Index: includes/actions.inc
===================================================================
RCS file: /cvs/drupal/drupal/includes/actions.inc,v
retrieving revision 1.39
diff -u -r1.39 actions.inc
--- includes/actions.inc	22 Aug 2010 11:04:09 -0000	1.39
+++ includes/actions.inc	25 Oct 2010 14:04:19 -0000
@@ -278,7 +278,7 @@
     // user adds the action.
     if (!$array['configurable']) {
       // If we already have an action ID for this action, no need to assign aid.
-      if (array_key_exists($callback, $actions_in_db)) {
+      if (isset($actions_in_db[$callback])) {
         unset($actions_in_db[$callback]);
       }
       else {
Index: includes/tablesort.inc
===================================================================
RCS file: /cvs/drupal/drupal/includes/tablesort.inc,v
retrieving revision 1.59
diff -u -r1.59 tablesort.inc
--- includes/tablesort.inc	15 Oct 2010 04:34:15 -0000	1.59
+++ includes/tablesort.inc	25 Oct 2010 14:04:19 -0000
@@ -80,7 +80,7 @@
     // User has not specified a sort. Use default if specified; otherwise use "asc".
     else {
       foreach ($this->header as $header) {
-        if (is_array($header) && array_key_exists('sort', $header)) {
+        if (isset($header['sort'])) {
           return $header['sort'];
         }
       }
@@ -279,7 +279,7 @@
   // User has not specified a sort. Use default if specified; otherwise use "asc".
   else {
     foreach ($headers as $header) {
-      if (is_array($header) && array_key_exists('sort', $header)) {
+      if (isset($header['sort'])) {
         return $header['sort'];
       }
     }
Index: includes/theme.inc
===================================================================
RCS file: /cvs/drupal/drupal/includes/theme.inc,v
retrieving revision 1.620
diff -u -r1.620 theme.inc
--- includes/theme.inc	21 Oct 2010 19:31:39 -0000	1.620
+++ includes/theme.inc	25 Oct 2010 14:04:19 -0000
@@ -402,7 +402,7 @@
       // that themes don't need to specify this information, since the module
       // that registered the theme hook already has.
       foreach (array('variables', 'render element', 'pattern', 'base hook') as $key) {
-        if (!array_key_exists($key, $info) && isset($cache[$hook][$key])) {
+        if (!isset($info[$key]) && isset($cache[$hook][$key])) {
           $result[$hook][$key] = $cache[$hook][$key];
         }
       }
Index: includes/database/pgsql/schema.inc
===================================================================
RCS file: /cvs/drupal/drupal/includes/database/pgsql/schema.inc,v
retrieving revision 1.39
diff -u -r1.39 schema.inc
--- includes/database/pgsql/schema.inc	22 Oct 2010 15:18:56 -0000	1.39
+++ includes/database/pgsql/schema.inc	25 Oct 2010 14:04:19 -0000
@@ -469,9 +469,7 @@
       throw new DatabaseSchemaObjectExistsException(t("Cannot rename field %table.%name to %name_new: target field already exists.", array('%table' => $table, '%name' => $field, '%name_new' => $field_new)));
     }
 
-    if (!array_key_exists('size', $spec)) {
-      $spec['size'] = 'normal';
-    }
+    $spec += array('size' => 'normal');
 
