'How to check if a value is an integer or a string in jasmine.js?

I am writing unit test using Jasmine in a web app using BackboneJS.
There are a lot of examples showing you how to check a value in this way:

        it("should set the id property to default value", function()
        {
            expect(this.task.get("id")).toEqual(null);
        });

But I can't find any example checking if an attribute whether is number or string in Javascript using Jasmine.

Is it appropriate to make a check like this?
If yes, what is the proper way to make it?

Example: I want to check if the id is an integer > 0. How can I make it in Jasmine?

jasmine


Solution 1:[1]

I would make something like this:

    describe("when instantiated", function() 
    {
        it("should exhibit attributes", function () 
        {  
            .....
            expect(this.task.get("id")).toMatch(/\d{1,}/);
            .....
        });
    });

Solution 2:[2]

For posterity, one of the questions posed here is to test whether a value is a number. From the jasmine docs:

expect(12).toEqual(jasmine.any(Number));

Solution 3:[3]

Honestly, I don't know what the proper way is, but I will write something like that: 

 it("should set the id property to default value", function () {
        var id = this.task.get("id");
        expect(typeof id).toEqual('number');
        expect(id).toBeGreaterThan(0);
 });

Solution 4:[4]

expect( this.task.get("id") ).toBeGreaterThan( 0 );

If we have in consideration that:

expect( 1 ).toBeGreaterThan( 0 );   // => true
expect( "1" ).toBeGreaterThan( 0 ); // => true
expect( "a" ).toBeGreaterThan( 0 ); // => false

Solution 5:[5]

You can try:

it('should be integer', function()
{
    var id = this.task.get("id");

    expect(id).toEqual(jasmine.any(Number));
    expect(id).toBeGreaterThan(0);
    expect(Math.trunc(id)).toEqual(id);
});

If you have a number that is not an integer, truncating it should lead to a number that is different, which will cause the appropriate test failure.

If you do not have support for ES6, you can use floor instead.

Solution 6:[6]

I've used underscorejs to check this kind of things:

it('should be a number', function() {
  expect(_.isNumber(this.task.get('id'))).toBeTruthy();
});

Solution 7:[7]

This will make sure that a result is a number.

it("expect the result to be a number", () => {
    expect(5).not.toBeNaN;
});

While this will make sure the result not to be a number

it("expect the result not to be a number", () => {
    expect('five').toBeNaN;
});

This makes sure that the number is greater than or equal to zero

it("expect the result to be >=0", () => {
    expect(5).toBeGreaterThanOrEqual(0)
});

Solution 8:[8]

expect(id).toBeInstanceOf(Number)
expect(id).toBeGreaterThan(0);

https://jasmine.github.io/api/edge/matchers.html#toBeInstanceOf

Sources

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Source: Stack Overflow

Solution Source
Solution 1 antonjs
Solution 2 Diogo Cardoso
Solution 3 theotheo
Solution 4 fguillen
Solution 5
Solution 6 Michael Radionov
Solution 7 Peter Csala
Solution 8 jobwat

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