1	<?php
2
3	declare(strict_types=1);
4
5	namespace Drupal\display_builder;
6
7	use Drupal\Component\Render\FormattableMarkup;
8
9	/**
10	* History interface.
11	*
12	* When you implement Undo and Redo, you want to keep track of the history
13	* of this state at different points in time.
14	*
15	* Inspired from https://redux.js.org/usage/implementing-undo-history
16	*/
17	interface HistoryInterface {
18
19	/**
20	* Get current step.
21	*
22	* @return \Drupal\display_builder\HistoryStep|null
23	*   The current data.
24	*/
25	public function getCurrent(): ?HistoryStep;
26
27	/**
28	* Get the state of the current step.
29	*
30	* @return array
31	*   The current state.
32	*/
33	public function getCurrentState(): array;
34
35	/**
36	* Set a new present.
37	*
38	* @param array $state
39	*   The state to set.
40	* @param string|\Drupal\Component\Render\FormattableMarkup $log_message
41	*   (Optional) The log message.
42	* @param bool $check_hash
43	*   (Optional) Should check hash to avoid duplicates. Default to TRUE.
44	*/
45	public function setNewPresent(array $state, FormattableMarkup|string $log_message = '', bool $check_hash = TRUE): void;
46
47	/**
48	* Get number of past logs.
49	*
50	* @return int
51	*   The number of past logs.
52	*/
53	public function getCountPast(): int;
54
55	/**
56	* Get number of future logs.
57	*
58	* @return int
59	*   The number of future logs.
60	*/
61	public function getCountFuture(): int;
62
63	/**
64	* Move history to the last past state.
65	*/
66	public function undo(): void;
67
68	/**
69	* Move history to the first future state.
70	*/
71	public function redo(): void;
72
73	/**
74	* Reset history to the current state.
75	*/
76	public function clear(): void;
77
78	}

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Paths

Below are the source code lines that represent each code path as identified by Xdebug. Please note a path is not necessarily coterminous with a line, a line may contain multiple paths and therefore show up more than once. Please also be aware that some paths may include implicit rather than explicit branches, e.g. an if statement always has an else as part of its logical flow even if you didn't write one.