Cannot open file "/tests/ExampleTest.php" Laravel5 using Windows10

i am running phpunit testing in laravel5 on windows 10,and getting this error by running the following command.

Cannot open file "/tests/ExampleTest.php",
D:\wamp64\www\forum\vendor\bin>phpunit /tests/ ExampleTest.php

Can you please suggest me what could be the issue?

via Chebli Mohamed