From ef5835d8336fe675fa1f1a8a35f9b7c9ae55ae7a Mon Sep 17 00:00:00 2001
From: Christian Flothmann <christian.flothmann@sensiolabs.de>
Date: Sat, 4 Jan 2020 09:15:56 +0100
Subject: [PATCH] derive the view timezone from the model timezone

---
 src/Symfony/Component/Form/CHANGELOG.md       |  1 +
 .../Form/Extension/Core/Type/TimeType.php     | 20 +++++++++++++++----
 .../Extension/Core/Type/TimeTypeTest.php      |  9 +++++++++
 3 files changed, 26 insertions(+), 4 deletions(-)

diff --git a/src/Symfony/Component/Form/CHANGELOG.md b/src/Symfony/Component/Form/CHANGELOG.md
index 6b207848dc76..82231b3c45c9 100644
--- a/src/Symfony/Component/Form/CHANGELOG.md
+++ b/src/Symfony/Component/Form/CHANGELOG.md
@@ -4,6 +4,7 @@ CHANGELOG
 5.1.0
 -----
 
+ * The `view_timezone` option defaults to the `model_timezone` if no `reference_date` is configured.
  * Added default `inputmode` attribute to Search, Email and Tel form types.
 
 5.0.0
diff --git a/src/Symfony/Component/Form/Extension/Core/Type/TimeType.php b/src/Symfony/Component/Form/Extension/Core/Type/TimeType.php
index ed683beeaf98..2e55a6d0b421 100644
--- a/src/Symfony/Component/Form/Extension/Core/Type/TimeType.php
+++ b/src/Symfony/Component/Form/Extension/Core/Type/TimeType.php
@@ -280,6 +280,18 @@ public function configureOptions(OptionsResolver $resolver)
             return null;
         };
 
+        $viewTimezone = static function (Options $options, $value): ?string {
+            if (null !== $value) {
+                return $value;
+            }
+
+            if (null !== $options['model_timezone'] && null === $options['reference_date']) {
+                return $options['model_timezone'];
+            }
+
+            return null;
+        };
+
         $resolver->setDefaults([
             'hours' => range(0, 23),
             'minutes' => range(0, 59),
@@ -290,7 +302,7 @@ public function configureOptions(OptionsResolver $resolver)
             'with_minutes' => true,
             'with_seconds' => false,
             'model_timezone' => $modelTimezone,
-            'view_timezone' => null,
+            'view_timezone' => $viewTimezone,
             'reference_date' => null,
             'placeholder' => $placeholderDefault,
             'html5' => true,
@@ -310,12 +322,12 @@ public function configureOptions(OptionsResolver $resolver)
             'choice_translation_domain' => false,
         ]);
 
-        $resolver->setNormalizer('model_timezone', function (Options $options, $modelTimezone): ?string {
-            if (null !== $modelTimezone && $options['view_timezone'] !== $modelTimezone && null === $options['reference_date']) {
+        $resolver->setNormalizer('view_timezone', function (Options $options, $viewTimezone): ?string {
+            if (null !== $options['model_timezone'] && $viewTimezone !== $options['model_timezone'] && null === $options['reference_date']) {
                 throw new LogicException(sprintf('Using different values for the "model_timezone" and "view_timezone" options without configuring a reference date is not supported.'));
             }
 
-            return $modelTimezone;
+            return $viewTimezone;
         });
 
         $resolver->setNormalizer('placeholder', $placeholderNormalizer);
diff --git a/src/Symfony/Component/Form/Tests/Extension/Core/Type/TimeTypeTest.php b/src/Symfony/Component/Form/Tests/Extension/Core/Type/TimeTypeTest.php
index f220bf97e8a6..25803308e952 100644
--- a/src/Symfony/Component/Form/Tests/Extension/Core/Type/TimeTypeTest.php
+++ b/src/Symfony/Component/Form/Tests/Extension/Core/Type/TimeTypeTest.php
@@ -859,6 +859,15 @@ public function testModelTimezoneDefaultToReferenceDateTimezoneIfProvided()
         $this->assertSame('Europe/Berlin', $form->getConfig()->getOption('model_timezone'));
     }
 
+    public function testViewTimezoneDefaultsToModelTimezoneIfProvided()
+    {
+        $form = $this->factory->create(static::TESTED_TYPE, null, [
+            'model_timezone' => 'Europe/Berlin',
+        ]);
+
+        $this->assertSame('Europe/Berlin', $form->getConfig()->getOption('view_timezone'));
+    }
+
     public function testPassDefaultChoiceTranslationDomain()
     {
         $form = $this->factory->create(static::TESTED_TYPE);