wp-includes/class-wp-block-parser.php:236Scans the document from where we last left off and finds the next valid token to parse if it exists
array public function next_token() { $matches = null; /* * aye the magic * we're using a single RegExp to tokenize the block comment delimiters * we're also using a trick here because the only difference between a * block opener and a block closer is the leading `/` before `wp:` (and * a closer has no attributes). we can trap them both and process the * match back in PHP to see which one it was. */ $has_match = preg_match( '/<!--\s+(?P<closer>\/)?wp:(?P<namespace>[a-z][a-z0-9_-]*\/)?(?P<name>[a-z][a-z0-9_-]*)\s+(?P<attrs>{(?:(?:[^}]+|}+(?=})|(?!}\s+\/?-->).)*+)?}\s+)?(?P<void>\/)?-->/s', $this->document, $matches, PREG_OFFSET_CAPTURE, $this->offset ); // if we get here we probably have catastrophic backtracking or out-of-memory in the PCRE. if ( false === $has_match ) { return array( 'no-more-tokens', null, null, null, null ); } // we have no more tokens. if ( 0 === $has_match ) { return array( 'no-more-tokens', null, null, null, null ); } list( $match, $started_at ) = $matches[0]; $length = strlen( $match ); $is_closer = isset( $matches['closer'] ) && -1 !== $matches['closer'][1]; $is_void = isset( $matches['void'] ) && -1 !== $matches['void'][1]; $namespace = $matches['namespace']; $namespace = ( isset( $namespace ) && -1 !== $namespace[1] ) ? $namespace[0] : 'core/'; $name = $namespace . $matches['name'][0]; $has_attrs = isset( $matches['attrs'] ) && -1 !== $matches['attrs'][1]; /* * Fun fact! It's not trivial in PHP to create "an empty associative array" since all arrays * are associative arrays. If we use `array()` we get a JSON `[]` */ $attrs = $has_attrs ? json_decode( $matches['attrs'][0], /* as-associative */ true ) : array(); /* * This state isn't allowed * This is an error */ if ( $is_closer && ( $is_void || $has_attrs ) ) { // we can ignore them since they don't hurt anything. } if ( $is_void ) { return array( 'void-block', $name, $attrs, $started_at, $length ); } if ( $is_closer ) { return array( 'block-closer', $name, null, $started_at, $length ); } return array( 'block-opener', $name, $attrs, $started_at, $length ); }Introduced in 5.0.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/class-wp-block-parser.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.