/**
  * Verify basic functionality of clear().
  *
  * @test
  * @covers ::clear
  *
  * @return void
  */
 public function clear()
 {
     $cache = new ArrayCache();
     $request = new Request('not under test', 'not under test', [], []);
     $cache->set($request, new Response(200, [], []));
     $this->assertNotNull($cache->get($request));
     $cache->clear();
     $this->assertNull($cache->get($request));
 }