Merge branch '5.4' into 6.2

* 5.4:
  Update environment processor page
  [Uid] Fix Uid config example
  Add Form is_empty_callback option

Author: javiereguiluz

components/uid.rst

@@ -100,9 +100,9 @@ configure the behavior of the factory using configuration files::
             uid:
                 default_uuid_version: 6
                 name_based_uuid_version: 5
-                name_based_uuid_namespace: ~
+                name_based_uuid_namespace: 6ba7b810-9dad-11d1-80b4-00c04fd430c8
                 time_based_uuid_version: 6
-                time_based_uuid_node: ~
+                time_based_uuid_node: 121212121212
 
     .. code-block:: xml
 
@@ -119,9 +119,9 @@ configure the behavior of the factory using configuration files::
                 <framework:uid
                     default_uuid_version="6"
                     name_based_uuid_version="5"
-                    name_based_uuid_namespace=""
+                    name_based_uuid_namespace="6ba7b810-9dad-11d1-80b4-00c04fd430c8"
                     time_based_uuid_version="6"
-                    time_based_uuid_node=""
+                    time_based_uuid_node="121212121212"
                 />
             </framework:config>
         </container>
@@ -141,9 +141,9 @@ configure the behavior of the factory using configuration files::
                 'uid' => [
                     'default_uuid_version' => 6,
                     'name_based_uuid_version' => 5,
-                    'name_based_uuid_namespace' => '',
+                    'name_based_uuid_namespace' => '6ba7b810-9dad-11d1-80b4-00c04fd430c8',
                     'time_based_uuid_version' => 6,
-                    'time_based_uuid_node' => '',
+                    'time_based_uuid_node' => 121212121212,
                 ],
             ]);
         };

configuration/env_var_processors.rst

@@ -441,7 +441,7 @@ Symfony provides the following env var processors:
 
             # config/packages/framework.yaml
             parameters:
-                env(AUTH_FILE): '../config/auth.json'
+                env(AUTH_FILE): '%kernel.project_dir%/config/auth.json'
             google:
                 auth: '%env(file:AUTH_FILE)%'
 
@@ -482,7 +482,7 @@ Symfony provides the following env var processors:
 
             # config/packages/framework.yaml
             parameters:
-                env(PHP_FILE): '../config/.runtime-evaluated.php'
+                env(PHP_FILE): '%kernel.project_dir%/config/.runtime-evaluated.php'
             app:
                 auth: '%env(require:PHP_FILE)%'
 
@@ -524,7 +524,7 @@ Symfony provides the following env var processors:
 
             # config/packages/framework.yaml
             parameters:
-                env(AUTH_FILE): '../config/auth.json'
+                env(AUTH_FILE): '%kernel.project_dir%/config/auth.json'
             google:
                 auth: '%env(trim:file:AUTH_FILE)%'
 

reference/forms/types/form.rst

@@ -64,6 +64,13 @@ The actual default value of this option depends on other field options:
 * If ``data_class`` is not set and ``compound`` is ``false``, then ``''``
   (empty string).
 
+``is_empty_callback``
+~~~~~~~~~~~~~~~~~~~~~
+
+**type**: ``callable`` **default**: ``null``
+
+This callable takes form data and returns whether value is considered empty.
+
 .. include:: /reference/forms/types/options/empty_data_description.rst.inc
 
 .. _reference-form-option-error-bubbling: