function TimerTest::testTimer

Tests Timer::read() time accumulation accuracy across multiple restarts.

@covers ::start
@covers ::stop
@covers ::read

File

core/tests/Drupal/Tests/Component/Utility/TimerTest.php, line 24

Class

TimerTest

Tests the Timer system.

Namespace

Code

public function testTimer() {
  Timer::start('test');
  usleep(5000);
  $value = Timer::read('test');
  usleep(5000);
  $value2 = Timer::read('test');
  usleep(5000);
  $value3 = Timer::read('test');
  usleep(5000);
  $value4 = Timer::read('test');
  // Although we sleep for 5 milliseconds, we should test that at least 4 ms
  // have past because usleep() is not reliable on Windows. See
  // http://php.net/manual/function.usleep.php for more information. The
  // purpose of the test to validate that the Timer class can measure elapsed
  // time not the granularity of usleep() on a particular OS.
  $this->assertGreaterThanOrEqual(4, $value, 'Timer failed to measure at least 4 milliseconds of sleeping while running.');
  $this->assertGreaterThanOrEqual($value + 4, $value2, 'Timer failed to measure at least 8 milliseconds of sleeping while running.');
  $this->assertGreaterThanOrEqual($value2 + 4, $value3, 'Timer failed to measure at least 12 milliseconds of sleeping while running.');
  $this->assertGreaterThanOrEqual($value3 + 4, $value4, 'Timer failed to measure at least 16 milliseconds of sleeping while running.');
  // Stop the timer.
  $value5 = Timer::stop('test');
  $this->assertGreaterThanOrEqual($value4, $value5['time'], 'Timer measured after stopping was not greater than last measurement.');
  // Read again.
  $value6 = Timer::read('test');
  $this->assertEquals($value5['time'], $value6, 'Timer measured after stopping was not equal to the stopped time.');
  // Restart.
  Timer::start('test');
  usleep(5000);
  $value7 = Timer::read('test');
  $this->assertGreaterThanOrEqual($value6 + 4, $value7, 'Timer failed to measure at least 16 milliseconds of sleeping while running.');
  // Stop again.
  $value8 = Timer::stop('test');
  $value9 = Timer::read('test');
  $this->assertEquals($value8['time'], $value9, 'Timer measured after stopping not equal to stop time.');
}