diff -r 902822492a68 -r fe660c52c48f includes/diffengine/Engine/string.php
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/includes/diffengine/Engine/string.php	Wed Jun 13 16:07:17 2007 -0400
@@ -0,0 +1,216 @@
+<?php
+/**
+ * Parses unified or context diffs output from eg. the diff utility.
+ *
+ * Example:
+ * <code>
+ * $patch = file_get_contents('example.patch');
+ * $diff = &new Text_Diff('string', array($patch));
+ * $renderer = &new Text_Diff_Renderer_inline();
+ * echo $renderer->render($diff);
+ * </code>
+ *
+ * @author    �rjan Persson <o@42mm.org>
+ * @copyright Copyright 2005 �rjan Persson
+ * @package   Text_Diff
+ * @since     0.2.0
+ * @access    private
+ */
+class Text_Diff_Engine_string {
+
+    /**
+     * Parses a unified or context diff.
+     *
+     * First param contains the whole diff and the second can be used to force 
+     * a specific diff type. If the second parameter is 'autodetect', the 
+     * diff will be examined to find out which type of diff this is.
+     * 
+     * @param string $diff  The diff content.
+     * @param string $mode  The diff mode of the content in $diff. One of
+     *                      'context', 'unified', or 'autodetect'.
+     *
+     * @return array  List of all diff operations.
+     */
+    function diff($diff, $mode = 'autodetect')
+    {
+        if ($mode != 'autodetect' && $mode != 'context' && $mode != 'unified') {
+            die_friendly('Text_Diff', '<p>Type of diff is unsupported</p>');
+        }
+
+        if ($mode == 'autodetect') {
+            $context = strpos($diff, '***');
+            $unified = strpos($diff, '---');
+            if ($context === $unified) {
+                die_friendly('Text_Diff', '<p>Type of diff could not be detected</p>');
+            } elseif ($context === false || $context === false) {
+                $mode = $context !== false ? 'context' : 'unified';
+            } else {
+                $mode = $context < $unified ? 'context' : 'unified';
+            }
+        }
+
+        // split by new line and remove the diff header
+        $diff = explode("\n", $diff);
+        array_shift($diff);
+        array_shift($diff);
+
+        if ($mode == 'context') {
+            return $this->parseContextDiff($diff);
+        } else {
+            return $this->parseUnifiedDiff($diff);
+        }
+    }
+
+    /**
+     * Parses an array containing the unified diff.
+     *
+     * @param array $diff  Array of lines.
+     *
+     * @return array  List of all diff operations.
+     */
+    function parseUnifiedDiff($diff)
+    {
+        $edits = array();
+        $end = count($diff) - 1;
+        for ($i = 0; $i < $end;) {
+            $diff1 = array();
+            switch (substr($diff[$i], 0, 1)) {
+            case ' ':
+                do {
+                    $diff1[] = substr($diff[$i], 1);
+                } while (++$i < $end && substr($diff[$i], 0, 1) == ' ');
+                $edits[] = &new Text_Diff_Op_copy($diff1);
+                break;
+            case '+':
+                // get all new lines
+                do {
+                    $diff1[] = substr($diff[$i], 1);
+                } while (++$i < $end && substr($diff[$i], 0, 1) == '+');
+                $edits[] = &new Text_Diff_Op_add($diff1);
+                break;
+            case '-':
+                // get changed or removed lines
+                $diff2 = array();
+                do {
+                    $diff1[] = substr($diff[$i], 1);
+                } while (++$i < $end && substr($diff[$i], 0, 1) == '-');
+                while ($i < $end && substr($diff[$i], 0, 1) == '+') {
+                    $diff2[] = substr($diff[$i++], 1);
+                }
+                if (count($diff2) == 0) {
+                    $edits[] = &new Text_Diff_Op_delete($diff1);
+                } else {
+                    $edits[] = &new Text_Diff_Op_change($diff1, $diff2);
+                }
+                break;
+            default:
+                $i++;
+                break;
+            }
+        }
+        return $edits;
+    }
+
+    /**
+     * Parses an array containing the context diff.