     // Map type definition to the PostgreSQL type.
     if (!isset($spec['pgsql_type'])) {
Index: modules/block/block.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/block/block.module,v
retrieving revision 1.431
diff -u -r1.431 block.module
--- modules/block/block.module	28 Sep 2010 03:30:37 -0000	1.431
+++ modules/block/block.module	25 Oct 2010 14:04:19 -0000
@@ -607,7 +607,7 @@
     $result = db_query("SELECT * FROM {block} WHERE theme = :theme", array(':theme' => $default_theme), array('fetch' => PDO::FETCH_ASSOC));
     foreach ($result as $block) {
       // If the region isn't supported by the theme, assign the block to the theme's default region.
-      if ($block['status'] && !array_key_exists($block['region'], $regions)) {
+      if ($block['status'] && !isset($regions[$block['region']])) {
         $block['region'] = system_default_region($theme);
       }
       $block['theme'] = $theme;
Index: modules/comment/comment.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/comment/comment.module,v
retrieving revision 1.907
diff -u -r1.907 comment.module
--- modules/comment/comment.module	23 Oct 2010 15:30:34 -0000	1.907
+++ modules/comment/comment.module	25 Oct 2010 14:04:19 -0000
@@ -2287,7 +2287,8 @@
     if (!isset($authenticated_post_comments)) {
       // We only output a link if we are certain that users will get permission
       // to post comments by logging in.
-      $authenticated_post_comments = array_key_exists(DRUPAL_AUTHENTICATED_RID, user_roles(TRUE, 'post comments') + user_roles(TRUE, 'skip comment approval'));
+      $comment_roles = user_roles(TRUE, 'post comments') + user_roles(TRUE, 'skip comment approval');
+      $authenticated_post_comments = isset($comment_roles[DRUPAL_AUTHENTICATED_RID]);
     }
 
     if ($authenticated_post_comments) {
Index: modules/field/modules/list/list.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/field/modules/list/list.module,v
retrieving revision 1.35
diff -u -r1.35 list.module
--- modules/field/modules/list/list.module	11 Oct 2010 19:57:00 -0000	1.35
+++ modules/field/modules/list/list.module	25 Oct 2010 14:04:19 -0000
@@ -261,7 +261,7 @@
   $allowed_values = list_allowed_values($field);
   foreach ($items as $delta => $item) {
     if (!empty($item['value'])) {
-      if (count($allowed_values) && !array_key_exists($item['value'], $allowed_values)) {
+      if (!empty($allowed_values) && !isset($allowed_values[$item['value']])) {
         $errors[$field['field_name']][$langcode][$delta][] = array(
           'error' => 'list_illegal_value',
           'message' => t('%name: illegal value.', array('%name' => t($instance['label']))),
Index: modules/field_ui/field_ui.admin.inc
===================================================================
RCS file: /cvs/drupal/drupal/modules/field_ui/field_ui.admin.inc,v
retrieving revision 1.80
diff -u -r1.80 field_ui.admin.inc
--- modules/field_ui/field_ui.admin.inc	23 Oct 2010 15:55:04 -0000	1.80
+++ modules/field_ui/field_ui.admin.inc	25 Oct 2010 14:04:20 -0000
@@ -54,7 +54,7 @@
       $list[] = t('%field (@field_name) field requires the %widget_type widget provided by %widget_module module', array(
       '%field' => $instance['label'],
       '@field_name' => $instance['field_name'],
-      '%widget_type' => array_key_exists($instance['widget']['type'], $widget_types) ? $widget_types[$instance['widget']['type']]['label'] : $instance['widget']['type'],
+      '%widget_type' => isset($widget_types[$instance['widget']['type']]) ? $widget_types[$instance['widget']['type']]['label'] : $instance['widget']['type'],
       '%widget_module' => $instance['widget']['module'],
       ));
     }
Index: modules/filter/filter.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/filter/filter.module,v
retrieving revision 1.355
diff -u -r1.355 filter.module
--- modules/filter/filter.module	22 Oct 2010 16:36:14 -0000	1.355
+++ modules/filter/filter.module	25 Oct 2010 14:04:20 -0000
@@ -1301,14 +1301,12 @@
   $header = array(t('Tag Description'), t('You Type'), t('You Get'));
   preg_match_all('/<([a-z0-9]+)[^a-z0-9]/i', $allowed_html, $out);
   foreach ($out[1] as $tag) {
-    if (array_key_exists($tag, $tips)) {
-      if ($tips[$tag]) {
-        $rows[] = array(
-          array('data' => $tips[$tag][0], 'class' => array('description')),
-          array('data' => '<code>' . check_plain($tips[$tag][1]) . '</code>', 'class' => array('type')),
-          array('data' => $tips[$tag][1], 'class' => array('get'))
-        );
-      }
+    if (!empty($tips[$tag])) {
+      $rows[] = array(
+        array('data' => $tips[$tag][0], 'class' => array('description')),
+        array('data' => '<code>' . check_plain($tips[$tag][1]) . '</code>', 'class' => array('type')),
+        array('data' => $tips[$tag][1], 'class' => array('get'))
+      );
     }
     else {
       $rows[] = array(
Index: modules/openid/openid.inc
===================================================================
RCS file: /cvs/drupal/drupal/modules/openid/openid.inc,v
retrieving revision 1.36
diff -u -r1.36 openid.inc
--- modules/openid/openid.inc	22 Aug 2010 22:00:16 -0000	1.36
+++ modules/openid/openid.inc	25 Oct 2010 14:04:20 -0000
@@ -501,7 +501,7 @@
   // Used as the key for the duplicate cache
   $rbytes = _openid_dh_long_to_binary($stop);
 
