WP_Text_Diff_Renderer_Table::interleave_changed_lines() public WP 2.6.0

Takes changed blocks and matches which rows in orig turned into which rows in final.

{} It's a method of the class: WP_Text_Diff_Renderer_Table{}

No Hooks.

Return

Array. Array containing results of comparing the original text to the final text.

Usage

$WP_Text_Diff_Renderer_Table = new WP_Text_Diff_Renderer_Table();
$WP_Text_Diff_Renderer_Table->interleave_changed_lines( $orig, $final );

$orig(array) (required)

Lines of the original version of the text.

$final(array) (required)

Lines of the final version of the text.

Changelog

Code of WP_Text_Diff_Renderer_Table::interleave_changed_lines() WP Text Diff Renderer Table::interleave changed lines ^{WP 5.7.2}

<?php
public function interleave_changed_lines( $orig, $final ) {

	// Contains all pairwise string comparisons. Keys are such that this need only be a one dimensional array.
	$matches = array();
	foreach ( array_keys( $orig ) as $o ) {
		foreach ( array_keys( $final ) as $f ) {
			$matches[ "$o,$f" ] = $this->compute_string_distance( $orig[ $o ], $final[ $f ] );
		}
	}
	asort( $matches ); // Order by string distance.

	$orig_matches  = array();
	$final_matches = array();

	foreach ( $matches as $keys => $difference ) {
		list($o, $f) = explode( ',', $keys );
		$o           = (int) $o;
		$f           = (int) $f;

		// Already have better matches for these guys.
		if ( isset( $orig_matches[ $o ] ) && isset( $final_matches[ $f ] ) ) {
			continue;
		}

		// First match for these guys. Must be best match.
		if ( ! isset( $orig_matches[ $o ] ) && ! isset( $final_matches[ $f ] ) ) {
			$orig_matches[ $o ]  = $f;
			$final_matches[ $f ] = $o;
			continue;
		}

		// Best match of this final is already taken? Must mean this final is a new row.
		if ( isset( $orig_matches[ $o ] ) ) {
			$final_matches[ $f ] = 'x';
		} elseif ( isset( $final_matches[ $f ] ) ) {
			// Best match of this orig is already taken? Must mean this orig is a deleted row.
			$orig_matches[ $o ] = 'x';
		}
	}

	// We read the text in this order.
	ksort( $orig_matches );
	ksort( $final_matches );

	// Stores rows and blanks for each column.
	$orig_rows      = array_keys( $orig_matches );
	$orig_rows_copy = $orig_rows;
	$final_rows     = array_keys( $final_matches );

	// Interleaves rows with blanks to keep matches aligned.
	// We may end up with some extraneous blank rows, but we'll just ignore them later.
	foreach ( $orig_rows_copy as $orig_row ) {
		$final_pos = array_search( $orig_matches[ $orig_row ], $final_rows, true );
		$orig_pos  = (int) array_search( $orig_row, $orig_rows, true );

		if ( false === $final_pos ) { // This orig is paired with a blank final.
			array_splice( $final_rows, $orig_pos, 0, -1 );
		} elseif ( $final_pos < $orig_pos ) { // This orig's match is up a ways. Pad final with blank rows.
			$diff_array = range( -1, $final_pos - $orig_pos );
			array_splice( $final_rows, $orig_pos, 0, $diff_array );
		} elseif ( $final_pos > $orig_pos ) { // This orig's match is down a ways. Pad orig with blank rows.
			$diff_array = range( -1, $orig_pos - $final_pos );
			array_splice( $orig_rows, $orig_pos, 0, $diff_array );
		}
	}

	// Pad the ends with blank rows if the columns aren't the same length.
	$diff_count = count( $orig_rows ) - count( $final_rows );
	if ( $diff_count < 0 ) {
		while ( $diff_count < 0 ) {
			array_push( $orig_rows, $diff_count++ );
		}
	} elseif ( $diff_count > 0 ) {
		$diff_count = -1 * $diff_count;
		while ( $diff_count < 0 ) {
			array_push( $final_rows, $diff_count++ );
		}
	}

	return array( $orig_matches, $final_matches, $orig_rows, $final_rows );
}