I am building a library which uses the web audio api(ToneJS to be more specific).
I have tried using jsdom, mocha-jsdom with no success.
I get this error -
node_modules/tone/build/Tone.js:3869
this.input = this.output = this._gainNode = this.context.createGain();
Which makes sense and tells me that i need to use an environment with a context.
I'm not even sure how i should setup the tests for my project.
How should i setup a test environment correctly for my project?
I would suggest to not use Tone.js at all in your unit tests. Tone.js only works in the browser as it requires the Web Audio API. Instead you could use a spy/mock/stub of Tone.js which just makes sure that you use Tone as intended.
If you for example want to write a test for the AudioManager you could create a stripped down mock of Tone.js which just provides what you need.
const FakeTone = {
Players: function () { },
context: { resume () { } }
};
Next I would recommend to rewrite the AudioManager in a way that it accepts Tone as a constructor argument instead of importing it. This will make testing a lot easier. Instead of ...
import Tone from 'tone';
export class AudioManager {
// ...
generatePlayers () {
return new Tone.Players()
}
// ...
}
... it would then be ...
export class AudioManager {
constructor (Tone) {
this.Tone = Tone;
}
// ...
generatePlayers () {
return new this.Tone.Players();
}
// ...
}
... which looks a bit ugly at first, but you hopefully get used to it after a while. :-)
This will allow you to test the AudioManager with the FakeTone object.
const audioManager = new AudioManager(FakeTone);
expect(audioManager.generatePlayers()).to.be.an.instanceOf(FakeTone.Players);
You could also use something like Sinon.JS to write more advanced tests.
Related
I have a NodeJS/TypeScript app that uses Selenium WebDriver, which has approximately this snippet:
import { WebDriver } from "selenium-webdriver";
export class MyClass {
public async getTimeOrigin(driver: WebDriver): Promise<number> {
return await driver.executeScript(function () {
// This should be the DOM's timeOrigin (same as if a person types "performance.timeOrigin"
// into the Chrome DevTools console)
return performance.timeOrigin;
});
}
}
When I attempt to build the above, I get the following error message:
error TS2339: Property 'timeOrigin' does not exist on type 'Performance'
But it does certainly exist, since I can looks up the references on the Performance object and see timeOrigin inside. Can anyone please advise on how to fix this and correctly access the timeOrigin property?
performance is a global variable which is only available to the web browser you test. While you're working in NodeJS environment, it doesn't have any global performance, that's why Typescript cannot detect it and throw the error when compiling.
To fix this, you only need a simple global variable declaration:
declare var performance: any;
If you're using a lot of web interfaces in your Node environment, I recommend you import the lib lib.dom to typescript to avoid these types of errors:
{
"compilerOptions": {
"lib": [
"dom"
]
}
}
As mentioned by mcernak, another way is to use string as input to executeScript function.
To avoid the compilation issues, you can provide the script that you want to execute in context of the browser as a string(instead of a function):
public async getTimeOrigin(driver: WebDriver): Promise<number> {
return await driver.executeScript("return performance.timeOrigin;");
}
From the documentation of WebDriver.executeScript:
Executes a snippet of JavaScript in the context of the currently
selected frame or window. The script fragment will be executed as the
body of an anonymous function. If the script is provided as a function
object, that function will be converted to a string for injection into
the target window.
Maybe you can try to cast it as Performance.
import { WebDriver } from "selenium-webdriver";
export class MyClass {
public async getTimeOrigin(driver: WebDriver): Promise<number> {
return await driver.executeScript(function () {
// This should be the DOM's timeOrigin (same as if a person types "performance.timeOrigin"
// into the Chrome DevTools console)
const perf = <Performance>performance; // or "performance as Performance"
return perf.timeOrigin;
});
}
}
I am trying to enable fullscreen in my game written in Phaser 3.
I am doing it from Scene class via
this.game.scale.startFullScreen();
but getting error in f12 browser console
Uncaught TypeError: this.game.scale.startFullScreen is not a function
at TitleScene.<anonymous> (TitleScene.js:23)
at InputPlugin.emit (phaser.js:2025)
at InputPlugin.processDownEvents (phaser.js:167273)
...
In docs ScaleManager class has startFullScreen method.
Why console tells me it doesn't?
This is the full code of TitleScene.js:
export class TitleScene extends Phaser.Scene {
constructor ()
{
const config =
{
key: 'TitleScene'
}
super(config);
}
preload ()
{
this.load.image('Title', 'assets/Title.png');
}
create ()
{
this.background = this.add.image(960, 540, 'Title');
this.input.manager.enabled = true;
this.input.once('pointerdown', function () {
this.scene.start('MainScene');
this.game.scale.startFullScreen(); // here is the error
}, this);
}
}
There are two problems prevented me from resolving this problem:
I followed examples from here
https://www.phaser.io/examples/v2
But I am using the third version Phaser. And everyone who uses the same must follow examples from here
https://www.phaser.io/examples/v3
You must pay attention to url while using their site with examples. Both pages are the same from the first look. But urls are different. Also there are warning after each example using the second (old) version of engine.
And finally this function name is not startFullScreen but startFullscreen :)
I'm fairly new to typescript but I think this issue is actually indirectly related to Node. Anyway, I'm trying to write a small node lib and I'm using Typescript.
