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

309 lines
11 KiB
JavaScript

/*
MIT License http://www.opensource.org/licenses/mit-license.php
Author Tobias Koppers @sokra
*/
"use strict";
const HarmonyImportDependency = require("../dependencies/HarmonyImportDependency");
const ModuleHotAcceptDependency = require("../dependencies/ModuleHotAcceptDependency");
const ModuleHotDeclineDependency = require("../dependencies/ModuleHotDeclineDependency");
const ConcatenatedModule = require("./ConcatenatedModule");
const HarmonyExportImportedSpecifierDependency = require("../dependencies/HarmonyExportImportedSpecifierDependency");
const HarmonyCompatibilityDependency = require("../dependencies/HarmonyCompatibilityDependency");
function formatBailoutReason(msg) {
return "ModuleConcatenation bailout: " + msg;
}
class ModuleConcatenationPlugin {
constructor(options) {
if(typeof options !== "object") options = {};
this.options = options;
}
apply(compiler) {
compiler.plugin("compilation", (compilation, params) => {
params.normalModuleFactory.plugin("parser", (parser, parserOptions) => {
parser.plugin("call eval", () => {
parser.state.module.meta.hasEval = true;
});
});
const bailoutReasonMap = new Map();
function setBailoutReason(module, reason) {
bailoutReasonMap.set(module, reason);
module.optimizationBailout.push(typeof reason === "function" ? (rs) => formatBailoutReason(reason(rs)) : formatBailoutReason(reason));
}
function getBailoutReason(module, requestShortener) {
const reason = bailoutReasonMap.get(module);
if(typeof reason === "function") return reason(requestShortener);
return reason;
}
compilation.plugin("optimize-chunk-modules", (chunks, modules) => {
const relevantModules = [];
const possibleInners = new Set();
for(const module of modules) {
// Only harmony modules are valid for optimization
if(!module.meta || !module.meta.harmonyModule || !module.dependencies.some(d => d instanceof HarmonyCompatibilityDependency)) {
setBailoutReason(module, "Module is not an ECMAScript module");
continue;
}
// Because of variable renaming we can't use modules with eval
if(module.meta && module.meta.hasEval) {
setBailoutReason(module, "Module uses eval()");
continue;
}
// Exports must be known (and not dynamic)
if(!Array.isArray(module.providedExports)) {
setBailoutReason(module, "Module exports are unknown");
continue;
}
// Using dependency variables is not possible as this wraps the code in a function
if(module.variables.length > 0) {
setBailoutReason(module, `Module uses injected variables (${module.variables.map(v => v.name).join(", ")})`);
continue;
}
// Hot Module Replacement need it's own module to work correctly
if(module.dependencies.some(dep => dep instanceof ModuleHotAcceptDependency || dep instanceof ModuleHotDeclineDependency)) {
setBailoutReason(module, "Module uses Hot Module Replacement");
continue;
}
relevantModules.push(module);
// Module must not be the entry points
if(module.getChunks().some(chunk => chunk.entryModule === module)) {
setBailoutReason(module, "Module is an entry point");
continue;
}
// Module must only be used by Harmony Imports
const nonHarmonyReasons = module.reasons.filter(reason => !(reason.dependency instanceof HarmonyImportDependency));
if(nonHarmonyReasons.length > 0) {
const importingModules = new Set(nonHarmonyReasons.map(r => r.module));
const importingModuleTypes = new Map(Array.from(importingModules).map(m => [m, new Set(nonHarmonyReasons.filter(r => r.module === m).map(r => r.dependency.type).sort())]));
setBailoutReason(module, (requestShortener) => {
const names = Array.from(importingModules).map(m => `${m.readableIdentifier(requestShortener)} (referenced with ${Array.from(importingModuleTypes.get(m)).join(", ")})`).sort();
return `Module is referenced from these modules with unsupported syntax: ${names.join(", ")}`;
});
continue;
}
possibleInners.add(module);
}
// sort by depth
// modules with lower depth are more likely suited as roots
// this improves performance, because modules already selected as inner are skipped
relevantModules.sort((a, b) => {
return a.depth - b.depth;
});
const concatConfigurations = [];
const usedAsInner = new Set();
for(const currentRoot of relevantModules) {
// when used by another configuration as inner:
// the other configuration is better and we can skip this one
if(usedAsInner.has(currentRoot))
continue;
// create a configuration with the root
const currentConfiguration = new ConcatConfiguration(currentRoot);
// cache failures to add modules
const failureCache = new Map();
// try to add all imports
for(const imp of this.getImports(currentRoot)) {
const problem = this.tryToAdd(currentConfiguration, imp, possibleInners, failureCache);
if(problem) {
failureCache.set(imp, problem);
currentConfiguration.addWarning(imp, problem);
}
}
if(!currentConfiguration.isEmpty()) {
concatConfigurations.push(currentConfiguration);
for(const module of currentConfiguration.modules) {
if(module !== currentConfiguration.rootModule)
usedAsInner.add(module);
}
}
}
// HACK: Sort configurations by length and start with the longest one
// to get the biggers groups possible. Used modules are marked with usedModules
// TODO: Allow to reuse existing configuration while trying to add dependencies.
