Mockery example

mockery.php

$user = [
  "username" => $post['username'],
  "password" => $post['password'],
  "name"     => $post['name'],
];

 // Simple Mock
$mock_class = SomeDamnClass::class;
$mock = Mockery::mock($nero_class);
$mock->shouldReceive('getUserByUsername')
     ->times(1)
     ->with($user)
     ->andReturn(false);

// Chained Method mock
$mock->shouldReceive('getErrorMessage->getMessage')
     ->times(1)
     ->withAnyArgs()
     ->andReturn('
      {
        "errors": [
          "The username has already been taken"
        ]
      }
     ');