throw new exception laravel doesnt work in expectException PHP unit - php

Question

The exception is thrown correctly in the program, but the test does not detect it. Why??
public function null_user_send()
{
$message = 'Hi';
$response = $this->post(route('dialogSend'), ['to' => -1, 'message' => $message]);
$this->assertDatabaseMissing('messages', ['to' => -1, 'message' => $message]);
$this->expectException(Exception::class);
$response->assertStatus(500);
}
MailController:
/** #throws \Exception */
public function dialogSend(Request $request)
{
$handler = app(MailHandler::class);
if ($request->input('to') <= 0) {
throw new \Exception('Параметр "to" имел отрицательное значение', 500);
}
...
}
Test response: 'Failed asserting that exception of type "Exception" is thrown.'
And it doesn't matter what class of exceptions, nothing works. Pls help

Answer 1

Check the namespace of the exception you are testing
$this->expectException(Exception::class);
probably should be
$this->expectException(\Exception::class);
This is because your test itself sits in its own namespace (depend on the type of test). What your test is may actually be seeing is
$this->expectException(\Tests\Exception::class);
which will of course never be thrown since it doesn't exist.
One of the reasons you are having trouble diagnosing this is the nature of your tests. There are a few things there, while not strictly wrong, are going to make your testing that much harder to determine the cause of your problem.
You're trying to test too much at once. Separate each concern into its own test so that you can first determine if the database is empty, then if it throws an exception, then if it returns a 500 error. You are essentially testing three different aspects of your application here.
public function null_user_send()
{
// Arrange
$message = 'Hi';
// Act
$response = $this->post(route('dialogSend'), ['to' => -1, 'message' => $message]);
// Assert
$this->assertDatabaseMissing('messages', ['to' => -1, 'message' => $message]);
}
public function does_an_exception()
{
// Arrange, Act
...
// Assert
$this->expectException(Exception::class);
}
public function returns_server_erro()
{
// Arrange, Act
...
// Assert
$response->assertStatus(500);
}
Give your tests meaning in their names. This will help you immensely in the future when you can't remember what something is meant to do verus what it is actually doing.
public function it_should_not_have_a_message_if_the_input_is_wrong()
{
// database test
}
public function it_should_throw_an_exception_if_the_input_is_wrong()
{
// exception test
}
public function it_should_return_a_500_error_if_the_input_is_wrong()
{
// http code test
}
A good test should be able to answer the following question:
If I set up my application like this, and then I do that, then my application should now look like this.
This is where the Arrange (organise my application), Act (do something) and Assert (check my application) comes from in the code above.
There are couple of other things you might to look at, although this will be up you depending on your needs.
You look like you're doing validation on input here. You should probably throw a 400 or 422 error if your input is wrong
The 500 error code on your exception probably won't really do anything, it won't be related to the 500 HTTP status code, unless you have something in your error handling that does that.