Add wfUnserialize() wrapper around unserialize to prevent E_NOTICE and use it in ExifBitmap.php. There are probably many more places that could use this. This should fix Platonides' problem at r90421, but also added a check for $wgShowExif to prevent the test from failing.

includes/GlobalFunctions.php

@@ -3549,3 +3549,17 @@ function wfGetParserCacheStorage() {
 function wfRunHooks( $event, $args = array() ) {
 	return Hooks::run( $event, $args );
 }
+
+/**
+ * Unserialize a string to a PHP value without throwing E_NOTICE. Simply a 
+ * wrapper around unserialize()
+ * 
+ * @param $data string The serialized string
+ * @return mixed
+ */
+function wfUnserialize( $data ) {
+	wfSuppressWarnings();
+	$result = unserialize( $data );
+	wfRestoreWarnings();
+	return $result;
+}

includes/media/ExifBitmap.php

@@ -109,7 +109,7 @@ class ExifBitmapHandler extends BitmapHandler {
 			return false;
 		}
 
-		$exif = unserialize( $metadata );
+		$exif = wfUnserialize( $metadata );
 		if ( !$exif ) {
 			return false;
 		}

tests/phpunit/includes/GlobalFunctions.php/GlobalTest.php

@@ -879,6 +879,12 @@ class GlobalTest extends MediaWikiTestCase {
 			// are less consistent.
 		);
 	}
+	
+	public function testUnserialize() {
+		$this->assertEquals( '', wfUnserialize( 's:0:"";') );
+		$this->assertEquals( false, wfUnserialize( '0' ),
+			'Invalid input to unserialize()' );
+	}
 
 	/* TODO: many more! */
 }

tests/phpunit/includes/media/FormatMetadataTest.php

@@ -1,11 +1,17 @@
 <?php
 class FormatMetadataTest extends MediaWikiTestCase {
 	public function testInvalidDate() {
+		global $wgShowEXIF;
+		if ( !$wgShowEXIF ) {
+			$this->markTestIncomplete( "This test needs the exif extension." );
+		}
+		
 		$file = UnregisteredLocalFile::newFromPath( dirname( __FILE__ ) . 
 			'/broken_exif_date.jpg', 'image/jpeg' );
 		
 		// Throws an error if bug hit
 		$meta = $file->formatMetadata();
+		$this->assertNotEquals( false, $meta, 'Valid metadata extracted' );
 		
 		// Find date exif entry
 		$this->assertArrayHasKey( 'visible', $meta );