[JavaScript知识库]vue-cli源码梳理，进行中。。。

//D:testWEB/vue-demo/node_modules/webpack/lib/Compilation.js
class Compilation extends Tapable{
constructor(compiler) {
		super();

		/** @type {string=} */
		this.name = undefined;
		/** @type {Compiler} */
		this.compiler = compiler;
		this.resolverFactory = compiler.resolverFactory;
		this.inputFileSystem = compiler.inputFileSystem;
		this.requestShortener = compiler.requestShortener;

		const options = compiler.options;
		this.options = options;
	
	}

	addModuleDependencies(module,dependencies,bail,cacheGroup,recursive,callback) {
		asyncLib.forEach(
			dependencies,
			(item, callback) => {
				semaphore.acquire(() => {
					factory.create(
						{
							contextInfo: {
								issuer: module.nameForCondition && module.nameForCondition(),
								compiler: this.compiler.name
							},
							resolveOptions: module.resolveOptions,
							context: module.context,
							dependencies: dependencies
						},
						(err, dependentModule) => {
							let afterFactory;
							if (addModuleResult.build) {
								// 从这里进入 1111111111111111111111111111111
								this.buildModule(
									dependentModule,
									isOptional(),
									module,
									dependencies,
									err => {
										if (err) {
											semaphore.release();
											return errorOrWarningAndCallback(err);
										}

										if (currentProfile) {
											const afterBuilding = Date.now();
											currentProfile.building = afterBuilding - afterFactory;
										}

										semaphore.release();
										afterBuild();
									}
								);
							} else {
								semaphore.release();
								this.waitForBuildingFinished(dependentModule, afterBuild);
							}
						}
					);
				});
			},
			err => {
				if (err) {
					// eslint-disable-next-line no-self-assign
					err.stack = err.stack;
					return callback(err);
				}

				return process.nextTick(callback);
			}
		);
	}
	// 2222222222222222222222
	buildModule(module, optional, origin, dependencies, thisCallback) {
		
		module.build(
			this.options,
			this,
			this.resolverFactory.get("normal", module.resolveOptions),
			this.inputFileSystem,
			error => {
				const errors = module.errors;
				for (let indexError = 0; indexError < errors.length; indexError++) {
					const err = errors[indexError];
					err.origin = origin;
					err.dependencies = dependencies;
					if (optional) {
						this.warnings.push(err);
					} else {
						this.errors.push(err);
					}
				}

				const warnings = module.warnings;
				for (
					let indexWarning = 0;
					indexWarning < warnings.length;
					indexWarning++
				) {
					const war = warnings[indexWarning];
					war.origin = origin;
					war.dependencies = dependencies;
					this.warnings.push(war);
				}
				const originalMap = module.dependencies.reduce((map, v, i) => {
					map.set(v, i);
					return map;
				}, new Map());
				module.dependencies.sort((a, b) => {
					const cmp = compareLocations(a.loc, b.loc);
					if (cmp) return cmp;
					return originalMap.get(a) - originalMap.get(b);
				});
				if (error) {
					this.hooks.failedModule.call(module, error);
					return callback(error);
				}
				this.hooks.succeedModule.call(module);
				return callback();
			}
		);
	}
}

//D:\testWEB\vue-demo\node_modules\webpack\lib\NormalModule.js
class NormalModule extends Module{
	//333333333333333333
	build(options, compilation, resolver, fs, callback) {
		//444444444444444444
		return this.doBuild(options, compilation, resolver, fs, err => {
			this._cachedSources.clear();

			try {
				const result = this.parser.parse(
					this._ast || this._source.source(),
					{
						current: this,
						module: this,
						compilation: compilation,
						options: options
					},
					(err, result) => {
						if (err) {
							handleParseError(err);
						} else {
							handleParseResult(result);
						}
					}
				);
				if (result !== undefined) {
					// parse is sync
					handleParseResult(result);
				}
			} catch (e) {
				handleParseError(e);
			}
		});
	}
	//5555555555555555555
	doBuild(options, compilation, resolver, fs, callback) {
		const loaderContext = this.createLoaderContext(
			resolver,
			options,
			compilation,
			fs
		);
		// 66666666666666666666666666
		runLoaders(
			{
				resource: this.resource,
				loaders: this.loaders,
				context: loaderContext,
				readResource: fs.readFile.bind(fs)
			},
			(err, result) => {
				if (result) {
					this.buildInfo.cacheable = result.cacheable;
					this.buildInfo.fileDependencies = new Set(result.fileDependencies);
					this.buildInfo.contextDependencies = new Set(
						result.contextDependencies
					);
				}

