expect()
Open source
expect()
expect
is a wrapper of check to provide BDD style of assertions in k6. It implements the Chai Expect API:
JavaScript
import http from 'k6/http';
import { describe, expect } from 'https://jslib.k6.io/k6chaijs/4.3.4.3/index.js';
export default function () {
describe('Basic test', () => {
expect({ a: 1 }).to.not.have.property('b');
expect(2).to.equal(2);
expect({ a: 1 }).to.deep.equal({ a: 1 });
expect({ a: { b: ['x', 'y'] } }).to.have.nested.property('a.b[1]');
expect({ a: 1 }).to.have.own.property('a');
expect([1, 2]).to.have.ordered.members([1, 2]).but.not.have.ordered.members([2, 1]);
expect({ a: 1, b: 2 }).to.not.have.any.keys('c', 'd');
expect({ a: 1, b: 2 }).to.have.all.keys('a', 'b');
expect('foo').to.be.a('string');
expect([1, 2, 3]).to.be.an('array').that.includes(2);
expect('foobar').to.include('foo');
expect(1).to.equal(1);
expect(true).to.be.true;
expect(false).to.be.false;
expect(null).to.be.null;
expect(undefined).to.be.undefined;
expect(NaN).to.be.NaN;
expect(1).to.equal(1);
expect([]).to.be.empty;
expect({}).not.to.be.arguments;
expect(1).to.equal(1);
expect({ a: 1 }).to.eql({ a: 1 }).but.not.equal({ a: 1 });
expect('foo').to.have.lengthOf(3);
expect(2).to.equal(2);
expect(1).to.equal(1);
expect(2).to.be.at.most(3);
expect(2).to.equal(2);
expect({ a: 1 }).to.not.be.an.instanceof(Array);
expect({ a: 1 }).to.have.property('a');
expect([1, 2, 3]).to.have.lengthOf(3);
expect('foobar').to.match(/^foo/);
expect('foobar').to.have.string('bar');
expect({ a: 1, b: 2 }).to.have.all.keys('a', 'b');
const badFn = function () {
throw new TypeError('Illegal salmon!');
};
expect(badFn).to.throw();
expect(1).to.satisfy(function (num) {
return num > 0;
});
expect(1.5).to.equal(1.5);
expect([1, 2, 3]).to.have.members([2, 1, 3]);
expect('Today is sunny').to.contain.oneOf(['sunny', 'cloudy']);
expect({ a: 1 }).to.be.extensible;
expect(1).to.be.finite;
});
}
When you run this test with k6 run script.js
, the output at the end of the test shows:
bash
default ✓ [======================================] 1 VUs 00m00.0s/10m0s 1/1 iters, 1 per VU
█ Basic test
✓ expected ${this} to not have property 'b'
✓ expected ${this} to equal 2
✓ expected ${this} to deeply equal { a: 1 }
✓ expected ${this} to have nested property 'a.b[1]'
✓ expected ${this} to have own property 'a'
✓ expected ${this} to be an array
✓ expected ${this} to have the same ordered members as [ 1, 2 ]
✓ expected ${this} to not have the same ordered members as [ 2, 1 ]
✓ expected ${this} to not have keys 'c', or 'd'
✓ expected ${this} to have keys 'a', and 'b'
✓ expected ${this} to be a string
✓ expected ${this} to include 2
✓ expected ${this} to include 'foo'
✓ expected ${this} to equal 1
✓ expected ${this} to be true
✓ expected ${this} to be false
✓ expected ${this} to be null
✓ expected ${this} to be undefined
✓ expected ${this} to be NaN
✓ expected ${this} to be empty
✓ expected ${this} to not be arguments
✓ expected ${this} to not equal { a: 1 }
✓ expected ${this} to have property 'length'
✓ expected ${this} to have a length of 3 got ${actual}
✓ expected ${this} to be at most 3
✓ expected ${this} to not be an instance of Array
✓ expected ${this} to have property 'a'
✓ expected ${this} to match /^foo/
✓ expected ${this} to contain 'bar'
✓ expected ${this} to be a function
✓ expected ${this} to throw an error
✓ expected ${this} to satisfy [Function]
✓ expected ${this} to equal 1.5
✓ expected ${this} to have the same members as [ 2, 1, 3 ]
✓ expected ${this} to contain one of [ 'sunny', 'cloudy' ]
✓ expected ${this} to be extensible
✓ expected ${this} to be a finite number
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