Original subtitles

In the last few meters we have learned about the basics of unit testing in flutter and we are now ready

to test a class that is a little bit more complex than the non empty string validator and in the process

of doing this we will learn a bit more about the flutter testing API.

So as a next step we can open the four month class that we use to format our words dates and currency

values in the up.

And then we can add a new Dart file called for format on the score fast inside the test packets.

And like we have done before we can import faster test and we can also add a void Main method like this

and to make our life easier.

We can split up what Ed into and keep the did testify on the left and the file that we want to test

on the right.

And as we can see here we have four different methods and we could write multiple tests for each of

them.

So it would be nice if somehow we could group the tests that belong together.

And it turns out that we can do that by using a test group so we can type being group like this without

description.

And here we could type being ours and then we need to pass a closure like this.

And inside the body of this closure we cannot.

All the tests for this method.

So let's start with the first one.

And here I can type test a description of positive and then inside the test body.

I'm going to write expect that for month and I need to import this second draft format that house with

a parameter of 10 for example is equal to 10 H which is the string representation that I want and if

I want I can already run this test and as I can see.

Now this is green.

So we can continue.

Next I want to add more tests and I'm particularly interested in what happens when we pass zero.

When we pass on negative value and when we pass a decimal number so let's up this test quickly and I

can copy and paste this method in here I can rename the description to zero and I can pass for month

of ours with zero and I expect zero H and then I can do the same thing for the negative case.

And here I could pass for example hours of minus five and I'm still going to expect to see zero hours

because this is how this logic was implemented.

Finally I cannot the decimal case so I can copy paste this I'm going to name this decimal and I'm going

to pass a value of 4.5 an unexpected value of 4.5 H and then I can run all the tests again and I can

see that they have all passed.

OK so let's continue on the next video.