STAGE_BASIC } = require("../OptimizationStages");
|
||
|
const { runtimeEqual } = require("../util/runtime");
|
||
|
|
||
|
/** @typedef {import("../Compiler")} Compiler */
|
||
|
|
||
|
class MergeDuplicateChunksPlugin {
|
||
|
/**
|
||
|
* @param {Compiler} compiler the compiler
|
||
|
* @returns {void}
|
||
|
*/
|
||
|
apply(compiler) {
|
||
|
compiler.hooks.compilation.tap(
|
||
|
"MergeDuplicateChunksPlugin",
|
||
|
compilation => {
|
||
|
compilation.hooks.optimizeChunks.tap(
|
||
|
{
|
||
|
name: "MergeDuplicateChunksPlugin",
|
||
|
stage: STAGE_BASIC
|
||
|
},
|
||
|
chunks => {
|
||
|
const { chunkGraph, moduleGraph } = compilation;
|
||
|
|
||
|
// remember already tested chunks for performance
|
||
|
const notDuplicates = new Set();
|
||
|
|
||
|
// for each chunk
|
||
|
for (const chunk of chunks) {
|
||
|
// track a Set of all chunk that could be duplicates
|
||
|
let possibleDuplicates;
|
||
|
for (const module of chunkGraph.getChunkModulesIterable(chunk)) {
|
||
|
if (possibleDuplicates === undefined) {
|
||
|
// when possibleDuplicates is not yet set,
|
||
|
// create a new Set from chunks of the current module
|
||
|
// including only chunks with the same number of modules
|
||
|
for (const dup of chunkGraph.getModuleChunksIterable(
|
||
|
module
|
||
|
)) {
|
||
|
if (
|
||
|
dup !== chunk &&
|
||
|
chunkGraph.getNumberOfChunkModules(chunk) ===
|
||
|
chunkGraph.getNumberOfChunkModules(dup) &&
|
||
|
!notDuplicates.has(dup)
|
||
|
) {
|
||
|
// delay allocating the new Set until here, reduce memory pressure
|
||
|
if (possibleDuplicates === undefined) {
|
||
|
possibleDuplicates = new Set();
|
||
|
}
|
||
|
possibleDuplicates.add(dup);
|
||
|
}
|
||
|
}
|
||
|
// when no chunk is possible we can break here
|
||
|
if (possibleDuplicates === undefined) break;
|
||
|
} else {
|
||
|
// validate existing possible duplicates
|
||
|
for (const dup of possibleDuplicates) {
|
||
|
// remove possible duplicate when module is not contained
|
||
|
if (!chunkGraph.isModuleInChunk(module, dup)) {
|
||
|
possibleDuplicates.delete(dup);
|
||
|
}
|
||
|
}
|
||
|
// when all chunks has been removed we can break here
|
||
|
if (possibleDuplicates.size === 0) break;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
// when we found duplicates
|
||
|
if (
|
||
|
possibleDuplicates !== undefined &&
|
||
|
possibleDuplicates.size > 0
|
||
|
) {
|
||
|
outer: for (const otherChunk of possibleDuplicates) {
|
||
|
if (otherChunk.hasRuntime() !== chunk.hasRuntime()) continue;
|
||
|
if (chunkGraph.getNumberOfEntryModules(chunk) > 0) continue;
|
||
|
if (chunkGraph.getNumberOfEntryModules(otherChunk) > 0)
|
||
|
continue;
|
||
|
if (!runtimeEqual(chunk.runtime, otherChunk.runtime)) {
|
||
|
for (const module of chunkGraph.getChunkModulesIterable(
|
||
|
chunk
|
||
|
)) {
|
||
|
const exportsInfo = moduleGraph.getExportsInfo(module);
|
||
|
if (
|
||
|
!exportsInfo.isEquallyUsed(
|
||
|
chunk.runtime,
|
||
|
otherChunk.runtime
|
||
|
)
|
||
|
) {
|
||
|
continue outer;
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
// merge them
|
||
|
if (chunkGraph.canChunksBeIntegrated(chunk, otherChunk)) {
|
||
|
chunkGraph.integrateChunks(chunk, otherChunk);
|
||
|
compilation.chunks.delete(otherChunk);
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
// don't check already processed chunks twice
|
||
|
notDuplicates.add(chunk);
|
||
|
}
|
||
|
}
|
||
|
);
|
||
|
}
|
||
|
);
|
||
|
}
|
||
|
}
|
||
|
module.exports = MergeDuplicateChunksPlugin;
|