用grunt-cmd-xxx构建seajs项目时，使用alias引发的BUG
该BUG与另一个BUG强相关，见：grunt-cmd-transport提取deps[]的BUG
文件
// employee/static/adder.js
define(function (require, exports) {
exports.add = function (a, b) {
return a + b;
}
});
// employee/static/package.js
define(function (require, exports) {
exports.adder = require("adder");
});
// bootstrap/static/main.js
define(function (require) {
var adder = require("employee/static/package").adder;
alert(adder.add(1, 2));
});
transport: {
options: {
paths: [sourceDir],
alias: {
"adder": "employee/static/adder"
}
},
build: {
files: [
{
cwd: sourceDir,
src: ['**/static/**/*.js', '!3rd-lib/*', '**/static/**/*.css'],
dest: buildDir
}
]
}
}
BUG描述
执行grunt transport，main.js提取之后：
define("bootstrap/static/main", [ "employee/static/package", "adder" ], function(require) {
var adder = require("employee/static/package").adder;
alert(adder.add(1, 2));
});
package.js提取后是：
// employee/static/package.js
define("employee/static/package", [ "employee/static/adder" ], function(require, exports) {
exports.adder = require("employee/static/adder");
});
可以看到，package.js提取结果是正确的，而且alias也正确转换。但是受上一个BUG的影响，main.js的提取结果是错误的，不仅把adder也写入了deps[]，而且没有alias转换成功
在链接的文档里介绍过，规避上一个BUG的方法，是在concat中配置include:all。但是现在由于alias转换失败的原因，执行grunt concat时会报错：
Running "concat:build" (concat) task
>> file adder not found
>> file adder-debug not found
然后合并得到的main.js是：
// concated bootstrap/static/main.js
define("bootstrap/static/main", [ "employee/static/package", "adder" ], function(require) {
var adder = require("employee/static/package").adder;
alert(adder.add(1, 2));
});
define("employee/static/package", [ "employee/static/adder" ], function(require, exports) {
exports.adder = require("employee/static/adder");
});
package.js：
// employee/static/package.js
define("employee/static/package", [ "employee/static/adder" ], function(require, exports) {
exports.adder = require("employee/static/adder");
});
define("employee/static/adder", [], function(require, exports) {
exports.add = function(a, b) {
return a + b;
};
});
结果比无效的http请求更严重，因为合并后的main.js已经包含了package，所以不会去请求employee/static/package.js，但是main中并没有adder存在，所以根本调不到adder。同时会发起2个无效的http请求，尝试加载adder.js和employee/static/adder.js
结论
在BUG修复之前：
- 如果使用grunt-cmd-transport和grunt-cmd-concat来构建seajs项目，不要使用alias，使用完整的顶级标识，或者相对标识都可以
- concat设置为include:all，来规避无效http请求的问题