From f61eea9169e05c00dcf24aee7b96c8f4ff8f2972 Mon Sep 17 00:00:00 2001
From: Marcel Kapfer <opensource@mmk2410.org>
Date: Thu, 16 Sep 2021 22:45:25 +0200
Subject: [PATCH] PHPunit example

---
 src/Email.php       | 33 +++++++++++++++++++++++++++++++++
 tests/EmailTest.php | 27 +++++++++++++++++++++++++++
 2 files changed, 60 insertions(+)
 create mode 100644 src/Email.php
 create mode 100644 tests/EmailTest.php

diff --git a/src/Email.php b/src/Email.php
new file mode 100644
index 0000000..ac3c74d
--- /dev/null
+++ b/src/Email.php
@@ -0,0 +1,33 @@
+<?php declare(strict_types=1);
+
+namespace MMK2410\MyTodoList;
+
+final class Email
+{
+    private $email;
+
+    private function __construct(string $email)
+    {
+        $this->ensureIsValidEmail($email);
+        $this->email = $email;
+    }
+
+    public static function fromString(string $email): self
+    {
+        return new self($email);
+    }
+
+    public function __toString(): string
+    {
+        return $this->email;
+    }
+
+    private function ensureIsValidEmail(string $email): void
+    {
+        if(!filter_var($email, FILTER_VALIDATE_EMAIL)) {
+            throw new \InvalidArgumentException(
+                sprintf("%s is not a valid email address", $email)
+            );
+        }
+    }
+}
diff --git a/tests/EmailTest.php b/tests/EmailTest.php
new file mode 100644
index 0000000..696af28
--- /dev/null
+++ b/tests/EmailTest.php
@@ -0,0 +1,27 @@
+<?php declare(strict_types=1);
+use PHPUnit\Framework\TestCase;
+use MMK2410\MyTodoList\Email;
+
+final class EmailTest extends TestCase
+{
+    private $email = 'user@example.com';
+
+    public function testCanBeCreatedFromValidEmailAddress(): void {
+        $this->assertInstanceOf(
+            Email::class,
+            Email::fromString($this->email)
+        );
+    }
+
+    public function testCannotBeCreatedFromInvalidEmailAddress(): void {
+        $this->expectException(InvalidArgumentException::class);
+        Email::fromString('invalid');
+    }
+
+    public function testCanBeUsedAsString(): void {
+        $this->assertEquals(
+            $this->email,
+            Email::fromString($this->email)
+        );
+    }
+}