Code Coverage for /src/src/Utils/Timing.php

1	<?php
2	declare( strict_types = 1 );
3
4	namespace Wikimedia\Parsoid\Utils;
5
6	use Wikimedia\Assert\Assert;
7
8	/**
9	* A helper class to make it easier to compute timing metrics.
10	*/
11	class Timing {
12	/**
13	* This is typically a StatsdDataFactoryInterface, but really could be
14	* anything which has a `timing()` method. Set it to `null` to disable
15	* metrics.
16	*
17	* @var ?object
18	*/
19	private $metrics;
20	/* @var float */
21	private $startTime;
22
23	private function __construct( ?object $metrics ) {
24	$this->metrics = $metrics;
25	$this->startTime = self::millis();
26	}
27
28	/**
29	* Return the current number of milliseconds since the epoch, as a float.
30	*/
31	public static function millis(): float {
32	return 1000 * microtime( true );
33	}
34
35	/**
36	* End this timing measurement, reporting it under the given `name`.
37	* @param ?string $name
38	* @return float Number of milliseconds reported
39	*/
40	public function end( ?string $name = null ): float {
41	$elapsed = self::millis() - $this->startTime;
42	if ( $this->metrics ) {
43	Assert::invariant( $name !== null, 'Recording metric without a key.' );
44	$this->metrics->timing( $name, $elapsed );
45	}
46	return $elapsed;
47	}
48
49	/**
50	* Start a timing measurement, logging it to the given `$metrics` object
51	* (which just needs to have a `timing()` method).
52	* @param ?object $metrics
53	* @return Timing
54	*/
55	public static function start( ?object $metrics = null ): Timing {
56	return new Timing( $metrics );
57	}
58	}