Weird problem with phpunit, keeps running test on old file

I am watching the laravel 5.4 from Scratch video about phpunit. I modified the file, 'ExampleTest.php'. I even renamed the file.

When I rerun the phpunit test on the newly named changed file, it cannot find it. However, if I run the test on the old file, it finds it and passes. What's going on? Is it somehow buffering the old file? If so, is there a way to clear it and run the test on the newly named changed file? This is driving me crazy.