diff --git a/tests/lib/SimpleSAML/Auth/SimpleTest.php b/tests/lib/SimpleSAML/Auth/SimpleTest.php
index 7e5799634165577e75e7d482ffd1311fe9503aa6..b78f24b446f04c1b63503d6d74f6abbb188f3ab5 100644
--- a/tests/lib/SimpleSAML/Auth/SimpleTest.php
+++ b/tests/lib/SimpleSAML/Auth/SimpleTest.php
@@ -2,6 +2,8 @@
 
 namespace SimpleSAML\Test\Auth;
 
+use SimpleSAML\Auth;
+
 /**
  * Tests for \SimpleSAML\Auth\Simple
  *
@@ -14,7 +16,7 @@ class SimpleTest extends \SimpleSAML\Test\Utils\ClearStateTestCase
      */
     public function testGetProcessedURL()
     {
-        $class = new \ReflectionClass('\SimpleSAML\Auth\Simple');
+        $class = new \ReflectionClass(Auth\Simple::class);
         $method = $class->getMethod('getProcessedURL');
         $method->setAccessible(true);
 
diff --git a/tests/lib/SimpleSAML/Auth/SourceTest.php b/tests/lib/SimpleSAML/Auth/SourceTest.php
index 26c382c54dc4ae799f8a26f275fab5c159726a9d..fe326f5d0666fe0093570b55ab3f4ed1f4729237 100644
--- a/tests/lib/SimpleSAML/Auth/SourceTest.php
+++ b/tests/lib/SimpleSAML/Auth/SourceTest.php
@@ -16,16 +16,16 @@ class SourceTest extends ClearStateTestCase
      */
     public function testParseAuthSource()
     {
-        $class = new \ReflectionClass('\SimpleSAML\Auth\Source');
+        $class = new \ReflectionClass(\SimpleSAML\Auth\Source::class);
         $method = $class->getMethod('parseAuthSource');
         $method->setAccessible(true);
 
         // test direct instantiation of the auth source object
-        $authSource = $method->invokeArgs(null, ['test', ['SimpleSAML\Test\Utils\TestAuthSource']]);
-        $this->assertInstanceOf('SimpleSAML\Test\Utils\TestAuthSource', $authSource);
+        $authSource = $method->invokeArgs(null, ['test', [TestAuthSource::class]]);
+        $this->assertInstanceOf(TestAuthSource::class, $authSource);
 
         // test instantiation via an auth source factory
-        $authSource = $method->invokeArgs(null, ['test', ['SimpleSAML\Test\Utils\TestAuthSourceFactory']]);
-        $this->assertInstanceOf('SimpleSAML\Test\Utils\TestAuthSource', $authSource);
+        $authSource = $method->invokeArgs(null, ['test', [TestAuthSourceFactory::class]]);
+        $this->assertInstanceOf(TestAuthSource::class, $authSource);
     }
 }
diff --git a/tests/lib/SimpleSAML/ConfigurationTest.php b/tests/lib/SimpleSAML/ConfigurationTest.php
index fcc463003573bc37dde1b02a24029c10fb2d5e0c..9c15f78b3f922eb3226e6d27f5344e8845162bd1 100644
--- a/tests/lib/SimpleSAML/ConfigurationTest.php
+++ b/tests/lib/SimpleSAML/ConfigurationTest.php
@@ -526,8 +526,8 @@ class ConfigurationTest extends \SimpleSAML\Test\Utils\ClearStateTestCase
         $this->assertNull($c->getConfigItem('missing_opt', null));
         $opt = $c->getConfigItem('opt');
         $notOpt = $c->getConfigItem('notOpt');
-        $this->assertInstanceOf('SimpleSAML\Configuration', $opt);
-        $this->assertInstanceOf('SimpleSAML\Configuration', $notOpt);
+        $this->assertInstanceOf(Configuration::class, $opt);
+        $this->assertInstanceOf(Configuration::class, $notOpt);
         $this->assertEquals($opt->getValue('a'), 42);
     }
 
