node_modules/enhanced-resolve/lib/DirectoryExistsPlugin.js

/*
	MIT License http://www.opensource.org/licenses/mit-license.php
	Author Tobias Koppers @sokra
*/
"use strict";

module.exports = class DirectoryExistsPlugin {
	constructor(source, target) {
		this.source = source;
		this.target = target;
	}

	apply(resolver) {
		const target = resolver.ensureHook(this.target);
		resolver
			.getHook(this.source)
			.tapAsync(
				"DirectoryExistsPlugin",
				(request, resolveContext, callback) => {
					const fs = resolver.fileSystem;
					const directory = request.path;
					fs.stat(directory, (err, stat) => {
						if (err || !stat) {
							if (resolveContext.missing) resolveContext.missing.add(directory);
							if (resolveContext.log)
								resolveContext.log(directory + " doesn't exist");
							return callback();
						}
						if (!stat.isDirectory()) {
							if (resolveContext.missing) resolveContext.missing.add(directory);
							if (resolveContext.log)
								resolveContext.log(directory + " is not a directory");
							return callback();
						}
						resolver.doResolve(
							target,
							request,
							"existing directory",
							resolveContext,
							callback
						);
					});
				}
			);
	}
};