diff --git a/test/classes/PMA_DBQbe_test.php b/test/classes/PMA_DBQbe_test.php
index 0e408b203d..6985cdc83b 100644
--- a/test/classes/PMA_DBQbe_test.php
+++ b/test/classes/PMA_DBQbe_test.php
@@ -99,7 +99,10 @@ class PMA_DBQbe_test extends PHPUnit_Framework_TestCase
      * Test for getCommonFunctions
      */
     public function testGetCommonFunctions(){
-        $this->assertTrue($this->object->getCommonFunctions() instanceof PMA_CommonFunctions);
+        $this->assertInstanceOf(
+            'PMA_CommonFunctions',
+            $this->object->getCommonFunctions()
+        );
     }
 
     /**
diff --git a/test/classes/PMA_DbSearch_test.php b/test/classes/PMA_DbSearch_test.php
index 4bcb52bd8e..1d3b0e4087 100644
--- a/test/classes/PMA_DbSearch_test.php
+++ b/test/classes/PMA_DbSearch_test.php
@@ -76,7 +76,10 @@ class PMA_DbSearch_test extends PHPUnit_Framework_TestCase
      * Test for getCommonFunctions
      */
     public function testGetCommonFunctions(){
-        $this->assertTrue($this->object->getCommonFunctions() instanceof PMA_CommonFunctions);
+        $this->assertInstanceOf(
+            'PMA_CommonFunctions',
+            $this->object->getCommonFunctions()
+        );
     }
 
     /**
diff --git a/test/classes/PMA_Theme_Manager_test.php b/test/classes/PMA_Theme_Manager_test.php
index 7e20d743cd..8b7c897ca3 100644
--- a/test/classes/PMA_Theme_Manager_test.php
+++ b/test/classes/PMA_Theme_Manager_test.php
@@ -101,7 +101,10 @@ class PMA_Theme_Manager_test extends PHPUnit_Framework_TestCase
      */
     public function testGetFallBackTheme(){
         $tm = new PMA_Theme_Manager();
-        $this->assertTrue($tm->getFallBackTheme() instanceof PMA_Theme);
+        $this->assertInstanceOf(
+            'PMA_theme',
+            $tm->getFallBackTheme()
+        );
     }
 
 }
diff --git a/test/classes/gis/PMA_GIS_Geometrycollection_test.php b/test/classes/gis/PMA_GIS_Geometrycollection_test.php
index 0ea797bdeb..7b7e640fc9 100644
--- a/test/classes/gis/PMA_GIS_Geometrycollection_test.php
+++ b/test/classes/gis/PMA_GIS_Geometrycollection_test.php
@@ -236,7 +236,7 @@ class PMA_GIS_Geometrycollection_test extends PHPUnit_Framework_TestCase
         $return = $this->object->prepareRowAsPdf(
             $spatial, $label, $line_color, $scale_data, $pdf
         );
-        $this->assertTrue($return instanceof TCPDF);
+        $this->assertInstanceOf('TCPDF', $return);
     }
 
     public function providerForPrepareRowAsPdf()
diff --git a/test/classes/gis/PMA_GIS_Linestring_test.php b/test/classes/gis/PMA_GIS_Linestring_test.php
index 6a12feaa85..eb2530df22 100644
--- a/test/classes/gis/PMA_GIS_Linestring_test.php
+++ b/test/classes/gis/PMA_GIS_Linestring_test.php
@@ -220,7 +220,7 @@ class PMA_GIS_LinestringTest extends PMA_GIS_GeomTest
         $return = $this->object->prepareRowAsPdf(
             $spatial, $label, $line_color, $scale_data, $pdf
         );
-        $this->assertTrue($return instanceof TCPDF);
+        $this->assertInstanceOf('TCPDF', $return);
     }
 
     public function providerForPrepareRowAsPdf()
diff --git a/test/classes/gis/PMA_GIS_Multilinestring_test.php b/test/classes/gis/PMA_GIS_Multilinestring_test.php
index 7547d634ea..30e52a8343 100644
--- a/test/classes/gis/PMA_GIS_Multilinestring_test.php
+++ b/test/classes/gis/PMA_GIS_Multilinestring_test.php
@@ -276,7 +276,7 @@ class PMA_GIS_MultilinestringTest extends PMA_GIS_GeomTest
     {
 
         $return = $this->object->prepareRowAsPdf($spatial, $label, $line_color, $scale_data, $pdf);
-        $this->assertTrue($return instanceof TCPDF);
+        $this->assertInstanceOf('TCPDF', $return);
     }
 
     public function providerForPrepareRowAsPdf(){
diff --git a/test/classes/gis/PMA_GIS_Multipoint_test.php b/test/classes/gis/PMA_GIS_Multipoint_test.php
index eaff4559e2..5e94d24641 100644
--- a/test/classes/gis/PMA_GIS_Multipoint_test.php
+++ b/test/classes/gis/PMA_GIS_Multipoint_test.php
@@ -220,7 +220,7 @@ class PMA_GIS_MultipointTest extends PMA_GIS_GeomTest
     {
 
         $return = $this->object->prepareRowAsPdf($spatial, $label, $line_color, $scale_data, $pdf);
-        $this->assertTrue($return instanceof TCPDF);
+        $this->assertInstanceOf('TCPDF', $return);
     }
 
     public function providerForPrepareRowAsPdf(){
diff --git a/test/classes/gis/PMA_GIS_Multipolygon_test.php b/test/classes/gis/PMA_GIS_Multipolygon_test.php
index c62959a43e..821db4ce8a 100644
--- a/test/classes/gis/PMA_GIS_Multipolygon_test.php
+++ b/test/classes/gis/PMA_GIS_Multipolygon_test.php
@@ -314,7 +314,7 @@ class PMA_GIS_MultipolygonTest extends PMA_GIS_GeomTest
     {
 
         $return = $this->object->prepareRowAsPdf($spatial, $label, $line_color, $scale_data, $pdf);
-        $this->assertTrue($return instanceof TCPDF);
+        $this->assertInstanceOf('TCPDF', $return);
     }
 
     public function providerForPrepareRowAsPdf(){
diff --git a/test/classes/gis/PMA_GIS_Point_test.php b/test/classes/gis/PMA_GIS_Point_test.php
index 35908d7f35..f218640ab4 100644
--- a/test/classes/gis/PMA_GIS_Point_test.php
+++ b/test/classes/gis/PMA_GIS_Point_test.php
@@ -222,7 +222,7 @@ class PMA_GIS_PointTest extends PMA_GIS_GeomTest
     {
 
         $return = $this->object->prepareRowAsPdf($spatial, $label, $line_color, $scale_data, $pdf);
-        $this->assertTrue($return instanceof TCPDF);
+        $this->assertInstanceOf('TCPDF', $return);
     }
 
     public function providerForPrepareRowAsPdf(){
diff --git a/test/classes/gis/PMA_GIS_Polygon_test.php b/test/classes/gis/PMA_GIS_Polygon_test.php
index 1b852c8d71..1c15749269 100644
--- a/test/classes/gis/PMA_GIS_Polygon_test.php
+++ b/test/classes/gis/PMA_GIS_Polygon_test.php
@@ -402,7 +402,7 @@ class PMA_GIS_PolygonTest extends PMA_GIS_GeomTest
     {
 
         $return = $this->object->prepareRowAsPdf($spatial, $label, $line_color, $scale_data, $pdf);
-        $this->assertTrue($return instanceof TCPDF);
+        $this->assertInstanceOf('TCPDF', $return);
     }
 
     public function providerForPrepareRowAsPdf(){