add possibility to translate exception messages

src/Gtin/NonNormalizable.php

@@ -3,7 +3,9 @@
 
 namespace Real\Validator\Gtin;
 
-class NonNormalizable extends \InvalidArgumentException
+use Real\Validator\UserError;
+
+class NonNormalizable extends \InvalidArgumentException implements UserError
 {
     # @formatter:off
     public const CODE_LENGTH_14         = 1000;
@@ -17,21 +19,25 @@ class NonNormalizable extends \InvalidArgumentException
     /** @var string */
     private $value;
 
+    /** @var int */
+    private $reasonCode;
+
     public function __construct(string $value, Specification $specification, \Throwable $previous = null)
     {
         $this->value = $value;
+        $this->reasonCode = $specification->reasonCode();
 
-        parent::__construct($this->reasonMessage($specification), $specification->reasonCode(), $previous);
+        parent::__construct($this->reasonMessage($this->reasonCode), $this->reasonCode, $previous);
     }
 
     public function value(): string
     {
         return $this->value;
     }
 
-    private function reasonMessage(Specification $specification): string
+    private function reasonMessage(int $reasonCode): string
     {
-        switch ($specification->reasonCode()) {
+        switch ($reasonCode) {
             case self::CODE_LENGTH_14:
                 $message = 'Length is greater than 14 characters';
                 break;
@@ -54,4 +60,20 @@ private function reasonMessage(Specification $specification): string
 
         return $message;
     }
+
+    /**
+     * @inheritdoc
+     */
+    public function messageKey(): string
+    {
+        return sprintf('GTIN %%gtin%% is not valid. %s', $this->getMessage());
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function messageData(): array
+    {
+        return ['%gtin%' => $this->value];
+    }
 }

src/UserError.php

@@ -0,0 +1,17 @@
+<?php
+declare(strict_types=1);
+
+namespace Real\Validator;
+
+interface UserError
+{
+    /**
+     * Message key to be used by translation component
+     */
+    public function messageKey(): string;
+
+    /**
+     * Message data to be used by translation component
+     */
+    public function messageData(): array;
+}

tests/Gtin/NonNormalizableTest.php

@@ -5,6 +5,7 @@
 
 use PHPUnit\Framework\TestCase;
 use Real\Validator\Gtin;
+use Real\Validator\UserError;
 
 class NonNormalizableTest extends TestCase
 {
@@ -30,13 +31,14 @@ public function testValue(string $value)
         self::assertSame($value, $exception->value());
     }
 
-    public function testExceptionExtendsTheBasicOne()
+    public function testInheritance()
     {
         /** @var Gtin\Specification $specification */
         $specification = $this->createMock(Gtin\Specification::class);
 
         $exception = new Gtin\NonNormalizable('string', $specification);
         self::assertInstanceOf(\InvalidArgumentException::class, $exception);
+        self::assertInstanceOf(UserError::class, $exception);
     }
 
     public function testConstantValues()
@@ -48,4 +50,24 @@ public function testConstantValues()
         self::assertSame(1004, Gtin\NonNormalizable::CODE_CHECKSUM);
         self::assertSame(1005, Gtin\NonNormalizable::CODE_PREFIX);
     }
+
+    public function testMessageKey()
+    {
+        /** @var Gtin\Specification $specification */
+        $specification = $this->createConfiguredMock(Gtin\Specification::class, ['reasonCode' => 42]);
+        $exception = new Gtin\NonNormalizable('123456789', $specification);
+
+        self::assertRegExp('/%gtin%/', $exception->messageKey());
+    }
+
+    public function testMessageData()
+    {
+        /** @var Gtin\Specification $specification */
+        $specification = $this->createConfiguredMock(Gtin\Specification::class, ['reasonCode' => 42]);
+        $exception = new Gtin\NonNormalizable('123456789', $specification);
+
+        $messageData = $exception->messageData();
+        self::assertArrayHasKey('%gtin%', $messageData);
+        self::assertSame('123456789', $messageData['%gtin%']);
+    }
 }