@@ -562,9 +562,9 @@ class ConfigurationTest extends \SimpleSAML\Test\Utils\ClearStateTestCase
         $opts = $c->getConfigList('opts');
         $this->assertInternalType('array', $opts);
         $this->assertEquals(array_keys($opts), ['a', 'b']);
-        $this->assertInstanceOf('SimpleSAML\Configuration', $opts['a']);
+        $this->assertInstanceOf(Configuration::class, $opts['a']);
         $this->assertEquals($opts['a']->getValue('opt1'), 'value1');
-        $this->assertInstanceOf('SimpleSAML\Configuration', $opts['b']);
+        $this->assertInstanceOf(Configuration::class, $opts['b']);
         $this->assertEquals($opts['b']->getValue('opt2'), 'value2');
     }
 
diff --git a/tests/lib/SimpleSAML/DatabaseTest.php b/tests/lib/SimpleSAML/DatabaseTest.php
index 0e98f91577166ad8462e153c8caa7a0dbff1d51f..18cac06cc12116b68a27b290ec7d0a247404b4eb 100644
--- a/tests/lib/SimpleSAML/DatabaseTest.php
+++ b/tests/lib/SimpleSAML/DatabaseTest.php
@@ -3,6 +3,8 @@
 namespace SimpleSAML\Test;
 
 use PHPUnit\Framework\TestCase;
+use SimpleSAML\Configuration;
+use SimpleSAML\Database;
 
 /**
  * This test ensures that the \SimpleSAML\Database class can properly
@@ -37,7 +39,7 @@ class DatabaseTest extends TestCase
      */
     protected static function getMethod($getMethod)
     {
-        $class = new \ReflectionClass('SimpleSAML\Database');
+        $class = new \ReflectionClass(Database::class);
         $method = $class->getMethod($getMethod);
         $method->setAccessible(true);
         return $method;
@@ -62,16 +64,16 @@ class DatabaseTest extends TestCase
             'database.slaves'     => [],
         ];
 
-        $this->config = new \SimpleSAML\Configuration($config, "test/SimpleSAML/DatabaseTest.php");
+        $this->config = new Configuration($config, "test/SimpleSAML/DatabaseTest.php");
 
         // Ensure that we have a functional configuration class
-        $this->assertInstanceOf('SimpleSAML\Configuration', $this->config);
+        $this->assertInstanceOf(Configuration::class, $this->config);
         $this->assertEquals($config['database.dsn'], $this->config->getString('database.dsn'));
 
-        $this->db = \SimpleSAML\Database::getInstance($this->config);
+        $this->db = Database::getInstance($this->config);
 
         // Ensure that we have a functional database class.
-        $this->assertInstanceOf('SimpleSAML\Database', $this->db);
+        $this->assertInstanceOf(Database::class, $this->db);
     }
 
 
@@ -95,8 +97,8 @@ class DatabaseTest extends TestCase
             'database.slaves'     => [],
         ];
 
-        $this->config = new \SimpleSAML\Configuration($config, "test/SimpleSAML/DatabaseTest.php");
-        \SimpleSAML\Database::getInstance($this->config);
+        $this->config = new Configuration($config, "test/SimpleSAML/DatabaseTest.php");
+        Database::getInstance($this->config);
     }
 
 
@@ -127,13 +129,13 @@ class DatabaseTest extends TestCase
             'database.slaves'     => [],
         ];
 
-        $config1 = new \SimpleSAML\Configuration($config, "test/SimpleSAML/DatabaseTest.php");
-        $config2 = new \SimpleSAML\Configuration($config2, "test/SimpleSAML/DatabaseTest.php");
-        $config3 = new \SimpleSAML\Configuration($config, "test/SimpleSAML/DatabaseTest.php");
+        $config1 = new Configuration($config, "test/SimpleSAML/DatabaseTest.php");
+        $config2 = new Configuration($config2, "test/SimpleSAML/DatabaseTest.php");
+        $config3 = new Configuration($config, "test/SimpleSAML/DatabaseTest.php");
 
