fix getPrettySizeBytes does not return requested unit if a lower unit is more appropriate

core/Metrics/Formatter.php

@@ -134,10 +134,15 @@ class Formatter
         }
 
         $units = array('B', 'K', 'M', 'G', 'T');
+        $numUnits = count($units) - 1;
 
         $currentUnit = null;
         foreach ($units as $idx => $currentUnit) {
-            if ($size >= 1024 && $unit != $currentUnit && $idx != count($units) - 1) {
+            if ($unit && $unit !== $currentUnit) {
+                $size = $size / 1024;
+            } elseif ($unit && $unit === $currentUnit) {
+                break;
+            } elseif ($size >= 1024 && $idx != $numUnits) {
                 $size = $size / 1024;
             } else {
                 break;

tests/PHPUnit/Unit/Metrics/Formatter/HtmlTest.php

@@ -61,6 +61,22 @@ class HtmlTest extends \PHPUnit_Framework_TestCase
         $this->assertEquals($expected, $value);
     }
 
+    public function test_getPrettySizeFromBytes_InFixedUnitThatIsHigherThanBestUnit()
+    {
+        $expected = '0.001465 M';
+        $value = $this->formatter->getPrettySizeFromBytes(1536, 'M', 6);
+
+        $this->assertEquals($expected, $value);
+    }
+
+    public function test_getPrettySizeFromBytes_InUnitThatIsLowerThanBestUnit()
+    {
+        $expected = '1536 B';
+        $value = $this->formatter->getPrettySizeFromBytes(1536, 'B');
+
+        $this->assertEquals($expected, $value);
+    }
+
     public function test_getPrettyMoney_UsesNonBreakingSpaces()
     {
         $expected = '1 €';