HTML API: Stop counting noop seek operations against the max seek count.

[dmsnell]

Trac ticket: Core-62085

Weston's drafted commit message

HTML API: Stop counting no-op seek operations against the max seek count.

This allows seek() to be freely called when the current cursor at the provided bookmark.

Props dmsnell, jonsurrell, westonruter.
Fixes #62085.

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Props dmsnell, westonruter, jonsurrell.

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[sirreal]

🏓

[westonruter]

How will this impact (or not) WP_HTML_Processor::seek() since its actual bookmarks get prefixed with _?

wordpress-develop/src/wp-includes/html-api/class-wp-html-processor.php

Lines 5266 to 5275 in b071c28

	public function seek( $bookmark_name ): bool {
	// Flush any pending updates to the document before beginning.
	$this->get_updated_html();
	$actual_bookmark_name = "_{$bookmark_name}";
	$processor_started_at = $this->state->current_token
	? $this->bookmarks[ $this->state->current_token->bookmark_name ]->start
	: 0;
	$bookmark_starts_at = $this->bookmarks[ $actual_bookmark_name ]->start;
	$direction = $bookmark_starts_at > $processor_started_at ? 'forward' : 'backward';

[dmsnell]

it shouldn't because by the time it calls this parent-class method, it has supplied the underscore.

[westonruter]

OK, right. By the way, what is the reasoning behind prefixing bookmarks with underscores in HTML Processor? In WordPress/performance#1546 I'm making use of WP_HTML_Processor when available, but in the logic that injects additional markup into the head and body, it needs to obtain the start position of the bookmark. For the HTML Processor version it has to prepend the _ which seems strange, although granted this is an internal API:

• WP_HTML_Tag_Processor version
• WP_HTML_Processor version

[dmsnell]

the reason was to avoid any possible conflicts between bookmarks set by the HTML Processor itself, and the user-space code setting bookmarks. that is, any time someone calls WP_HTML_Processor::set_bookmark() it will be prefixed, but calls inside the processor to parent::set_bookmark() will be un-prefixed. it's a very basic namespacing mechanism.

[westonruter]

Committed in r59812.