diff --git a/includes/common.inc b/includes/common.inc
index 5c645c7..534bf3b 100644
--- a/includes/common.inc
+++ b/includes/common.inc
@@ -4805,21 +4805,20 @@ function drupal_clear_js_cache() {
  * @ingroup php_wrappers
  */
 function drupal_json_encode($var) {
-  // We do not want to use drupal_static() since the PHP version will never
-  // change during a request.
+  // PHP version cannot change within a request.
   static $php530;
 
   if (!isset($php530)) {
     $php530 = version_compare(PHP_VERSION, '5.3.0', '>=');
   }
 
-  // json_encode on PHP prior to PHP 5.3.0 doesn't support options.
   if ($php530) {
-    // json_encode() escapes <, >, ', &, and " using its options parameter.
+    // Encode <, >, ', &, and " using the json_encode() options parameter.
     return json_encode($var, JSON_HEX_TAG | JSON_HEX_APOS | JSON_HEX_AMP | JSON_HEX_QUOT);
   }
 
-  // In PHP versions less than 5.3.0, use our helper.
+  // json_encode() escapes <, >, ', &, and " using its options parameter, but
+  // does not support this parameter prior to PHP 5.3.0.  Use a helper instead.
   return drupal_json_encode_helper($var);
 }
 
@@ -4832,9 +4831,11 @@ function drupal_json_encode_helper($var) {
   switch (gettype($var)) {
     case 'boolean':
       return $var ? 'true' : 'false'; // Lowercase necessary!
+
     case 'integer':
     case 'double':
       return $var;
+
     case 'resource':
     case 'string':
       // Always use Unicode escape sequences (\u0022) over JSON escape
@@ -4885,30 +4886,33 @@ function drupal_json_encode_helper($var) {
         // non-compliant JSON parsers from interpreting // as a comment.
         '/' => '\u002F',
         // While these are allowed unescaped according to ECMA-262, section
-        // 15.12.2, they cause problems in some JSON parser.
+        // 15.12.2, they cause problems in some JSON parsers.
         "\xe2\x80\xa8" => '\u2028', // U+2028, Line Separator.
         "\xe2\x80\xa9" => '\u2029', // U+2029, Paragraph Separator.
       );
 
-      return '"'. strtr($var, $replace_pairs) .'"';
+      return '"' . strtr($var, $replace_pairs) . '"';
+
     case 'array':
       // Arrays in JSON can't be associative. If the array is empty or if it
       // has sequential whole number keys starting with 0, it's not associative
       // so we can go ahead and convert it as an array.
-      if (empty ($var) || array_keys($var) === range(0, sizeof($var) - 1)) {
+      if (empty($var) || array_keys($var) === range(0, sizeof($var) - 1)) {
         $output = array();
         foreach ($var as $v) {
           $output[] = drupal_json_encode_helper($v);
         }
-        return '[ '. implode(', ', $output) .' ]';
+        return '[ ' . implode(', ', $output) . ' ]';
       }
       // Otherwise, fall through to convert the array as an object.
+
     case 'object':
       $output = array();
       foreach ($var as $k => $v) {
         $output[] = drupal_json_encode_helper(strval($k)) . ':' . drupal_json_encode_helper($v);
       }
-      return '{'. implode(', ', $output) .'}';
+      return '{' . implode(', ', $output) . '}';
+
     default:
       return 'null';
   }
diff --git a/modules/taxonomy/taxonomy.test b/modules/taxonomy/taxonomy.test
index 4e9eb2c..597bfc3 100644
--- a/modules/taxonomy/taxonomy.test
+++ b/modules/taxonomy/taxonomy.test
@@ -627,8 +627,8 @@ class TaxonomyTermTestCase extends TaxonomyWebTestCase {
     }
     $this->assertNoText($term1->name, t('The deleted term %name does not appear on the node page.', array('%name' => $term1->name)));
 
-    // Test autocomplete on term 2 - it contains a comma, so expect the key to
-    // be quoted.
+    // Test autocomplete on term 2, which contains a comma.
+    // The term will be quoted, and the " will be encoded in unicode (\u0022).
     $input = substr($term2->name, 0, 3);
     $this->drupalGet('taxonomy/autocomplete/taxonomy_' . $this->vocabulary->machine_name . '/' . $input);
     $this->assertRaw('{"\u0022' . $term2->name . '\u0022":"' . $term2->name . '"}', t('Autocomplete returns term %term_name after typing the first 3 letters.', array('%term_name' => $term2->name)));