JavaScript Unit Test & Code Coverage

Premnath Thimma

Thought

A solution is only as good as your understanding of the problem.

Thought

Why Unit Test?

• Promote better design – loose coupling

• Helps developers to write

– Testable unit

– Maintainable code

• Improves quality at unit level

Difficulties/Problems

• Lack of structure

• Function not exposed outside

• Complexity in the function ( > 10 lines )

• Tight coupling between components

Solutions from AngularJS

• Structure– Module, Model, View, Controller, Service,

Templates, Filters

• Function not exposed outside– Service, Factory, Constant, Value

• Complexity in the function ( > 10 lines )– Module, Injectable Components

• Tight coupling between components– Loose coupling with Structure, Module

Tools

• JS Libraries

– Jasmine, Qunit, Mocha

• Test Runner

– Chutzpah

• Visual Studio Plug-ins

– Chutzpah Test Adapter for the Test Explorer

– Chutzpah Test Runner Context Menu Extension

– Karma Test Adapter

Get to know Jasmine

• Supports BDD (User Story)

– Spec (describe, it)

– Nest-able Spec

• Powerful Matchers (+ Customer Matcher)

• Powerful concept like Spy

• Supported by Visual Studio

– Test Explorer (includes JS Unit Tests)

– Recognizes your changes to Unit Test

Get to know Chutzpah

• Test Runner– Right Click and Run

– Runs automatically in Visual Studio when you make changes to Unit Test

• Code Coverage– From Visual Studio

– From Command Line

– Exclude and Include files using expression

– Context sensitive to File or Folder

Demo

Questions

References

• https://github.com/mmanela/chutzpah

• http://chutzpah.codeplex.com/documentation

• http://jasmine.github.io/edge/introduction.html

• https://docs.angularjs.org/guide/unit-testing