Add InMemoryLogger

src/InMemoryLogger.php

@@ -0,0 +1,48 @@
+<?php
+
+namespace SubjectivePHP\Psr\Log;
+
+use ArrayObject;
+use Psr\Log\AbstractLogger;
+use Psr\Log\LoggerInterface;
+
+/**
+ * PSR-3 Logger implementation writing to an array.
+ */
+final class InMemoryLogger extends AbstractLogger implements LoggerInterface
+{
+    use MessageInterpolationTrait;
+
+    /**
+     * @var ArrayObject
+     */
+    private $logs;
+
+    /**
+     * Construct a new instance of the logger.
+     *
+     * @param ArrayObject $logs Container for log entries.
+     */
+    public function __construct(ArrayObject $logs)
+    {
+        $this->logs = $logs;
+    }
+
+    /**
+     * Logs with an arbitrary level.
+     *
+     * @param string $level   A valid RFC-5424 log level.
+     * @param string $message The base log message.
+     * @param array  $context Any extraneous information that does not fit well in a string.
+     *
+     * @return void
+     */
+    public function log($level, $message, array $context = [])
+    {
+        $this->logs[] = [
+            'level' => $level,
+            'message' => $this->interpolateMessage($message, $context),
+            'context' => $context,
+        ];
+    }
+}

tests/InMemoryLoggerTest.php

@@ -0,0 +1,42 @@
+<?php
+
+namespace SubjectivePHPTest\Psr\Log;
+
+use ArrayObject;
+use PHPUnit\Framework\TestCase;
+use Psr\Log\LogLevel;
+use SubjectivePHP\Psr\Log\InMemoryLogger;
+
+/**
+ * @coversDefaultClass \SubjectivePHP\Psr\Log\InMemoryLogger
+ * @covers ::__construct
+ */
+final class InMeoryLoggerTest extends TestCase
+{
+    /**
+     * @test
+     * @covers ::log
+     *
+     * @return void
+     */
+    public function logAlertWithMessageInterpolation()
+    {
+        $exception = new \RuntimeException();
+        $logs = new ArrayObject();
+        $logger = new InMemoryLogger($logs);
+        $logger->alert('logged {count} entries', ['exception' => $exception, 'count' => 1]);
+        $this->assertSame(
+            [
+                [
+                    'level' => LogLevel::ALERT,
+                    'message' => 'logged 1 entries',
+                    'context' => [
+                        'exception' => $exception,
+                        'count' => 1,
+                    ],
+                ],
+            ],
+            $logs->getArrayCopy()
+        );
+    }
+}