-        $db1 = \SimpleSAML\Database::getInstance($config1);
-        $db2 = \SimpleSAML\Database::getInstance($config2);
-        $db3 = \SimpleSAML\Database::getInstance($config3);
+        $db1 = Database::getInstance($config1);
+        $db2 = Database::getInstance($config2);
+        $db3 = Database::getInstance($config3);
 
         $generateInstanceId = self::getMethod('generateInstanceId');
 
@@ -202,8 +204,8 @@ class DatabaseTest extends TestCase
             ],
         ];
 
-        $sspConfiguration = new \SimpleSAML\Configuration($config, "test/SimpleSAML/DatabaseTest.php");
-        $msdb = \SimpleSAML\Database::getInstance($sspConfiguration);
+        $sspConfiguration = new Configuration($config, "test/SimpleSAML/DatabaseTest.php");
+        $msdb = Database::getInstance($sspConfiguration);
 
         $slaves = \PHPUnit\Framework\Assert::readAttribute($msdb, 'dbSlaves');
         $gotSlave = spl_object_hash($getSlave->invokeArgs($msdb, []));
diff --git a/tests/lib/SimpleSAML/SessionHandlerPHPTest.php b/tests/lib/SimpleSAML/SessionHandlerPHPTest.php
index 1ae63c4449e239946220e45182e5e296a3a299e8..279fe0725bef72468bfc386ab263bcd6f6c4630d 100644
--- a/tests/lib/SimpleSAML/SessionHandlerPHPTest.php
+++ b/tests/lib/SimpleSAML/SessionHandlerPHPTest.php
@@ -56,7 +56,7 @@ class SessionHandlerPHPTest extends ClearStateTestCase
     {
         Configuration::loadFromArray($this->sessionConfig, '[ARRAY]', 'simplesaml');
         $sh = SessionHandlerPHP::getSessionHandler();
-        $this->assertInstanceOf('\SimpleSAML\SessionHandlerPHP', $sh);
+        $this->assertInstanceOf(SessionHandlerPHP::class, $sh);
     }
 
 
diff --git a/tests/lib/SimpleSAML/Store/RedisTest.php b/tests/lib/SimpleSAML/Store/RedisTest.php
index 3f5593360bed8f0fbc4f16c740a2205456352067..690ad36da7cd66ea239daa3a8c7812a53a2b679b 100644
--- a/tests/lib/SimpleSAML/Store/RedisTest.php
+++ b/tests/lib/SimpleSAML/Store/RedisTest.php
@@ -3,6 +3,7 @@
 namespace SimpleSAML\Test\Store;
 
 use PHPUnit\Framework\TestCase;
+use Predis\Client;
 use SimpleSAML\Configuration;
 use SimpleSAML\Store;
 
@@ -33,7 +34,7 @@ class RedisTest extends TestCase
     {
         $this->config = [];
 
-        $this->mocked_redis = $this->getMockBuilder('Predis\Client')
+        $this->mocked_redis = $this->getMockBuilder(Client::class)
                                    ->setMethods(['get', 'set', 'setex', 'del', 'disconnect'])
                                    ->disableOriginalConstructor()
                                    ->getMock();
@@ -127,10 +128,10 @@ class RedisTest extends TestCase
         /** @var \SimpleSAML\Store\Redis $store */
         $store = Store::getInstance();
 
-        $this->assertInstanceOf('SimpleSAML\Store\Redis', $store);
+        $this->assertInstanceOf(Store\Redis::class, $store);
 
