I have two tests in my test group. One of the tests use it and the other one uses test. Both of them seem to be working very similarly. What is the difference between them?
describe('updateAll', () => {
it('no force', () => {
return updateAll(TableName, ["fileName"], {compandId: "test"})
.then(updatedItems => {
let undefinedCount = 0;
for (let item of updatedItems) {
undefinedCount += item === undefined ? 1 : 0;
}
// console.log("result", result);
expect(undefinedCount).toBe(updatedItems.length);
})
});
test('force update', () => {
return updateAll(TableName, ["fileName"], {compandId: "test"}, true)
.then(updatedItems => {
let undefinedCount = 0;
for (let item of updatedItems) {
undefinedCount += item === undefined ? 1 : 0;
}
// console.log("result", result);
expect(undefinedCount).toBe(0);
})
});
});
It seems that test is in the official API of Jest, but it is not.
The Jest docs state it is an alias of test. So they are exactly the same from a functional point of view. They exist both to enable to make a readable English sentence from your test.
They do the same thing, but their names are different and with that their interaction with the name of the test.
test
What you write:
describe('yourModule', () => {
test('if it does this thing', () => {});
test('if it does the other thing', () => {});
});
What you get if something fails:
yourModule > if it does this thing
it
What you write:
describe('yourModule', () => {
it('should do this thing', () => {});
it('should do the other thing', () => {});
});
What you get if something fails:
yourModule > should do this thing
So it's about readability not about functionality.
In my opinion, it really has a point when it comes to read the result of a failing test that you haven't written yourself. It helps to faster understand what the test is about.
Some developer also shorten the Should do this thing to Does this thing which is a bit shorter and also fits semantically to the it notation.
As the other answers have clarified, they do the same thing.
I believe the two are offered to allow for either 1) "RSpec" style tests like:
const myBeverage = {
delicious: true,
sour: false,
};
describe('my beverage', () => {
it('is delicious', () => {
expect(myBeverage.delicious).toBeTruthy();
});
it('is not sour', () => {
expect(myBeverage.sour).toBeFalsy();
});
});
or 2) "xUnit" style tests like:
function sum(a, b) {
return a + b;
}
test('sum adds 1 + 2 to equal 3', () => {
expect(sum(1, 2)).toBe(3);
});
Documentation: