From 89c87a15e98dceb6b6b1d0ad0834c4e8e64f639b Mon Sep 17 00:00:00 2001
From: Javier Eguiluz <javier.eguiluz@gmail.com>
Date: Mon, 12 Mar 2018 16:36:02 +0100
Subject: [PATCH 1/4] Documented the "values" option of the Expression
 constraint

---
 reference/constraints/Expression.rst | 88 ++++++++++++++++++++++++++++
 1 file changed, 88 insertions(+)

diff --git a/reference/constraints/Expression.rst b/reference/constraints/Expression.rst
index 7408b7bbb55..e0d3e638932 100644
--- a/reference/constraints/Expression.rst
+++ b/reference/constraints/Expression.rst
@@ -12,6 +12,7 @@ gives you similar flexibility.
 | Options        | - :ref:`expression <reference-constraint-expression-option>`                                  |
 |                | - `message`_                                                                                  |
 |                | - `payload`_                                                                                  |
+|                | - `values`_                                                                                   |
 +----------------+-----------------------------------------------------------------------------------------------+
 | Class          | :class:`Symfony\\Component\\Validator\\Constraints\\Expression`                               |
 +----------------+-----------------------------------------------------------------------------------------------+
@@ -253,3 +254,90 @@ message
 The default message supplied when the expression evaluates to false.
 
 .. include:: /reference/constraints/_payload-option.rst.inc
+
+values
+~~~~~~
+
+**type**: ``array`` **default**: an empty array
+
+.. versionadded:: 4.1
+    The ``values`` option was introduced in Symfony 4.1.
+
+The values of the custom variables used in the expression.
+
+.. configuration-block::
+
+    .. code-block:: php-annotations
+
+        // src/Model/Analysis.php
+        namespace App\Model;
+
+        use Symfony\Component\Validator\Constraints as Assert;
+
+        class Analysis
+        {
+            // ...
+
+            /**
+             * @Assert\Expression(
+             *     "value + error_margin < threshold",
+             *     values = { "error_margin": 0.25, threshold: 1.5 }
+             * )
+             */
+            private $metric;
+
+            // ...
+        }
+
+    .. code-block:: yaml
+
+        # config/validator/validation.yaml
+        App\Model\Analysis:
+            properties:
+                metric:
+                    - Expression:
+                        expression: "value + error_margin < threshold"
+                        values:     { error_margin: 0.25, threshold: 1.5 }
+
+    .. code-block:: xml
+
+        <!-- config/validator/validation.xml -->
+        <?xml version="1.0" encoding="UTF-8" ?>
+        <constraint-mapping xmlns="http://symfony.com/schema/dic/constraint-mapping"
+            xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+            xsi:schemaLocation="http://symfony.com/schema/dic/constraint-mapping http://symfony.com/schema/dic/constraint-mapping/constraint-mapping-1.0.xsd">
+
+            <class name="App\Model\Analysis">
+                <property name="metric">
+                    <constraint name="Expression">
+                        <option name="expression">
+                            value + error_margin < threshold
+                        </option>
+                        <option name="values">
+                            ... ?
+                        </option>
+                    </constraint>
+                </property>
+            </class>
+        </constraint-mapping>
+
+    .. code-block:: php
+
+        // src/Model/Analysis.php
+        namespace App\Model;
+
+        use Symfony\Component\Validator\Constraints as Assert;
+        use Symfony\Component\Validator\Mapping\ClassMetadata;
+
+        class Analysis
+        {
+            public static function loadValidatorMetadata(ClassMetadata $metadata)
+            {
+                $metadata->addPropertyConstraint('metric', new Assert\Expression(array(
+                    'expression' => 'value + error_margin < threshold',
+                    'values' => array('error_margin' => 0.25, 'threshold' => 1.5),
+                )));
+            }
+
+            // ...
+        }

From a87c55ffaf3105bb3966038c16a69808e0bb82ac Mon Sep 17 00:00:00 2001
From: Javier Eguiluz <javier.eguiluz@gmail.com>
Date: Mon, 12 Mar 2018 17:37:36 +0100
Subject: [PATCH 2/4] Tried to fix the XML example

---
 reference/constraints/Expression.rst | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/reference/constraints/Expression.rst b/reference/constraints/Expression.rst
index e0d3e638932..3a0448dadda 100644
--- a/reference/constraints/Expression.rst
+++ b/reference/constraints/Expression.rst
@@ -263,7 +263,8 @@ values
 .. versionadded:: 4.1
     The ``values`` option was introduced in Symfony 4.1.
 
-The values of the custom variables used in the expression.
+The values of the custom variables used in the expression. Values can be of any
+type (numeric, boolean, strings, null, etc.)
 
 .. configuration-block::
 
@@ -311,10 +312,11 @@ The values of the custom variables used in the expression.
                 <property name="metric">
                     <constraint name="Expression">
                         <option name="expression">
-                            value + error_margin < threshold
+                            value + error_margin &lt; threshold
                         </option>
                         <option name="values">
-                            ... ?
+                            <value key="error_margin">0.25</value>
+                            <value key="threshold">1.5</value>
                         </option>
                     </constraint>
                 </property>

From 1e9041693aa81c35bd55b388c67d4300028b1ae3 Mon Sep 17 00:00:00 2001
From: Javier Eguiluz <javier.eguiluz@gmail.com>
Date: Wed, 14 Mar 2018 13:18:48 +0100
Subject: [PATCH 3/4] Tweaks after review

---
 reference/constraints/Expression.rst | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/reference/constraints/Expression.rst b/reference/constraints/Expression.rst
index 3a0448dadda..b9a352259ef 100644
--- a/reference/constraints/Expression.rst
+++ b/reference/constraints/Expression.rst
@@ -258,7 +258,7 @@ The default message supplied when the expression evaluates to false.
 values
 ~~~~~~
 
-**type**: ``array`` **default**: an empty array
+**type**: ``array`` **default**: ``[]``
 
 .. versionadded:: 4.1
     The ``values`` option was introduced in Symfony 4.1.
@@ -277,8 +277,6 @@ type (numeric, boolean, strings, null, etc.)
 
         class Analysis
         {
-            // ...
-
             /**
              * @Assert\Expression(
              *     "value + error_margin < threshold",

From 0aa0ce304554642fe93f11f048cfbb5d8938c065 Mon Sep 17 00:00:00 2001
From: Javier Eguiluz <javier.eguiluz@gmail.com>
Date: Sun, 18 Mar 2018 19:42:26 +0100
Subject: [PATCH 4/4] Minor tweak

---
 reference/constraints/Expression.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/reference/constraints/Expression.rst b/reference/constraints/Expression.rst
index b9a352259ef..80a9f0bed4a 100644
--- a/reference/constraints/Expression.rst
+++ b/reference/constraints/Expression.rst
@@ -280,7 +280,7 @@ type (numeric, boolean, strings, null, etc.)
             /**
              * @Assert\Expression(
              *     "value + error_margin < threshold",
-             *     values = { "error_margin": 0.25, threshold: 1.5 }
+             *     values = { "error_margin": 0.25, "threshold": 1.5 }
              * )
              */
             private $metric;