lepu-test-platform-web/node_modules/enhanced-resolve/lib/MainFieldPlugin.js

49 lines
1.4 KiB
JavaScript

/*
MIT License http://www.opensource.org/licenses/mit-license.php
Author Tobias Koppers @sokra
*/
var path = require("path");
function MainFieldPlugin(source, options, target) {
this.source = source;
this.options = options;
this.target = target;
}
module.exports = MainFieldPlugin;
MainFieldPlugin.prototype.apply = function(resolver) {
var target = this.target;
var options = this.options;
resolver.plugin(this.source, function mainField(request, callback) {
if(request.path !== request.descriptionFileRoot) return callback();
var content = request.descriptionFileData;
var filename = path.basename(request.descriptionFilePath);
var mainModule;
var field = options.name;
if(Array.isArray(field)) {
var current = content;
for(var 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(options.forceRelative && !/^\.\.?\//.test(mainModule))
mainModule = "./" + mainModule;
var obj = Object.assign({}, request, {
request: mainModule
});
return resolver.doResolve(target, obj, "use " + mainModule + " from " + options.name + " in " + filename, callback);
});
};