Exploring Angular unit testing using Jasmine: Techniques to customize or delete spyOn

Current software versions for AngularJS and Jasmine:

AngularJS v1.2.26

Jasmine v2.2.0

I am facing an issue with a spyOn. When attempting to change or remove its behavior, I encounter the following error message: 

Error: getUpdate has already been spied upon

var data1 = 'foo';
var data2 = 'bar';

describe("a spec with a spy", function(){

    beforeEach(module('app'));

    var $q;

    beforeEach(inject(function(_updateService_, _$q_){
        updateService = _updateService_;

        //Spy on the results of the getUpdate()
        $q = _$q_;
        var deferred = $q.defer();
        deferred.resolve( data1 );
        spyOn(updateService, 'getUpdate').and.returnValue(deferred.promise);

    }));

    describe('attempting to use a different spy here', function() {

        it('should return a different value', function() {

          var deferred = $q.defer();
          deferred.resolve( data2 );
          spyOn(updateService, 'getUpdate'); //ERROR OCCURS HERE
          updateService.getUpdate.and.returnValue(deferred.promise);

          ...

        });
    });

...

If I remove the second spyOn statement, the test does not function properly.

What is the correct approach to resolve this issue?

javascriptangularjsunit-testingjasminekarma-jasmine

Answer №1

You have the ability to simply replace it

updateService.updateData = jasmine.createSpy().and.returnValue(etc)

Answer №2

You have the ability to change the spy's result

    var deferred = $q.defer();
    deferred.resolve( newData );

    var fetchSpy = spyOn(fetchService, 'fetchData').and.returnValue(deferred.promise);



    var newDeferred = $q.defer();
    newDeferred.resolve( updatedData );

    fetchSpy.and.returnValue(newDeferred.promise);

Answer №3

Starting from jasmine version 2.5, you can utilize the global allowRespy() configuration.

jasmine.getEnv().allowRespy(true);

If you need to use spyOn() multiple times without accessing the first spy or when it's not required, this setting will allow that. Just keep in mind that it will give back the previous spy if one is already active.

spyOn(updateService, 'getUpdate').and.returnValue(deferred.promise);
...
spyOn(updateService, 'getUpdate').and.returnValue(deferred.promise);

Answer №4

A more convenient and straightforward method:

updateService.getUpdate.and.returnValue(Observable.of({success:true}));

This will give you the result.

Answer №5

Here is an alternative choice:

(testService.operation as jasmine.Spy).and.returnResponse(output);

Answer №6

The green ticked solution didn't do the trick for me, but I found success with this:

yourAwesomeService.addThing = jasmine.createSpy('fake', function(){}).and.returnValue();

While your jasmine test may pass, be prepared for Typescript errors when running your application if you don't include a random string and an empty function as arguments in createSpy().

Similar questions

If you have not found the answer to your question or you are interested in this topic, then look at other similar questions below or use the search

Display sqllite database information in an HTML view using Ionic 2

After executing a select query against the database, I am able to read the results from the logcat and view the data there. However, I am encountering an issue where the data is not rendering in the HTML view after binding. //data retrieve section db.exec ...

javascriptandroidangularjsionic-frameworkionic2

Restricting the number of characters allowed for text messages and keeping track of the count

I am attempting to implement a character limiter for an html textarea using JavaScript. Additionally, I want to include a total character counter. Unfortunately, the code I have written isn't functioning as expected. Can anyone identify where my mist ...

javascriptjqueryhtmlsms

What is the best way to eliminate the border color on a drop-down menu's bottom border?

I need help removing the border color from a dropdown with the style border-bottom: 1px solid rgba(0, 0, 0, 0.42); After debugging, I discovered that it is originating from the class MuiInput-underline-2593. However, the CSS class MuiInput-underline-2593 ...

javascripthtmlcssreactjsmaterial-ui

Changing a CSS value by incrementing within a loop does not produce the desired result

I experimented with increasing the current value of the 'top' property within a foreach loop. http://jsfiddle.net/fqmnksgL/ var percent = 50; $('div').forEach(function (obj, i) { $(obj).css('top', $(obj).css('top&ap ...

javascriptjqueryzepto

Highlighted option selection in Material UI dropdown using Cypress

Can someone explain how to select Material-UI dropdown options using Cypress? I'm looking for a simple explanation, thanks! ...

javascripttestingautomationmaterial-uicypress

How can you use jQuery to select and manipulate a wildcard href ID?

