minor #35847 [Notifier] Add unit tests (jschaedl)

This PR was merged into the 5.0 branch.

Discussion
----------

[Notifier] Add unit tests

| Q             | A
| ------------- | ---
| Branch?       | 5.0
| Bug fix?      | no
| New feature?  | no <!-- please update src/**/CHANGELOG.md files -->
| Deprecations? | no <!-- please update UPGRADE-*.md and src/**/CHANGELOG.md files -->
| Tickets       | - <!-- prefix each issue number with "Fix #", if any -->
| License       | MIT
| Doc PR        | - <!-- required for new features -->

- [x] `AbstractChannel`
- [x] `ChannelPolicy`
- [x] `RecipientTest` (done in PR #35773)
- [x] `EmailRecipientTest` (done in PR #35773)
- [x] `SmsRecipientTest` (done in PR #35773)
- [x] `Transports` (see PR #35834)

Commits
-------

022c1707e2 [Notifier] Add tests for AbstractChannel and ChannelPolicy

src/Symfony/Component/Notifier/Tests/Channel/AbstractChannelTest.php

@@ -0,0 +1,44 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Notifier\Tests\Channel;
+
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\Notifier\Channel\AbstractChannel;
+use Symfony\Component\Notifier\Exception\LogicException;
+use Symfony\Component\Notifier\Notification\Notification;
+use Symfony\Component\Notifier\Recipient\Recipient;
+
+/**
+ * @author Jan Schädlich <jan.schaedlich@sensiolabs.de>
+ */
+class AbstractChannelTest extends TestCase
+{
+    public function testChannelCannotBeConstructedWithoutTransportAndBus()
+    {
+        $this->expectException(LogicException::class);
+
+        new DummyChannel();
+    }
+}
+
+class DummyChannel extends AbstractChannel
+{
+    public function notify(Notification $notification, Recipient $recipient, string $transportName = null): void
+    {
+        return;
+    }
+
+    public function supports(Notification $notification, Recipient $recipient): bool
+    {
+        return false;
+    }
+}

src/Symfony/Component/Notifier/Tests/Channel/ChannelPolicyTest.php

@@ -0,0 +1,48 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Notifier\Tests\Channel;
+
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\Notifier\Channel\ChannelPolicy;
+use Symfony\Component\Notifier\Exception\InvalidArgumentException;
+
+/**
+ * @author Jan Schädlich <jan.schaedlich@sensiolabs.de>
+ */
+class ChannelPolicyTest extends TestCase
+{
+    public function testCannotRetrieveChannelsUsingUnavailableImportance()
+    {
+        $this->expectException(InvalidArgumentException::class);
+
+        $channelPolicy = new ChannelPolicy(['urgent' => ['chat']]);
+        $channelPolicy->getChannels('low');
+    }
+
+    /**
+     * @dataProvider provideValidPolicies
+     */
+    public function testCanRetrieveChannels(array $policy, string $importance, array $expectedChannels)
+    {
+        $channelPolicy = new ChannelPolicy($policy);
+        $channels = $channelPolicy->getChannels($importance);
+
+        $this->assertSame($expectedChannels, $channels);
+    }
+
+    public function provideValidPolicies(): \Generator
+    {
+        yield [['urgent' => ['chat']], 'urgent', ['chat']];
+        yield [['urgent' => ['chat', 'sms']], 'urgent', ['chat', 'sms']];
+        yield [['urgent' => ['chat', 'chat/slack', 'sms']], 'urgent', ['chat', 'chat/slack', 'sms']];
+    }
+}