异步回调的返回值（在单元测试中）

Question

我正在尝试对我的 node.js 项目进行 jasmine-node 单元测试。我需要获取一个文件路径数组，然后将该数组传递给单元测试。但是，由于这是异步的，所以我必须使用回调，并且无法返回数组。我不知道如何将检索到的数组发送到单元测试。

这是我的代码：

module.exports = {
    results: [],
    walk: function(){
        var nodeDir = require( "node-dir" );
        nodeDir.files( __dirname + "/public/img", function( err, files ){
            if ( err ){ throw err; }    
            getData( files );
        } );  
    },
    getData: function( files ){
        console.log( files );
        results = files;
    }
};

这是我的单元测试：

var gallery = require( "./server" );

describe( "Gallery", function() {
    var picArray = [
        "/gallery/public/img/dir1/lizard-248705_1280.jpg",
        "/gallery/public/img/dir1/loch-ness-151851_1280.png",
        "/gallery/public/img/dir1/sand-lizard-63185_1280.jpg",
        "/gallery/public/img/dir1/stegosaurus-24752_1280.png"];

    it( "walks the images directory", function(){
        expect(gallery.walk()).toEqual(picArray);
    });
});

Answer 1

这样您就可以将数组发回。尚未测试，但应该可以。

 module.exports = {
      results: [],
      walk: function(callback){ //Added callback argument
        var nodeDir = require( "node-dir" );
        nodeDir.files( __dirname + "/public/img", function( err, files ){
            if ( err ){ throw err; }    
            callback(files);
        } );  
      }
 };

单元测试：

var gallery = require( "./server" );

describe( "Gallery", function() {
    var picArray = [
        "/gallery/public/img/dir1/lizard-248705_1280.jpg",
        "/gallery/public/img/dir1/loch-ness-151851_1280.png",
        "/gallery/public/img/dir1/sand-lizard-63185_1280.jpg",
        "/gallery/public/img/dir1/stegosaurus-24752_1280.png"];

    it( "walks the images directory", function(done){
        gallery.walk(function(files){ //Pass callback to walk
            //Your code here
            done(); //ends the async test
        });
    });
});