I have a class, let's say:
//foo.ts
export class Foo {
constructor(options:Options = {}) { ... }
}
However using this class directly most times will not be desirable given the nature of my lib, so I'm also exporting a module
//module.ts
import { Foo } from './foo'
let instance
... // other methods
export function init(options: Options) {
instance = new Foo(options)
}
Everything works as I expect. The issue I have is to write unit tests for module.ts. I need to write several test cases, but once I call module.init(options) once, the instance will be created and as node cache modules, importing it again in my test file will still have the foo instance there. In vanilla javascript I used the proxyquire to generate other instances of the module, but it seems that it doesn't work so well with typescript... How would I "force" node to "re-import" a "clean" instance of my module?
How would I "force" node to "re-import" a "clean" instance of my module?
A simple factory method e.g. Change
//foo.ts
export class Foo {
constructor(options:Options = {}) { ... }
}
To:
//foo.ts
class Foo {
constructor(options:Options = {}) { ... }
}
export const create(options: Options): Foo {
return new Foo(options);
}
My component has the following computed code:
textButton() {
const key = this.$root.feature.name === //...
// ...
},
Right now I'm trying desperately to mock "root" in my test, but I just don't know how. Any tips?
Vue test utils provides you with the ability to inject mocks when you mount (or shallow mount) your component.
const $root = 'some test value or jasmine spy'
let wrapper = shallow(ComponentToTest, {
mocks: { $root }
})
That should then be easily testable. Hope that helps
There are two ways to accomplish this with vue-test-utils.
One way, as mentioned above, is using the mocks mounting option.
const wrapper = shallowMount(Foo, {
mocks: {
$root: {
feature: {
name: "Some Val"
}
}
}
})
But in your case, you probably want to use the computed mouting option, which is a bit cleaner than a deep object in mocks.
const wrapper = shallowMount(Foo, {
computed: {
textButton: () => "Some Value"
}
})
Hopefully this helps!
If you are interested I am compiling a collection of simple guides on how to test Vue components here. It's under development, but feel free to ask make an issue if you need help with other related things to testing Vue components.
Solution from https://github.com/vuejs/vue-test-utils/issues/481#issuecomment-423716430:
You can set $root on the vm directly:
wrapper.vm.$root = { loading: true }
wrapper.vm.$forceUpdate()
Or you can pass in a parent component with the parentComponent mounting option. In VTU, the paren will be the $root:
const Parent = {
data() {
return {
loading: "asdas"
}
}
}
const wrapper = shallowMount(TestComponent, {
parentComponent: Parent
})
You may use a Vue Plugin inside the test to inject the mock data into localVue so that your components can access it.
import {createLocalVue, shallow} from '#vue/test-utils';
const localVue = createLocalVue();
localVue.use((Vue) => {
Vue.prototype.feature = {
name: 'Fake news!'
};
});
let wrapper = shallow(Component, {
localVue
});
I had the same issues a while ago and I came to the conclusion that accessing this.$root may be a sign that you have to further improve the way you communicate with components. Consider using the plugin structure to define globally available properties and methods not only inside the test for example. Mixins might be helpful as well.
https://v2.vuejs.org/v2/guide/plugins.html
https://v2.vuejs.org/v2/api/#mixins
I've been following the pattern for setting up TypeScript, RequireJS, and Jasmine that Steve Fenton describes here:
https://www.stevefenton.co.uk/Content/Blog/Date/201407/Blog/Combining-TypeScript-Jasmine-And-AMD-With-RequireJS/
That pattern as really worked well and truly unblocked me (yay!), but I'm now at the point where I need to customize some settings for RequireJS but I can't seem to figure out where to put my require.config call. Everywhere I've tried has caused breaks and regressions. Here are the two approaches that seem most logical/promising
In SpecRunner.cshtml
<script data-main="/Scripts/TypeScript/RequireJsConfig" src="/Scripts/require.js"></script>
In RequireJsConfig.ts
require.config({
baseUrl: "../Scripts",
paths: {
jquery: "../jquery-2.1.3"
}
});
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
// Attempt 1: When I try it this way I immediately get this error
//
// JavaScript runtime error: Object doesn't support property or method 'config'
//
import TestLoader = require("Tests/TestLoader");
TestLoader.Run();
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
// Attempt 2: When I try it this way, everything builds and runs without errors, but
// Jasmine doesn't find any of the tests. All I get is "No specs found" even
// though I see the breakpoints on my "it" statements getting hit.
//
require(["Tests/TestLoader"], (testLoader) => {
testLoader.Run();
});
// =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
jasmine.getEnv().execute();
In TestLoader.ts
import GuidHelperTests = require("Tests/T3/Helpers/GuidHelperTests");
import ObjectHelperTests = require("Tests/T3/Helpers/ObjectHelperTests");
class TestLoader {
public static Run: () => void = () => {
GuidHelperTests.Run();
ObjectHelperTests.Run();
}
}
export var Run = () => TestLoader.Run();
In GuidHelperTests.ts
import T3 = require("T3/T3Lib");
export var Run = () => {
describe("GuidHelper tests", () => {
it("GUID validator validates good GUID", () => {
// etc. ...
My guess is that Attempt 2 doesn't work because of some kind of sequencing issue where the test discovery process is happening before modules are loaded, or something like that. I'm just not versed enough in RequireJS to know what my options are here.
I prefer to keep my configuration away from my application - you can pre-register the configuration like this, and it will be picked up by RequireJS when it loads. No need to add it to your first file.
<script>
var require = {
baseUrl: "../Scripts",
paths: {
jquery: "../jquery-2.1.3"
}
};
</script>
<script data-main="/Scripts/TypeScript/RequireJsConfig" src="/Scripts/require.js"></script>