Better PSR-3 message formatting

src/Monolog/Processor/PsrLogMessageProcessor.php

@@ -20,7 +20,7 @@ namespace Monolog\Processor;
  */
 class PsrLogMessageProcessor
 {
-    const SIMPLE_DATE = "Y-m-d\TH:i:sP";
+    const SIMPLE_DATE = "Y-m-d\TH:i:s.uP";
 
     private $dateFormat;
 
@@ -60,6 +60,8 @@ class PsrLogMessageProcessor
                 $replacements[$placeholder] = $val->format($this->dateFormat);
             } elseif (is_object($val)) {
                 $replacements[$placeholder] = '[object '.get_class($val).']';
+            } elseif (is_array($val)) {
+                $replacements[$placeholder] = 'array'.@json_encode($val);
             } else {
                 $replacements[$placeholder] = '['.gettype($val).']';
             }

tests/Monolog/Processor/PsrLogMessageProcessorTest.php

@@ -68,7 +68,11 @@ class PsrLogMessageProcessorTest extends \PHPUnit\Framework\TestCase
             [false,    ''],
             [$date, $date->format(PsrLogMessageProcessor::SIMPLE_DATE)],
             [new \stdClass, '[object stdClass]'],
-            [[], '[array]'],
+            [[], 'array[]'],
+            [[], 'array[]'],
+            [[1, 2, 3], 'array[1,2,3]'],
+            [['foo' => 'bar'], 'array{"foo":"bar"}'],
+            [stream_context_create(), '[resource]'],
         ];
     }
 }