PHPUnit: Mocking Interface

PHPUnitMockInterface.md

use PHPUnit\Framework\TestCase;

interface Greeting
{
    public function hello($name);
}

class GreetingTest extends TestCase
{
    public function testSayHello()
    {
        $greeting = $this->getMockForAbstractClass(Greeting::class);

        $greeting->method('hello')->will($this->returnValue('Hello Lucas'));

        $this->assertEquals('Hello Lucas', $greeting->hello('Lucas'));
    }
}