Create IsNull rule

docs/03-rules.md

@@ -12,6 +12,7 @@
 
 - [Blank](03-rules_blank.md)
 - [Count](03-rules_count.md)
+- [IsNull](03-rules_is-null.md)
 - [NotBlank](03-rules_not-blank.md)
 - [Type](03-rules_type.md)
 

docs/03-rules_is-null.md

@@ -0,0 +1,35 @@
+# IsNull
+
+Validates that a value is `null`.
+
+```php
+IsNull(
+    ?string $message = null
+);
+```
+
+## Basic Usage
+
+```php
+// anything else will be false
+Validator::isNull()->validate(null); // true
+```
+
+## Options
+
+### `message`
+
+type: `?string` default: `The {{ name }} value should be null, {{ value }} given.`
+
+Message that will be shown if the value is null.
+
+The following parameters are available:
+
+| Parameter     | Description               |
+|---------------|---------------------------|
+| `{{ value }}` | The current invalid value |
+| `{{ name }}`  | Name of the invalid value |
+
+## Changelog
+
+- `1.3.0` Created

src/ChainedValidatorInterface.php

@@ -80,6 +80,10 @@ public function greaterThanOrEqual(
         ?string $message = null
     ): ChainedValidatorInterface&Validator;
 
+    public function isNull(
+        ?string $message = null
+    ): ChainedValidatorInterface&Validator;
+
     public function language(
         string $code = 'alpha-2',
         ?string $message = null

src/Exception/IsNullException.php

@@ -0,0 +1,5 @@
+<?php
+
+namespace ProgrammatorDev\Validator\Exception;
+
+class IsNullException extends ValidationException {}

src/Rule/IsNull.php

@@ -0,0 +1,30 @@
+<?php
+
+namespace ProgrammatorDev\Validator\Rule;
+
+use ProgrammatorDev\Validator\Exception\IsNullException;
+
+class IsNull extends AbstractRule implements RuleInterface
+{
+    private string $message = 'The {{ name }} value should be null, {{ value }} given.';
+
+    public function __construct(
+        ?string $message = null
+    )
+    {
+        $this->message = $message ?? $this->message;
+    }
+
+    public function assert(mixed $value, ?string $name = null): void
+    {
+        if (!\is_null($value)) {
+            throw new IsNullException(
+                message: $this->message,
+                parameters: [
+                    'value' => $value,
+                    'name' => $name
+                ]
+            );
+        }
+    }
+}

src/StaticValidatorInterface.php

@@ -79,6 +79,10 @@ public static function greaterThanOrEqual(
         ?string $message = null
     ): ChainedValidatorInterface&Validator;
 
+    public static function isNull(
+        ?string $message = null
+    ): ChainedValidatorInterface&Validator;
+
     public static function language(
         string $code = 'alpha-2',
         ?string $message = null

src/Validator.php

@@ -6,12 +6,13 @@
 use ProgrammatorDev\Validator\Exception\UnexpectedValueException;
 use ProgrammatorDev\Validator\Exception\ValidationException;
 use ProgrammatorDev\Validator\Factory\Factory;
+use ProgrammatorDev\Validator\Rule\AbstractRule;
 use ProgrammatorDev\Validator\Rule\RuleInterface;
 
 /**
  * @mixin StaticValidatorInterface
  */
-class Validator implements RuleInterface
+class Validator extends AbstractRule implements RuleInterface
 {
     /** @var RuleInterface[] */
     private array $rules;
@@ -59,18 +60,6 @@ public function assert(mixed $value, ?string $name = null): void
         }
     }
 
-    public function validate(mixed $value): bool
-    {
-        try {
-            $this->assert($value);
-        }
-        catch (ValidationException) {
-            return false;
-        }
-
-        return true;
-    }
-
     public function getRules(): array
     {
         return $this->rules;

tests/IsNullTest.php

@@ -0,0 +1,43 @@
+<?php
+
+namespace ProgrammatorDev\Validator\Test;
+
+use ProgrammatorDev\Validator\Exception\IsNullException;
+use ProgrammatorDev\Validator\Rule\IsNull;
+use ProgrammatorDev\Validator\Test\Util\TestRuleFailureConditionTrait;
+use ProgrammatorDev\Validator\Test\Util\TestRuleMessageOptionTrait;
+use ProgrammatorDev\Validator\Test\Util\TestRuleSuccessConditionTrait;
+
+class IsNullTest extends AbstractTest
+{
+    use TestRuleFailureConditionTrait;
+    use TestRuleSuccessConditionTrait;
+    use TestRuleMessageOptionTrait;
+
+    public static function provideRuleFailureConditionData(): \Generator
+    {
+        $exception = IsNullException::class;
+        $message = '/The (.*) value should be null, (.*) given\./';
+
+        yield 'int' => [new IsNull(), 1, $exception, $message];
+        yield 'string' => [new IsNull(), 'string', $exception, $message];
+        yield 'bool' => [new IsNull(), true, $exception, $message];
+        yield 'array' => [new IsNull(), [], $exception, $message];
+    }
+
+    public static function provideRuleSuccessConditionData(): \Generator
+    {
+        yield 'null' => [new IsNull(), null];
+    }
+
+    public static function provideRuleMessageOptionData(): \Generator
+    {
+        yield 'message' => [
+            new IsNull(
+                message: '{{ name }} | {{ value }}'
+            ),
+            'string',
+            'test | "string"'
+        ];
+    }
+}