-        $this->clearInstance($config, '\SimpleSAML\Configuration');
-        $this->clearInstance($store, '\SimpleSAML\Store');
+        $this->clearInstance($config, Configuration::Class);
+        $this->clearInstance($store, Store::class);
     }
 
 
@@ -151,10 +152,10 @@ class RedisTest extends TestCase
         /** @var \SimpleSAML\Store\Redis $store */
         $store = Store::getInstance();
 
-        $this->assertInstanceOf('SimpleSAML\Store\Redis', $store);
+        $this->assertInstanceOf(Store\Redis::class, $store);
 
-        $this->clearInstance($config, '\SimpleSAML\Configuration');
-        $this->clearInstance($store, '\SimpleSAML\Store');
+        $this->clearInstance($config, Configuration::class);
+        $this->clearInstance($store, Store::class);
     }
 
 
diff --git a/tests/lib/SimpleSAML/StoreTest.php b/tests/lib/SimpleSAML/StoreTest.php
index 8b95bede1b5df91ea9b11e914f24f34ff5051aae..65d429d362a2c1c5318b0455c3f14a4e7ddfd8c9 100644
--- a/tests/lib/SimpleSAML/StoreTest.php
+++ b/tests/lib/SimpleSAML/StoreTest.php
@@ -63,7 +63,7 @@ class StoreTest extends TestCase
 
         $store = Store::getInstance();
 
-        $this->assertInstanceOf('\SimpleSAML\Store\Memcache', $store);
+        $this->assertInstanceOf(Store\Memcache::class, $store);
     }
 
 
@@ -82,7 +82,7 @@ class StoreTest extends TestCase
 
         $store = Store::getInstance();
 
-        $this->assertInstanceOf('SimpleSAML\Store\SQL', $store);
+        $this->assertInstanceOf(Store\SQL::class, $store);
     }
 
 
@@ -101,7 +101,7 @@ class StoreTest extends TestCase
 
         $store = Store::getInstance();
 
-        $this->assertInstanceOf('SimpleSAML\Store\SQL', $store);
+        $this->assertInstanceOf(Store\SQL::class, $store);
     }
 
 
@@ -132,8 +132,8 @@ class StoreTest extends TestCase
         /** @var \SimpleSAML\Store $store */
         $store = Store::getInstance();
 
-        $this->clearInstance($config, '\SimpleSAML\Configuration');
-        $this->clearInstance($store, '\SimpleSAML\Store');
+        $this->clearInstance($config, Configuration::class);
+        $this->clearInstance($store, Store::class);
     }
 
 
diff --git a/tests/modules/core/lib/Auth/Process/CardinalitySingleTest.php b/tests/modules/core/lib/Auth/Process/CardinalitySingleTest.php
index 53cc8a104894c412887e4c0d2583b92910a0b3ba..9c01dbeb008d05de76e603ed836f00f1028d40ea 100644
--- a/tests/modules/core/lib/Auth/Process/CardinalitySingleTest.php
+++ b/tests/modules/core/lib/Auth/Process/CardinalitySingleTest.php
@@ -2,6 +2,8 @@
 
 namespace SimpleSAML\Test\Module\core\Auth\Process;
 
+use SimpleSAML\Utils\HTTPAdapter;
+
 /**
  * Test for the core:CardinalitySingle filter.
  */
@@ -38,7 +40,7 @@ class CardinalitySingleTest extends \PHPUnit\Framework\TestCase
     protected function setUp()
     {
         \SimpleSAML\Configuration::loadFromArray([], '[ARRAY]', 'simplesaml');
-        $this->http = $this->getMockBuilder('SimpleSAML\Utils\HTTPAdapter')
+        $this->http = $this->getMockBuilder(HTTPAdapter::class)
                            ->setMethods(['redirectTrustedURL'])
                            ->getMock();
     }
diff --git a/tests/modules/core/lib/Auth/Process/CardinalityTest.php b/tests/modules/core/lib/Auth/Process/CardinalityTest.php
index 3b666c25e31ce7deb784094eec2ab502128c01d2..edccfbab0a19f3a25216f4826f6beef56f82a336 100644
--- a/tests/modules/core/lib/Auth/Process/CardinalityTest.php
+++ b/tests/modules/core/lib/Auth/Process/CardinalityTest.php
@@ -2,6 +2,9 @@
 
 namespace SimpleSAML\Test\Module\core\Auth\Process;
 
+use SimpleSAML\Error\Exception as SspException;
+use SimpleSAML\Utils\HTTPAdapter;
+
 /**
  * Test for the core:Cardinality filter.
  */
@@ -38,7 +41,7 @@ class CardinalityTest extends \PHPUnit\Framework\TestCase
     protected function setUp()
     {
         \SimpleSAML\Configuration::loadFromArray([], '[ARRAY]', 'simplesaml');
-        $this->http = $this->getMockBuilder('SimpleSAML\Utils\HTTPAdapter')
+        $this->http = $this->getMockBuilder(HTTPAdapter::class)
                            ->setMethods(['redirectTrustedURL'])
                            ->getMock();
     }
@@ -185,7 +188,7 @@ class CardinalityTest extends \PHPUnit\Framework\TestCase
      */
     public function testMinInvalid()
     {
-        $this->expectException(\SimpleSAML\Error\Exception::class);
+        $this->expectException(SspException::class);
         $this->expectExceptionMessageRegExp('/Minimum/');
         $config = [
             'mail' => ['min' => false],
@@ -205,7 +208,7 @@ class CardinalityTest extends \PHPUnit\Framework\TestCase
      */
     public function testMinNegative()
     {
-        $this->expectException(\SimpleSAML\Error\Exception::class);
+        $this->expectException(SspException::class);
         $this->expectExceptionMessageRegExp('/Minimum/');
         $config = [
             'mail' => ['min' => -1],
@@ -225,7 +228,7 @@ class CardinalityTest extends \PHPUnit\Framework\TestCase
      */
     public function testMaxInvalid()
     {
-        $this->expectException(\SimpleSAML\Error\Exception::class);
+        $this->expectException(SspException::class);
         $this->expectExceptionMessageRegExp('/Maximum/');
         $config = [
             'mail' => ['max' => false],
@@ -245,7 +248,7 @@ class CardinalityTest extends \PHPUnit\Framework\TestCase
      */
     public function testMinGreaterThanMax()
     {
-        $this->expectException(\SimpleSAML\Error\Exception::class);
+        $this->expectException(SspException::class);
         $this->expectExceptionMessageRegExp('/less than/');
         $config = [
             'mail' => ['min' => 2, 'max' => 1],
@@ -265,7 +268,7 @@ class CardinalityTest extends \PHPUnit\Framework\TestCase
      */
     public function testInvalidAttributeName()
     {
-        $this->expectException(\SimpleSAML\Error\Exception::class);
+        $this->expectException(SspException::class);
         $this->expectExceptionMessageRegExp('/Invalid attribute/');
         $config = [
             ['min' => 2, 'max' => 1],
diff --git a/tests/modules/core/lib/Auth/UserPassBaseTest.php b/tests/modules/core/lib/Auth/UserPassBaseTest.php
index 089f3c345217f9a0d8652e966e14fd4d19299113..bb897b9eaddf27bb855b0e774a31aa69ca7dfef9 100644
--- a/tests/modules/core/lib/Auth/UserPassBaseTest.php
+++ b/tests/modules/core/lib/Auth/UserPassBaseTest.php
@@ -2,6 +2,10 @@
 
 namespace SimpleSAML\Test\Module\core\Auth;
 
