Add class() and addClass() methods to DropdownFilter

src/Filter/Widget/DropdownFilter.php

@@ -4,6 +4,7 @@
 
 namespace Yiisoft\Yii\DataView\Filter\Widget;
 
+use BackedEnum;
 use Yiisoft\Html\Tag\Select;
 
 /**
@@ -90,6 +91,30 @@ public function attributes(array $attributes): self
         return $new;
     }
 
+    /**
+     * Add one or more CSS classes to the `Select` tag.
+     *
+     * @param BackedEnum|string|null ...$class One or many CSS classes.
+     */
+    public function addClass(BackedEnum|string|null ...$class): self
+    {
+        $new = clone $this;
+        $new->select = $this->getSelect()->addClass(...$class);
+        return $new;
+    }
+
+    /**
+     * Replace current `Select` tag CSS classes with a new set of classes.
+     *
+     * @param BackedEnum|string|null ...$class One or many CSS classes.
+     */
+    public function class(BackedEnum|string|null ...$class): self
+    {
+        $new = clone $this;
+        $new->select = $this->getSelect()->class(...$class);
+        return $new;
+    }
+
     /**
      * Renders the dropdown filter with the given context.
      *

tests/Filter/Widget/DropdownFilterTest.php

@@ -4,9 +4,12 @@
 
 namespace Yiisoft\Yii\DataView\Tests\Filter\Widget;
 
+use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\TestCase;
 use Yiisoft\Yii\DataView\Filter\Widget\Context;
 use Yiisoft\Yii\DataView\Filter\Widget\DropdownFilter;
+use Yiisoft\Yii\DataView\Tests\Support\IntegerEnum;
+use Yiisoft\Yii\DataView\Tests\Support\StringEnum;
 
 /**
  * @covers \Yiisoft\Yii\DataView\Filter\Widget\DropdownFilter
@@ -88,4 +91,78 @@ public function testAttributes(): void
         $this->assertStringContainsString('class="new-select"', $html);
         $this->assertStringContainsString('required', $html);
     }
+
+    public static function dataAddClass(): array
+    {
+        return [
+            ['<select class="main" name="status"', []],
+            ['<select class="main" name="status"', ['main']],
+            ['<select class="main bold" name="status"', ['bold']],
+            ['<select class="main italic bold" name="status"', ['italic bold']],
+            ['<select class="main italic bold" name="status"', ['italic', 'bold']],
+            ['<select class="main test-class-1 test-class-2" name="status"', [StringEnum::TEST_CLASS_1, StringEnum::TEST_CLASS_2]],
+            [
+                '<select class="main test-class-1 test-class-2" name="status"',
+                [IntegerEnum::A, StringEnum::TEST_CLASS_1, IntegerEnum::B, StringEnum::TEST_CLASS_2],
+            ],
+        ];
+    }
+
+    #[DataProvider('dataAddClass')]
+    public function testAddClass(string $expected, array $class): void
+    {
+        $context = new Context('status', null, 'filter-form');
+        $html = DropdownFilter::widget()
+            ->addClass('main')
+            ->addClass(...$class)
+            ->renderFilter($context);
+        $this->assertStringContainsString($expected, $html);
+    }
+
+    public static function dataNewClass(): array
+    {
+        return [
+            ['<select name="status"', null],
+            ['<select class name="status"', ''],
+            ['<select class="red" name="status"', 'red'],
+        ];
+    }
+
+    #[DataProvider('dataNewClass')]
+    public function testNewClass(string $expected, ?string $class): void
+    {
+        $context = new Context('status', null, 'filter-form');
+        $html = DropdownFilter::widget()
+            ->addClass($class)
+            ->renderFilter($context);
+        $this->assertStringContainsString($expected, $html);
+    }
+
+    public static function dataClass(): array
+    {
+        return [
+            ['<select name="status"', []],
+            ['<select name="status"', [null]],
+            ['<select class name="status"', ['']],
+            ['<select class="main" name="status"', ['main']],
+            ['<select class="main bold" name="status"', ['main bold']],
+            ['<select class="main bold" name="status"', ['main', 'bold']],
+            ['<select class="test-class-1 test-class-2" name="status"', [StringEnum::TEST_CLASS_1, StringEnum::TEST_CLASS_2]],
+            [
+                'class="test-class-1 test-class-2" name="status"',
+                [IntegerEnum::A, StringEnum::TEST_CLASS_1, IntegerEnum::B, StringEnum::TEST_CLASS_2],
+            ],
+        ];
+    }
+
+    #[DataProvider('dataClass')]
+    public function testClass(string $expected, array $class): void
+    {
+        $context = new Context('status', null, 'filter-form');
+        $html = DropdownFilter::widget()
+            ->class('red')
+            ->class(...$class)
+            ->renderFilter($context);
+        $this->assertStringContainsString($expected, $html);
+    }
 }

tests/Support/IntegerEnum.php

@@ -0,0 +1,12 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Yiisoft\Yii\DataView\Tests\Support;
+
+enum IntegerEnum: int
+{
+    case A = 1;
+    case B = 2;
+    case C = 3;
+}

tests/Support/StringEnum.php

@@ -0,0 +1,11 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Yiisoft\Yii\DataView\Tests\Support;
+
+enum StringEnum: string
+{
+    case TEST_CLASS_1 = 'test-class-1';
+    case TEST_CLASS_2 = 'test-class-2';
+}