// This would improve performance. O(n^2) -> O(n)
concatConfigurations.sort((a, b) => {
return b.modules.size - a.modules.size;
});
const usedModules = new Set();
for(const concatConfiguration of concatConfigurations) {
if(usedModules.has(concatConfiguration.rootModule))
continue;
const newModule = new ConcatenatedModule(concatConfiguration.rootModule, Array.from(concatConfiguration.modules));
concatConfiguration.sortWarnings();
for(const warning of concatConfiguration.warnings) {
newModule.optimizationBailout.push((requestShortener) => {
const reason = getBailoutReason(warning[0], requestShortener);
const reasonWithPrefix = reason ? ` (<- ${reason})` : "";
if(warning[0] === warning[1])
return formatBailoutReason(`Cannot concat with ${warning[0].readableIdentifier(requestShortener)}${reasonWithPrefix}`);
else
return formatBailoutReason(`Cannot concat with ${warning[0].readableIdentifier(requestShortener)} because of ${warning[1].readableIdentifier(requestShortener)}${reasonWithPrefix}`);
});
}
const chunks = concatConfiguration.rootModule.getChunks();
for(const m of concatConfiguration.modules) {
usedModules.add(m);
chunks.forEach(chunk => chunk.removeModule(m));
}
chunks.forEach(chunk => {
chunk.addModule(newModule);
newModule.addChunk(chunk);
if(chunk.entryModule === concatConfiguration.rootModule)
chunk.entryModule = newModule;
});
compilation.modules.push(newModule);
newModule.reasons.forEach(reason => reason.dependency.module = newModule);
newModule.dependencies.forEach(dep => {
if(dep.module) {
dep.module.reasons.forEach(reason => {
if(reason.dependency === dep)
reason.module = newModule;
});
}
});
}
compilation.modules = compilation.modules.filter(m => !usedModules.has(m));
});
});
}
getImports(module) {
return Array.from(new Set(module.dependencies
// Only harmony Dependencies
.filter(dep => dep instanceof HarmonyImportDependency && dep.module)
// Dependencies are simple enough to concat them
.filter(dep => {
return !module.dependencies.some(d =>
d instanceof HarmonyExportImportedSpecifierDependency &&
d.importDependency === dep &&
!d.id &&
!Array.isArray(dep.module.providedExports)
);
})
// Take the imported module
.map(dep => dep.module)
));
}
tryToAdd(config, module, possibleModules, failureCache) {
const cacheEntry = failureCache.get(module);
if(cacheEntry) {
return cacheEntry;
}
// Already added?
if(config.has(module)) {
return null;
}
// Not possible to add?
if(!possibleModules.has(module)) {
failureCache.set(module, module); // cache failures for performance
return module;
}
// module must be in the same chunks
if(!config.rootModule.hasEqualsChunks(module)) {
failureCache.set(module, module); // cache failures for performance
return module;
}
// Clone config to make experimental changes
const testConfig = config.clone();
// Add the module
testConfig.add(module);
// Every module which depends on the added module must be in the configuration too.
for(const reason of module.reasons) {
const problem = this.tryToAdd(testConfig, reason.module, possibleModules, failureCache);
if(problem) {
failureCache.set(module, problem); // cache failures for performance
return problem;
}
}
// Eagerly try to add imports too if possible
for(const imp of this.getImports(module)) {
const problem = this.tryToAdd(testConfig, imp, possibleModules, failureCache);
if(problem) {
config.addWarning(module, problem);
}
}
// Commit experimental changes
config.set(testConfig);
return null;
}
}
class ConcatConfiguration {
constructor(rootModule) {
this.rootModule = rootModule;
this.modules = new Set([rootModule]);
this.warnings = new Map();
}
add(module) {
this.modules.add(module);
}
has(module) {
return this.modules.has(module);
}
isEmpty() {
return this.modules.size === 1;
}
addWarning(module, problem) {
this.warnings.set(module, problem);
}
sortWarnings() {
this.warnings = new Map(Array.from(this.warnings).sort((a, b) => {
const ai = a[0].identifier();
const bi = b[0].identifier();
if(ai < bi) return -1;
if(ai > bi) return 1;
return 0;
}));
}
clone() {
const clone = new ConcatConfiguration(this.rootModule);
for(const module of this.modules)
clone.add(module);
for(const pair of this.warnings)
clone.addWarning(pair[0], pair[1]);
return clone;
}
set(config) {
this.rootModule = config.rootModule;
this.modules = new Set(config.modules);
this.warnings = new Map(config.warnings);
}
}
module.exports = ModuleConcatenationPlugin;