name : FileExistsPlugin.js /* MIT License http://www.opensource.org/licenses/mit-license.php Author Tobias Koppers @sokra */ "use strict"; /** @typedef {import("./Resolver")} Resolver */ /** @typedef {import("./Resolver").ResolveStepHook} ResolveStepHook */ module.exports = class FileExistsPlugin { /** * @param {string | ResolveStepHook} source source * @param {string | ResolveStepHook} target target */ constructor(source, target) { this.source = source; this.target = target; } /** * @param {Resolver} resolver the resolver * @returns {void} */ apply(resolver) { const target = resolver.ensureHook(this.target); const fs = resolver.fileSystem; resolver .getHook(this.source) .tapAsync("FileExistsPlugin", (request, resolveContext, callback) => { const file = request.path; if (!file) return callback(); fs.stat(file, (err, stat) => { if (err || !stat) { if (resolveContext.missingDependencies) resolveContext.missingDependencies.add(file); if (resolveContext.log) resolveContext.log(file + " doesn't exist"); return callback(); } if (!stat.isFile()) { if (resolveContext.missingDependencies) resolveContext.missingDependencies.add(file); if (resolveContext.log) resolveContext.log(file + " is not a file"); return callback(); } if (resolveContext.fileDependencies) resolveContext.fileDependencies.add(file); resolver.doResolve( target, request, "existing file: " + file, resolveContext, callback ); }); }); } };