- Patch #765860 by effulgentsia, dww, dereine, mikey_p, xjm, sun, sven.lauer: drupal_alter() fails to order modules correctly in some cases.

1 files changed, 9 insertions, 0 deletions

diff --git a/modules/system/system.api.php b/modules/system/system.api.php
index 1e8d35a78..7ffdae4ea 100644
--- a/modules/system/system.api.php
+++ b/modules/system/system.api.php
@@ -1877,6 +1877,15 @@ function hook_mail_alter(&$message) {
  * hook in order to reorder the implementing modules, which are otherwise
  * ordered by the module's system weight.
  *
+ * Note that hooks invoked using drupal_alter() can have multiple variations
+ * (such as hook_form_alter() and hook_form_FORM_ID_alter()). drupal_alter()
+ * will call all such variants defined by a single module in turn. For the
+ * purposes of hook_module_implements_alter(), these variants are treated as
+ * a single hook. Thus, to ensure that your implementation of
+ * hook_form_FORM_ID_alter() is called at the right time, you will have to
+ * have to change the order of hook_form_alter() implementation in
+ * hook_module_implements_alter().
+ *
  * @param $implementations
  *   An array keyed by the module's name. The value of each item corresponds
  *   to a $group, which is usually FALSE, unless the implementation is in a