+use SAML2\Constants;
+use SimpleSAML\Error\Error as SspError;
+use SimpleSAML\Module\core\Auth\UserPassBase;
+
 class UserPassBaseTest extends \PHPUnit\Framework\TestCase
 {
     /**
@@ -10,7 +14,7 @@ class UserPassBaseTest extends \PHPUnit\Framework\TestCase
     public function testAuthenticateECPCallsLoginAndSetsAttributes()
     {
         $state = [
-            'saml:Binding' => \SAML2\Constants::BINDING_PAOS,
+            'saml:Binding' => Constants::BINDING_PAOS,
         ];
         $attributes = ['attrib' => 'val'];
 
@@ -18,7 +22,7 @@ class UserPassBaseTest extends \PHPUnit\Framework\TestCase
         $password = $_SERVER['PHP_AUTH_PW'] = 'password';
 
         /** @var \SimpleSAML\Module\core\Auth\UserPassBase $stub */
-        $stub = $this->getMockBuilder('\SimpleSAML\Module\core\Auth\UserPassBase')
+        $stub = $this->getMockBuilder(UserPassBase::class)
             ->disableOriginalConstructor()
             ->setMethods(['login'])
             ->getMockForAbstractClass();
@@ -43,18 +47,18 @@ class UserPassBaseTest extends \PHPUnit\Framework\TestCase
      */
     public function testAuthenticateECPMissingUsername()
     {
-        $this->expectException(\SimpleSAML\Error\Error::class);
+        $this->expectException(SspError::class);
         $this->expectExceptionMessage('WRONGUSERPASS');
 
         $state = [
-            'saml:Binding' => \SAML2\Constants::BINDING_PAOS,
+            'saml:Binding' => Constants::BINDING_PAOS,
         ];
 
         unset($_SERVER['PHP_AUTH_USER']);
         $_SERVER['PHP_AUTH_PW'] = 'password';
 
         /** @var \SimpleSAML\Module\core\Auth\UserPassBase $stub */
-        $stub = $this->getMockBuilder('\SimpleSAML\Module\core\Auth\UserPassBase')
+        $stub = $this->getMockBuilder(UserPassBase::class)
             ->disableOriginalConstructor()
             ->getMockForAbstractClass();
 
@@ -67,17 +71,17 @@ class UserPassBaseTest extends \PHPUnit\Framework\TestCase
      */
     public function testAuthenticateECPMissingPassword()
     {
-        $this->expectException(\SimpleSAML\Error\Error::class);
+        $this->expectException(SspError::class);
         $this->expectExceptionMessage('WRONGUSERPASS');
 
         $state = [
-            'saml:Binding' => \SAML2\Constants::BINDING_PAOS,
+            'saml:Binding' => Constants::BINDING_PAOS,
         ];
 
         $_SERVER['PHP_AUTH_USER'] = 'username';
         unset($_SERVER['PHP_AUTH_PW']);
 
-        $stub = $this->getMockBuilder('\SimpleSAML\Module\core\Auth\UserPassBase')
+        $stub = $this->getMockBuilder(UserPassBase::class)
             ->disableOriginalConstructor()
             ->getMockForAbstractClass();
 
@@ -92,7 +96,7 @@ class UserPassBaseTest extends \PHPUnit\Framework\TestCase
     public function testAuthenticateECPCallsLoginWithForcedUsername()
     {
         $state = [
-            'saml:Binding' => \SAML2\Constants::BINDING_PAOS,
+            'saml:Binding' => Constants::BINDING_PAOS,
         ];
         $attributes = [];
 
@@ -102,7 +106,7 @@ class UserPassBaseTest extends \PHPUnit\Framework\TestCase
         $password = $_SERVER['PHP_AUTH_PW'] = 'password';
 
         /** @var \SimpleSAML\Module\core\Auth\UserPassBase $stub */
-        $stub = $this->getMockBuilder('\SimpleSAML\Module\core\Auth\UserPassBase')
+        $stub = $this->getMockBuilder(UserPassBase::class)
             ->disableOriginalConstructor()
             ->setMethods(['login'])
             ->getMockForAbstractClass();