There are multiple links listed below: <a href="http://www.google.com" id="link01">Google</a> <a href="http://www.yahoo.com" id="link02">Yahoo</a> <a href="http://www.cnn.com" id="link03">CNN</a> <a href="http://www. ...

phpjavascriptjqueryhtml

Guide to uploading images to an s3 bucket using angular and ng2-file-upload

Which part of the code needs to be modified in order to upload images to an S3 bucket? uploader: FileUploader = new FileUploader({ url: URL, disableMultipart: true, formatDataFunctionIsAsync: true, formatDataFunction: async (item) => { ...

angularjsfile-uploadamazon-s3ng2-file-upload

Using cURL instead of AJAX for PHP requests

My current situation may seem simple, but it feels like a tough challenge for me right now. I am attempting to scrape a website that utilizes AJAX calls to retrieve data. This website has a form where you can select options and then click the submit butt ...

phpjavascriptajaxcurlhttp-headers

How can you prevent an element from overflowing when employing window.pageYOffset and using a switch case to alter the background color at specified pixel thresholds?

I want the <body> element's background-color to change every 500px as I scroll down. I've scoured the web for answers, but still can't figure out what's going wrong. Please review the code. However, Firefox Browser indicates that ...

javascripthtmlcss

How to change a date object into a datestring using the TZ format in JavaScript

Here is the input: const date = "06/01/2018" const time = "06:25:00" The desired output format is a string like this: "2018-06-01T00:55:00.000Z". I attempted to create the Date object using const result = new Date(date + time); //outputs an obje ...

javascriptnode.jsreactjsecmascript-6

Comparing the use of jQuery click event with the button to trigger a function that calculates the

Currently, I am grappling with a JQuery function that checks if any checkboxes are ticked within my form. My version of JQuery is v1.10.2. The code functions as expected when triggered by a button, but when I attempt to trigger it with a checkbox within t ...

javascriptjqueryhtmlformscheckbox

Embedded tweets may occasionally lose their borders when viewed on various web browsers

My goal is to showcase a collection of responsive embedded tweets in rows of 2. Here are the key elements of the code that have enabled me to achieve this: HTML <div id="tweets"></div> <script src="https://platform.twitter.com/widgets.js" ...

javascripthtmlcsstwitter

Having difficulties with implementing the throw await syntax in an async express handler in Node.js

const express = require("express"); const expressAsyncHandler = require("express-async-handler"); const app = express(); const func = async () => { return false; }; app.get( "/", expressAsyncHandler(async () => ...

javascriptnode.jsexpress

Display a pop-up when hovering over a layer with react-leaflet

I am attempting to display a popup when hovering over a layer in react leaflet. Utilizing GeoJson to render all layers on the map and onEachFeature() to trigger the popup on hover, I encountered an issue where the popup only appeared upon click, not hover. ...

javascriptcssreactjsleafletreact-leaflet

Locating function definitions in etags using Emacs

I find syntax check in js2-mode to be quite effective. However, there are times when I wish to name a function "delete" or "new" even though it may not be the best practice. Js2-mode often flags this as an error. Is there a way to use built-in keywords as ...

javascriptnode.jsemacssyntaxjslint

Leveraging NPM with Laravel 5 for AngularJS Integration

I am eager to integrate AngularJS with Laravel 5. Since Laravel relies on NPM for installing packages like gulp and laravel-elixir, my initial step was to modify the packages.json file: { "private": true, "devDependencies": { "gulp": "^3.8.8", ...

angularjsnpmlaravel-5

Is there a way for me to access the response from the PHP file I'm calling with Ajax?

I am just starting to explore ajax and jquery, and I recently found a code online that I'm tweaking for my own use. However, I am struggling with how to handle responses from PHP in this context. The current setup involves ajax POSTing to a php page ...

phpjavascriptjqueryhtmlajax

What is the functionality of named function expressions?

After coming across an intriguing example in the book labeled as a "named function expression," I was curious to delve into its mechanics. While the authors mentioned it's not commonly seen, I found it fascinating. The process of declaring the functi ...

javascriptnode.js

Tips for accessing the 'styled' function in Material UI ReactHow to utilize the 'styled' function

Hey there, I'm facing an issue while trying to export a styled AppBar. Check out my code below: import * as React from 'react'; import { styled, useTheme } from '@mui/material/styles'; import MuiAppBar from '@mui/material/AppB ...

javascriptreactjsecmascript-6material-ui

Guide to crafting a javascript variable from MySQL through the power of PHP and AJAX

I am not very experienced in working with AJAX and javascript. I am currently trying to pass longitude and latitude values from a MySQL database to javascript, but it doesn't seem to be working as expected. Can anyone help me figure out what I might b ...

javascriptphpajax