				if (err) {
					if (!(err instanceof Error)) {
						err = new NonErrorEmittedError(err);
					}
					const currentLoader = this.getCurrentLoader(loaderContext);
					const error = new ModuleBuildError(this, err, {
						from:
							currentLoader &&
							compilation.runtimeTemplate.requestShortener.shorten(
								currentLoader.loader
							)
					});
					return callback(error);
				}

				const resourceBuffer = result.resourceBuffer;
				const source = result.result[0];
				const sourceMap = result.result.length >= 1 ? result.result[1] : null;
				const extraInfo = result.result.length >= 2 ? result.result[2] : null;

				if (!Buffer.isBuffer(source) && typeof source !== "string") {
					const currentLoader = this.getCurrentLoader(loaderContext, 0);
					const err = new Error(
						`Final loader (${
							currentLoader
								? compilation.runtimeTemplate.requestShortener.shorten(
										currentLoader.loader
								  )
								: "unknown"
						}) didn't return a Buffer or String`
					);
					const error = new ModuleBuildError(this, err);
					return callback(error);
				}

				this._source = this.createSource(
					this.binary ? asBuffer(source) : asString(source),
					resourceBuffer,
					sourceMap
				);
				this._sourceSize = null;
				this._ast =
					typeof extraInfo === "object" &&
					extraInfo !== null &&
					extraInfo.webpackAST !== undefined
						? extraInfo.webpackAST
						: null;
				return callback();
			}
		);
	}
}

D:\testWEB\vue-demo\node_modules\loader-runner\lib\LoaderRunner.js
//8888888888888888
function iteratePitchingLoaders(options, loaderContext, callback) {
	// abort after last loader
	if(loaderContext.loaderIndex >= loaderContext.loaders.length)
		return processResource(options, loaderContext, callback);

	var currentLoaderObject = loaderContext.loaders[loaderContext.loaderIndex];

	// iterate
	if(currentLoaderObject.pitchExecuted) {
		loaderContext.loaderIndex++;
		return iteratePitchingLoaders(options, loaderContext, callback);
	}

	// load loader module
	//999999999999999999
	loadLoader(currentLoaderObject, function(err) {
		if(err) {
			loaderContext.cacheable(false);
			return callback(err);
		}
		var fn = currentLoaderObject.pitch;
		currentLoaderObject.pitchExecuted = true;
		if(!fn) return iteratePitchingLoaders(options, loaderContext, callback);
		//第12
		runSyncOrAsync(
			fn,
			loaderContext, [loaderContext.remainingRequest, loaderContext.previousRequest, currentLoaderObject.data = {}],
			function(err) {
				if(err) return callback(err);
				var args = Array.prototype.slice.call(arguments, 1);
				if(args.length > 0) {
					loaderContext.loaderIndex--;
					iterateNormalLoaders(options, loaderContext, args, callback);
				} else {
					iteratePitchingLoaders(options, loaderContext, callback);
				}
			}
		);
	});
}
//第13
function runSyncOrAsync(fn, context, args, callback) {
	var isSync = true;
	var isDone = false;
	var isError = false; // internal error
	var reportedError = false;
	context.async = function async() {
		if(isDone) {
			if(reportedError) return; // ignore
			throw new Error("async(): The callback was already called.");
		}
		isSync = false;
		return innerCallback;
	};
	var innerCallback = context.callback = function() {
		if(isDone) {
			if(reportedError) return; // ignore
			throw new Error("callback(): The callback was already called.");
		}
		isDone = true;
		isSync = false;
		try {
			callback.apply(null, arguments);
		} catch(e) {
			isError = true;
			throw e;
		}
	};
	try {
		var result = (function LOADER_EXECUTION() {
			return fn.apply(context, args);
		}());
		if(isSync) {
			isDone = true;
			if(result === undefined)
				return callback();
			if(result && typeof result === "object" && typeof result.then === "function") {
				return result.then(function(r) {
					callback(null, r);
				}, callback);
			}
			return callback(null, result);
		}
	} catch(e) {
		if(isError) throw e;
		if(isDone) {
			// loader is already "done", so we cannot use the callback function
			// for better debugging we print the error on the console
			if(typeof e === "object" && e.stack) console.error(e.stack);
			else console.error(e);
			return;
		}
		isDone = true;
		reportedError = true;
		callback(e);
	}

