Add TextTypeDefaultStringExtension with associated configuration setting

README.md

@@ -28,6 +28,7 @@ return [
 ## Features
 
 - [Rate Limiter Attributes](#rate-limiter-attributes)
+- [Form Text Fields Empty String](#form-text-fields-empty-string)
 
 ### Rate Limiter Attributes
 
@@ -82,6 +83,24 @@ headsnet_symfony_tools:
 
 Thanks to [this JoliCode article](https://jolicode.com/blog/rate-limit-your-symfony-apis) for the inspiration!
 
+### Form Text Fields Empty String
+
+By default Symfony uses `null` as the default value for text-based form fields. This results in `null` values being all 
+over the codebase. 
+
+An easy way to fix this is to change the default behaviour so text-based fields return an empty string 
+`''` instead of `null`. Then, class properties can be typed `string` instead of `string|null` and this 
+can eliminate a lot of null checks in the client code.
+
+This is an opinionated solution, so must be enabled in the bundle configuration:
+
+```yaml
+headsnet_symfony_tools:
+  forms:
+    default_empty_string:
+      enabled: true
+```
+
 ## License
 
 Released under the [MIT License](LICENSE).

composer.json

@@ -13,6 +13,7 @@
     "symfony/config": "^6.0 || ^7.0",
     "symfony/dependency-injection": "^6.0 || ^7.0",
     "symfony/event-dispatcher": "^6.0 || ^7.0",
+    "symfony/form": "^6.0 || ^7.0",
     "symfony/http-kernel": "^6.0 || ^7.0",
     "symfony/lock": "^6.0 || ^7.0",
     "symfony/rate-limiter": "^6.0 || ^7.0"

src/Form/Extension/TextTypeDefaultStringExtension.php

@@ -0,0 +1,34 @@
+<?php
+declare(strict_types=1);
+
+namespace Headsnet\SymfonyToolsBundle\Form\Extension;
+
+use Symfony\Component\Form\AbstractTypeExtension;
+use Symfony\Component\Form\Extension\Core\Type\EmailType;
+use Symfony\Component\Form\Extension\Core\Type\TextareaType;
+use Symfony\Component\Form\Extension\Core\Type\TextType;
+use Symfony\Component\Form\Extension\Core\Type\UrlType;
+use Symfony\Component\OptionsResolver\OptionsResolver;
+
+/**
+ * Override the default behaviour of TextType, which returns null when the field is empty.
+ *
+ * To keep our entities free of nulls, we want to return an empty string instead. This
+ * extension simply sets the "empty_data" option to "" for all TextType fields.
+ */
+final class TextTypeDefaultStringExtension extends AbstractTypeExtension
+{
+    #[\Override]
+    public static function getExtendedTypes(): iterable
+    {
+        return [TextType::class, EmailType::class, UrlType::class, TextareaType::class];
+    }
+
+    #[\Override]
+    public function configureOptions(OptionsResolver $resolver): void
+    {
+        parent::configureOptions($resolver);
+
+        $resolver->setDefault('empty_data', '');
+    }
+}

src/HeadsnetSymfonyToolsBundle.php

@@ -2,6 +2,7 @@
 
 namespace Headsnet\SymfonyToolsBundle;
 
+use Headsnet\SymfonyToolsBundle\Form\Extension\TextTypeDefaultStringExtension;
 use Headsnet\SymfonyToolsBundle\RateLimiting\RateLimitingCompilerPass;
 use Symfony\Component\Config\Definition\Configurator\DefinitionConfigurator;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
@@ -20,13 +21,26 @@ public function configure(DefinitionConfigurator $definition): void
                         ->booleanNode('use_headers')->end()
                     ->end()
                 ->end() // End rate_limiting
+            ->arrayNode('forms')
+                ->addDefaultsIfNotSet()
+                ->children()
+                    ->arrayNode('default_empty_string')
+                        ->canBeEnabled()
+                    ->end() // End default_empty_string
+                ->end()
+            ->end() // End forms
             ->end()
         ;
     }
 
     /**
      * @param array{
      *     root_namespace: string,
+     *     forms: array{
+     *         default_empty_string: array{
+     *             enabled: bool
+     *         }
+     *     },
      *     rate_limiting: array{use_headers: bool}
      * } $config
      */
@@ -38,6 +52,15 @@ public function loadExtension(array $config, ContainerConfigurator $container, C
             ->set('headsnet_symfony_tools.root_namespace', $config['root_namespace'])
             ->set('headsnet_symfony_tools.rate_limiting.use_headers', $config['rate_limiting']['use_headers'])
         ;
+
+        if ($config['forms']['default_empty_string']['enabled']) {
+            $container->services()
+                ->set('headsnet_symfony_tools.forms.default_empty_string_extension')
+                ->class(TextTypeDefaultStringExtension::class)
+                ->tag('form.type_extension')
+                ->public()
+            ;
+        }
     }
 
     public function build(ContainerBuilder $container): void

tests/Fixtures/config.yaml

@@ -1,5 +1,8 @@
 headsnet_symfony_tools:
-  root_namespace: App
-  rate_limiting:
-    use_headers: true
+    root_namespace: App
+    forms:
+      default_empty_string:
+        enabled: true
+    rate_limiting:
+        use_headers: true
 

tests/Form/Extension/TextTypeDefaultStringExtensionTest.php

@@ -0,0 +1,43 @@
+<?php
+declare(strict_types=1);
+
+namespace Headsnet\SymfonyToolsBundle\Tests\Form\Extension;
+
+use Headsnet\SymfonyToolsBundle\Form\Extension\TextTypeDefaultStringExtension;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\Test;
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\Form\Extension\Core\Type\EmailType;
+use Symfony\Component\Form\Extension\Core\Type\TextareaType;
+use Symfony\Component\Form\Extension\Core\Type\TextType;
+use Symfony\Component\Form\Extension\Core\Type\UrlType;
+use Symfony\Component\OptionsResolver\OptionsResolver;
+
+#[CoversClass(TextTypeDefaultStringExtension::class)]
+final class TextTypeDefaultStringExtensionTest extends TestCase
+{
+    #[Test]
+    public function applies_to_all_textual_form_types(): void
+    {
+        $result = TextTypeDefaultStringExtension::getExtendedTypes();
+
+        $this->assertEquals([TextType::class, EmailType::class, UrlType::class, TextareaType::class], $result);
+    }
+
+    #[Test]
+    public function validation_is_disabled(): void
+    {
+        $optionsResolver = new OptionsResolver();
+        $sut = new TextTypeDefaultStringExtension();
+
+        $sut->configureOptions($optionsResolver);
+
+        $this->assertTrue($optionsResolver->isDefined('empty_data'));
+        $this->assertEquals(
+            [
+                'empty_data' => '',
+            ],
+            $optionsResolver->resolve()
+        );
+    }
+}

tests/HeadsnetSymfonyToolsBundleTest.php

@@ -45,5 +45,9 @@ public function initialise_bundle(): void
         $this->assertTrue(
             $container->hasParameter('headsnet_symfony_tools.rate_limiting.use_headers')
         );
+
+        $this->assertNotNull(
+            $container->get('headsnet_symfony_tools.forms.default_empty_string_extension')
+        );
     }
 }