From 2c3a7cc532a8a2fa5c0b81a2b5a6469e05d65024 Mon Sep 17 00:00:00 2001
From: Ener-Getick <egetick@gmail.com>
Date: Mon, 1 Feb 2016 20:26:57 +0100
Subject: [PATCH] Deprecate using Form::isValid() with an unsubmitted form

---
 UPGRADE-3.2.md                                | 22 +++++++++++++++++++
 UPGRADE-4.0.md                                | 19 ++++++++++++++++
 src/Symfony/Component/Form/Form.php           |  2 ++
 src/Symfony/Component/Form/FormInterface.php  |  2 +-
 .../Component/Form/Tests/SimpleFormTest.php   |  5 ++++-
 5 files changed, 48 insertions(+), 2 deletions(-)

diff --git a/UPGRADE-3.2.md b/UPGRADE-3.2.md
index 211d9f253626..741958a5ff54 100644
--- a/UPGRADE-3.2.md
+++ b/UPGRADE-3.2.md
@@ -7,6 +7,28 @@ DependencyInjection
  * Calling `get()` on a `ContainerBuilder` instance before compiling the
    container is deprecated and will throw an exception in Symfony 4.0.
 
+Form
+----
+
+ * Calling `isValid()` on a `Form` instance before submitting it
+   is deprecated and will throw an exception in Symfony 4.0.
+
+   Before:
+
+   ```php
+   if ($form->isValid()) {
+       // ...
+   }
+   ```
+
+   After:
+
+   ```php
+   if ($form->isSubmitted() && $form->isValid()) {
+       // ...
+   }
+   ```
+
 Validator
 ---------
 
diff --git a/UPGRADE-4.0.md b/UPGRADE-4.0.md
index 3687b0b78248..53ecad9e1dfb 100644
--- a/UPGRADE-4.0.md
+++ b/UPGRADE-4.0.md
@@ -42,6 +42,25 @@ Form
  * Caching of the loaded `ChoiceListInterface` in the `LazyChoiceList` has been removed,
    it must be cached in the `ChoiceLoaderInterface` implementation instead.
 
+ * Calling `isValid()` on a `Form` instance before submitting it is not supported
+   anymore and raises an exception.
+
+   Before:
+
+   ```php
+   if ($form->isValid()) {
+       // ...
+   }
+   ```
+
+   After:
+
+   ```php
+   if ($form->isSubmitted() && $form->isValid()) {
+       // ...
+   }
+   ```
+
 FrameworkBundle
 ---------------
 
diff --git a/src/Symfony/Component/Form/Form.php b/src/Symfony/Component/Form/Form.php
index 74ff45b297dc..3d29abe9124d 100644
--- a/src/Symfony/Component/Form/Form.php
+++ b/src/Symfony/Component/Form/Form.php
@@ -724,6 +724,8 @@ public function isEmpty()
     public function isValid()
     {
         if (!$this->submitted) {
+            @trigger_error('Call Form::isValid() with an unsubmitted form is deprecated since version 3.2 and will throw an exception in 4.0. Use Form::isSubmitted() before Form::isValid() instead.', E_USER_DEPRECATED);
+
             return false;
         }
 
diff --git a/src/Symfony/Component/Form/FormInterface.php b/src/Symfony/Component/Form/FormInterface.php
index b2131e1da4ec..83fd70a84807 100644
--- a/src/Symfony/Component/Form/FormInterface.php
+++ b/src/Symfony/Component/Form/FormInterface.php
@@ -192,7 +192,7 @@ public function addError(FormError $error);
     /**
      * Returns whether the form and all children are valid.
      *
-     * If the form is not submitted, this method always returns false.
+     * If the form is not submitted, this method always returns false (but will throw an exception in 4.0).
      *
      * @return bool
      */
diff --git a/src/Symfony/Component/Form/Tests/SimpleFormTest.php b/src/Symfony/Component/Form/Tests/SimpleFormTest.php
index 36edea5da983..d4d74c28d0f8 100644
--- a/src/Symfony/Component/Form/Tests/SimpleFormTest.php
+++ b/src/Symfony/Component/Form/Tests/SimpleFormTest.php
@@ -11,6 +11,7 @@
 
 namespace Symfony\Component\Form\Tests;
 
+use Symfony\Bridge\PhpUnit\ErrorAssert;
 use Symfony\Component\Form\Form;
 use Symfony\Component\Form\FormEvent;
 use Symfony\Component\Form\FormEvents;
@@ -315,7 +316,9 @@ public function testValidIfSubmittedAndDisabled()
 
     public function testNotValidIfNotSubmitted()
     {
-        $this->assertFalse($this->form->isValid());
+        ErrorAssert::assertDeprecationsAreTriggered(array('Call Form::isValid() with an unsubmitted form'), function () {
+            $this->assertFalse($this->form->isValid());
+        });
     }
 
     public function testNotValidIfErrors()