}

exports.runLoaders = function runLoaders(options, callback) {
	// read options
	var resource = options.resource || "";
	var loaders = options.loaders || [];
	var loaderContext = options.context || {};
	var readResource = options.readResource || readFile;

	// execution state
	var requestCacheable = true;
	var fileDependencies = [];
	var contextDependencies = [];

	// prepare loader objects
	loaders = loaders.map(createLoaderObject);

	loaderContext.context = contextDirectory;
	loaderContext.loaderIndex = 0;
	loaderContext.loaders = loaders;
	loaderContext.resourcePath = resourcePath;
	loaderContext.resourceQuery = resourceQuery;
	loaderContext.async = null;
	loaderContext.callback = null;
	loaderContext.cacheable = function cacheable(flag) {
		if(flag === false) {
			requestCacheable = false;
		}
	};
	loaderContext.dependency = loaderContext.addDependency = function addDependency(file) {
		fileDependencies.push(file);
	};
	loaderContext.addContextDependency = function addContextDependency(context) {
		contextDependencies.push(context);
	};
	loaderContext.getDependencies = function getDependencies() {
		return fileDependencies.slice();
	};
	loaderContext.getContextDependencies = function getContextDependencies() {
		return contextDependencies.slice();
	};
	loaderContext.clearDependencies = function clearDependencies() {
		fileDependencies.length = 0;
		contextDependencies.length = 0;
		requestCacheable = true;
	};
	
	// finish loader context
	if(Object.preventExtensions) {
		Object.preventExtensions(loaderContext);
	}

	var processOptions = {
		resourceBuffer: null,
		readResource: readResource
	};
	//777777777777777777
	iteratePitchingLoaders(processOptions, loaderContext, function(err, result) {
		if(err) {
			return callback(err, {
				cacheable: requestCacheable,
				fileDependencies: fileDependencies,
				contextDependencies: contextDependencies
			});
		}
		callback(null, {
			result: result,
			resourceBuffer: processOptions.resourceBuffer,
			cacheable: requestCacheable,
			fileDependencies: fileDependencies,
			contextDependencies: contextDependencies
		});
	});
};

//D:\testWEB\vue-demo\node_modules\loader-runner\lib\LoaderRunner.js
//1010101010
module.exports = function loadLoader(loader, callback) {
	if(typeof System === "object" && typeof System.import === "function") {
		System.import(loader.path).catch(callback).then(function(module) {
			loader.normal = typeof module === "function" ? module : module.default;
			loader.pitch = module.pitch;
			loader.raw = module.raw;
			if(typeof loader.normal !== "function" && typeof loader.pitch !== "function") {
				return callback(new LoaderLoadingError(
					"Module '" + loader.path + "' is not a loader (must have normal or pitch function)"
				));
			}
			callback();
		});
	} else {
		try {
			var module = require(loader.path);
		} catch(e) {
			// it is possible for node to choke on a require if the FD descriptor
			// limit has been reached. give it a chance to recover.
			if(e instanceof Error && e.code === "EMFILE") {
				var retry = loadLoader.bind(null, loader, callback);
				if(typeof setImmediate === "function") {
					// node >= 0.9.0
					return setImmediate(retry);
				} else {
					// node < 0.9.0
					return process.nextTick(retry);
				}
			}
			return callback(e);
		}
		if(typeof module !== "function" && typeof module !== "object") {
			return callback(new LoaderLoadingError(
				"Module '" + loader.path + "' is not a loader (export function or es6 module)"
			));
		}
		loader.normal = typeof module === "function" ? module : module.default;
		loader.pitch = module.pitch;
		loader.raw = module.raw;
		if(typeof loader.normal !== "function" && typeof loader.pitch !== "function") {
			return callback(new LoaderLoadingError(
				"Module '" + loader.path + "' is not a loader (must have normal or pitch function)"
			));
		}
		// 第11
		callback();
	}
};