Specs for Calculator. Jasmine, JS5

posted in My Instructions for beginners

Published February 23, 2019

Javascript Learning

Specifications:

"Add(a, b)" method must to sum positive numbers. Specification name: Add_SumPositiveNumbers_ReturnsSum
"Sub(a, b)" method must to subtract positive numbers. Specification name: Sub_SubtractPositiveNumbers_ReturnsSub

Source Code: https://github.com/8Observer8/calculator-jasmine-es5

Instruction:

Create the "calculator-jasmine-es5" folder
Search in the Internet: cdn jasmine
Create the "SpecRunner.html file in the "calculator-jasmine-es5" folder and add links on files:


<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Jasmine Spec Runner v3.3.0</title>
    <link rel="shortcut icon" type="image/png"
        href="https://cdnjs.cloudflare.com/ajax/libs/jasmine/2.0.0/jasmine_favicon.png">
    <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/jasmine/3.3.0/jasmine.min.css">

    <script src="https://cdnjs.cloudflare.com/ajax/libs/jasmine/3.3.0/jasmine.min.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/jasmine/3.3.0/jasmine-html.min.js"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/jasmine/3.3.0/boot.min.js"></script>

    <!-- include source files here... -->
    <script src="src_client/calculator.js"></script>

    <!-- include spec files here... -->
    <script src="src_specs/calculator_tests.js"></script>
</head>

</html>

Note. Files "calculator_tests.js" was not created yet but we added links on them above.

Create the "src_client" folder. Create the "calculator.js" file the the "src_client" folder
Create the "src_specs" folder. Create the "calculator_tests.js" file the the "src_specs" folder
Add our specs described above to the "calculator_tests.js" file:

calculator_tests.js


describe("Calculator", function()
{
    it("Add_SumPositiveNumbers_ReturnsSum", function()
    {
        // Arrange
        var calculator = new Calculator();
        var a = 5;
        var b = 2;
        var expectedSum = 7;

        // Act
        var actualSum = calculator.Add(a, b);

        // Assert
        expect(actualSum).toEqual(expectedSum);
    });

    it("Sub_SubtractPositiveNumbers_ReturnsSub", function()
    {
        // Arrange
        var calculator = new Calculator();
        var a = 5;
        var b = 2;
        var expectedSub = 3;

        // Act
        var actualSub = calculator.Sub(a, b);

        // Assert
        expect(actualSub).toEqual(expectedSub);
    });
});

Open the "SpecRunner.html" in a browser to run tests. You will see errors in the browser because we did not implement the methods: Add(a, b) and Sub(a, b)
Let's implement these methods and open the "SpecRunner.html" in the browser again to run tests. You will see that the tests are passed.

calculator.js


var Calculator = function()
{

};

Calculator.prototype.Add = function(a, b)
{
    return a + b;
};

Calculator.prototype.Sub = function(a, b)
{
    return a - b;
};