-  if (array_key_exists($rbytes, $duplicate_cache)) {
+  if (isset($duplicate_cache[$rbytes])) {
     list($duplicate, $nbytes) = $duplicate_cache[$rbytes];
   }
   else {
Index: modules/openid/openid.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/openid/openid.module,v
retrieving revision 1.96
diff -u -r1.96 openid.module
--- modules/openid/openid.module	24 Sep 2010 00:37:43 -0000	1.96
+++ modules/openid/openid.module	25 Oct 2010 14:04:20 -0000
@@ -932,7 +932,7 @@
   // contains a number of other parameters added by the OpenID Provider.
   parse_str(isset($return_to_parts['query']) ? $return_to_parts['query'] : '', $return_to_query_parameters);
   foreach ($return_to_query_parameters as $name => $value) {
-    if (!array_key_exists($name, $_GET) || $_GET[$name] != $value) {
+    if (!isset($_GET[$name]) || $_GET[$name] != $value) {
       return FALSE;
     }
   }
Index: modules/profile/profile.admin.inc
===================================================================
RCS file: /cvs/drupal/drupal/modules/profile/profile.admin.inc,v
retrieving revision 1.43
diff -u -r1.43 profile.admin.inc
--- modules/profile/profile.admin.inc	20 Oct 2010 01:31:07 -0000	1.43
+++ modules/profile/profile.admin.inc	25 Oct 2010 14:04:20 -0000
@@ -126,7 +126,7 @@
   $category_number = 0;
   foreach (element_children($form) as $key) {
     // Don't take form control structures.
-    if (array_key_exists('category', $form[$key])) {
+    if (isset($form[$key]['category'])) {
       $field = &$form[$key];
       $category = $field['category']['#default_value'];
 
Index: modules/system/image.gd.inc
===================================================================
RCS file: /cvs/drupal/drupal/modules/system/image.gd.inc,v
retrieving revision 1.17
diff -u -r1.17 image.gd.inc
--- modules/system/image.gd.inc	21 Sep 2010 15:28:11 -0000	1.17
+++ modules/system/image.gd.inc	25 Oct 2010 14:04:20 -0000
@@ -351,7 +351,7 @@
 
   if (isset($data) && is_array($data)) {
     $extensions = array('1' => 'gif', '2' => 'jpg', '3' => 'png');
-    $extension = array_key_exists($data[2], $extensions) ?  $extensions[$data[2]] : '';
+    $extension = isset($extensions[$data[2]]) ?  $extensions[$data[2]] : '';
     $details = array(
       'width'     => $data[0],
       'height'    => $data[1],
Index: modules/system/system.api.php
===================================================================
RCS file: /cvs/drupal/drupal/modules/system/system.api.php,v
retrieving revision 1.206
diff -u -r1.206 system.api.php
--- modules/system/system.api.php	23 Oct 2010 15:30:34 -0000	1.206
+++ modules/system/system.api.php	25 Oct 2010 14:04:20 -0000
@@ -2627,7 +2627,7 @@
     // Serve files with one of the CDN extensions from CDN 1, all others from
     // CDN 2.
     $pathinfo = pathinfo($path);
-    if (array_key_exists('extension', $pathinfo) && in_array($pathinfo['extension'], $cdn_extensions)) {
+    if (isset($pathinfo['extension']) && in_array($pathinfo['extension'], $cdn_extensions)) {
       $uri = $cdn1 . '/' . $path;
     }
     else {