work.suroh.tk/node_modules/enhanced-resolve/lib/MainFieldPlugin.js

67 lines
1.7 KiB
JavaScript

/*
MIT License http://www.opensource.org/licenses/mit-license.php
Author Tobias Koppers @sokra
*/
"use strict";
const path = require("path");
module.exports = class MainFieldPlugin {
constructor(source, options, target) {
this.source = source;
this.options = options;
this.target = target;
}
apply(resolver) {
const target = resolver.ensureHook(this.target);
resolver
.getHook(this.source)
.tapAsync("MainFieldPlugin", (request, resolveContext, callback) => {
if (request.path !== request.descriptionFileRoot) return callback();
if (request.alreadyTriedMainField === request.descriptionFilePath)
return callback();
const content = request.descriptionFileData;
const filename = path.basename(request.descriptionFilePath);
let mainModule;
const field = this.options.name;
if (Array.isArray(field)) {
let current = content;
for (let j = 0; j < field.length; j++) {
if (current === null || typeof current !== "object") {
current = null;
break;
}
current = current[field[j]];
}
if (typeof current === "string") {
mainModule = current;
}
} else {
if (typeof content[field] === "string") {
mainModule = content[field];
}
}
if (!mainModule) return callback();
if (this.options.forceRelative && !/^\.\.?\//.test(mainModule))
mainModule = "./" + mainModule;
const obj = Object.assign({}, request, {
request: mainModule,
alreadyTriedMainField: request.descriptionFilePath
});
return resolver.doResolve(
target,
obj,
"use " +
mainModule +
" from " +
this.options.name +
" in " +
filename,
resolveContext,
callback
);
});
}
};