+     *
+     * @param array $diff  Array of lines.
+     *
+     * @return array  List of all diff operations.
+     */
+    function parseContextDiff(&$diff)
+    {
+        $edits = array();
+        $i = $max_i = $j = $max_j = 0;
+        $end = count($diff) - 1;
+        while ($i < $end && $j < $end) {
+            while ($i >= $max_i && $j >= $max_j) {
+                // find the boundaries of the diff output of the two files
+                for ($i = $j;
+                     $i < $end && substr($diff[$i], 0, 3) == '***';
+                     $i++);
+                for ($max_i = $i;
+                     $max_i < $end && substr($diff[$max_i], 0, 3) != '---';
+                     $max_i++);
+                for ($j = $max_i;
+                     $j < $end && substr($diff[$j], 0, 3) == '---';
+                     $j++);
+                for ($max_j = $j;
+                     $max_j < $end && substr($diff[$max_j], 0, 3) != '***';
+                     $max_j++);
+            }
+
+            // find what hasn't been changed
+            $array = array();
+            while ($i < $max_i &&
+                   $j < $max_j &&
+                   strcmp($diff[$i], $diff[$j]) == 0) {
+                $array[] = substr($diff[$i], 2);
+                $i++;
+                $j++;
+            }
+            while ($i < $max_i && ($max_j-$j) <= 1) {
+                if ($diff[$i] != '' && substr($diff[$i], 0, 1) != ' ') {
+                    break;
+                }
+                $array[] = substr($diff[$i++], 2);
+            }
+            while ($j < $max_j && ($max_i-$i) <= 1) {
+                if ($diff[$j] != '' && substr($diff[$j], 0, 1) != ' ') {
+                    break;
+                }
+                $array[] = substr($diff[$j++], 2);
+            }
+            if (count($array) > 0) {
+                $edits[] = &new Text_Diff_Op_copy($array);
+            }
+
+            if ($i < $max_i) {
+                $diff1 = array();
+                switch (substr($diff[$i], 0, 1)) {
+                case '!':
+                    $diff2 = array();
+                    do {
+                        $diff1[] = substr($diff[$i], 2);
+                        if ($j < $max_j && substr($diff[$j], 0, 1) == '!') {
+                            $diff2[] = substr($diff[$j++], 2);
+                        }
+                    } while (++$i < $max_i && substr($diff[$i], 0, 1) == '!');
+                    $edits[] = &new Text_Diff_Op_change($diff1, $diff2);
+                    break;
+                case '+':
+                    do {
+                        $diff1[] = substr($diff[$i], 2);
+                    } while (++$i < $max_i && substr($diff[$i], 0, 1) == '+');
+                    $edits[] = &new Text_Diff_Op_add($diff1);
+                    break;
+                case '-':
+                    do {
+                        $diff1[] = substr($diff[$i], 2);
+                    } while (++$i < $max_i && substr($diff[$i], 0, 1) == '-');
+                    $edits[] = &new Text_Diff_Op_delete($diff1);
+                    break;
+                }
+            }
+
+            if ($j < $max_j) {
+                $diff2 = array();
+                switch (substr($diff[$j], 0, 1)) {
+                case '+':
+                    do {
+                        $diff2[] = substr($diff[$j++], 2);
+                    } while ($j < $max_j && substr($diff[$j], 0, 1) == '+');
+                    $edits[] = &new Text_Diff_Op_add($diff2);
+                    break;
+                case '-':
+                    do {
+                        $diff2[] = substr($diff[$j++], 2);
+                    } while ($j < $max_j && substr($diff[$j], 0, 1) == '-');
+                    $edits[] = &new Text_Diff_Op_delete($diff2);
+                    break;
+                }
+            }
+        }
+        return $edits;
+    }
+}