Use ::class keyword when possible

Author: fabpot

Tests/Caster/MemcachedCasterTest.php

@@ -23,7 +23,7 @@ class MemcachedCasterTest extends TestCase
 
     public function testCastMemcachedWithDefaultOptions()
     {
-        if (!class_exists('Memcached')) {
+        if (!class_exists(\Memcached::class)) {
             $this->markTestSkipped('Memcached not available');
         }
 
@@ -53,7 +53,7 @@ public function testCastMemcachedWithDefaultOptions()
 
     public function testCastMemcachedWithCustomOptions()
     {
-        if (!class_exists('Memcached')) {
+        if (!class_exists(\Memcached::class)) {
             $this->markTestSkipped('Memcached not available');
         }
 

Tests/Caster/PdoCasterTest.php

@@ -34,10 +34,10 @@ public function testCastPdo()
 
         $cast = PdoCaster::castPdo($pdo, [], new Stub(), false);
 
-        $this->assertInstanceOf('Symfony\Component\VarDumper\Caster\EnumStub', $cast["\0~\0attributes"]);
+        $this->assertInstanceOf(\Symfony\Component\VarDumper\Caster\EnumStub::class, $cast["\0~\0attributes"]);
 
         $attr = $cast["\0~\0attributes"] = $cast["\0~\0attributes"]->value;
-        $this->assertInstanceOf('Symfony\Component\VarDumper\Caster\ConstStub', $attr['CASE']);
+        $this->assertInstanceOf(\Symfony\Component\VarDumper\Caster\ConstStub::class, $attr['CASE']);
         $this->assertSame('NATURAL', $attr['CASE']->class);
         $this->assertSame('BOTH', $attr['DEFAULT_FETCH_MODE']->class);
 

Tests/Caster/ReflectionCasterTest.php

@@ -26,7 +26,7 @@ class ReflectionCasterTest extends TestCase
 
     public function testReflectionCaster()
     {
-        $var = new \ReflectionClass('ReflectionClass');
+        $var = new \ReflectionClass(\ReflectionClass::class);
 
         $this->assertDumpMatchesFormat(
             <<<'EOTXT'

Tests/Fixtures/dumb-var.php

@@ -2,7 +2,7 @@
 
 namespace Symfony\Component\VarDumper\Tests\Fixture;
 
-if (!class_exists('Symfony\Component\VarDumper\Tests\Fixture\DumbFoo')) {
+if (!class_exists(\Symfony\Component\VarDumper\Tests\Fixture\DumbFoo::class)) {
     class DumbFoo
     {
         public $foo = 'foo';