Add first unit test

src/Monolog/BreadcrumbHandler.php

@@ -44,7 +44,6 @@ public function __construct(HubInterface $hub, $level = Logger::DEBUG, bool $bub
      *      channel: string,
      *      datetime: \DateTimeImmutable,
      *      message: string,
-     *      formatted?: string,
      *      extra?: array<string, mixed>
      * } $record {@see https://github.com/Seldaek/monolog/blob/main/doc/message-structure.md}
      */
@@ -54,7 +53,7 @@ protected function write(array $record): void
             $this->getBreadcrumbLevel($record['level']),
             $this->getBreadcrumbType($record['level']),
             $record['channel'],
-            $record['formatted'] ?? $record['message'],
+            $record['message'],
             $record['extra'] ?? [],
             $record['datetime']->getTimestamp()
         );

tests/Monolog/BreadcrumbHandlerTest.php

@@ -0,0 +1,64 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Sentry\Tests\Monolog;
+
+use Monolog\Logger;
+use PHPUnit\Framework\TestCase;
+use Sentry\Breadcrumb;
+use Sentry\Monolog\BreadcrumbHandler;
+use Sentry\State\HubInterface;
+
+final class BreadcrumbHandlerTest extends TestCase
+{
+    /**
+     * @dataProvider handleDataProvider
+     */
+    public function testHandle(array $record, Breadcrumb $expectedBreadcrumb): void
+    {
+        $hub = $this->createMock(HubInterface::class);
+        $hub->expects($this->once())
+            ->method('addBreadcrumb')
+            ->with($this->callback(function (Breadcrumb $breadcrumb) use ($expectedBreadcrumb): bool {
+                $this->assertSame($expectedBreadcrumb->getMessage(), $breadcrumb->getMessage());
+                $this->assertSame($expectedBreadcrumb->getLevel(), $breadcrumb->getLevel());
+                $this->assertSame($expectedBreadcrumb->getType(), $breadcrumb->getType());
+                $this->assertSame($expectedBreadcrumb->getTimestamp(), $breadcrumb->getTimestamp());
+                $this->assertSame($expectedBreadcrumb->getCategory(), $breadcrumb->getCategory());
+                $this->assertEquals($expectedBreadcrumb->getMetadata(), $breadcrumb->getMetadata());
+
+                return true;
+            }));
+
+        $handler = new BreadcrumbHandler($hub);
+        $handler->handle($record);
+    }
+
+    public function handleDataProvider(): iterable
+    {
+        $defaultData = [
+            'message' => 'foo bar',
+            'level' => Logger::DEBUG,
+            'level_name' => Logger::getLevelName(Logger::DEBUG),
+            'channel' => 'channel.foo',
+            'context' => [],
+            'extra' => [],
+            'datetime' => new \DateTimeImmutable(),
+        ];
+
+        $defaultBreadcrumb = new Breadcrumb(
+            Breadcrumb::LEVEL_DEBUG,
+            Breadcrumb::TYPE_DEFAULT,
+            'channel.foo',
+            'foo bar',
+            [],
+            $defaultData['datetime']->getTimestamp()
+        );
+
+        yield [
+            $defaultData,
+            $defaultBreadcrumb,
+        ];
+    }
+}