diff --git a/src/Assert.php b/src/Assert.php
index b8fa12ac..a0cd0154 100644
--- a/src/Assert.php
+++ b/src/Assert.php
@@ -37,14 +37,14 @@ class Assert
 
 	public function isNull($actual)
 	{
-		if ($actual !== null and $actual !== false)
-			$this->fail('Assertion failed. Expected: NULL, got: "' . $actual . '"');
+		if ($actual !== null)
+			$this->fail('Assertion failed. Expected: NULL, got: "' . $this->dumpVar(actual) . '"');
 	}
 
 	public function isNotNull($actual)
 	{
-		if ($actual === null or $actual === false)
-			$this->fail('Assertion failed. Expected: not NULL, got: "' . $actual . '"');
+		if ($actual === null)
+			$this->fail('Assertion failed. Expected: not NULL, got: "' . $this->dumpVar(actual) . '"');
 	}
 
 	public function isTrue($actual)
diff --git a/tests/Tests/JobTests/ActivateUserEmailJobTest.php b/tests/Tests/JobTests/ActivateUserEmailJobTest.php
index 126f512b..ed5cbf49 100644
--- a/tests/Tests/JobTests/ActivateUserEmailJobTest.php
+++ b/tests/Tests/JobTests/ActivateUserEmailJobTest.php
@@ -43,7 +43,7 @@ class ActivateUserEmailJobTest extends AbstractTest
 		UserModel::save($user);
 
 		$this->assert->areEqual('godzilla@whitestar.gov', $user->getUnconfirmedEmail());
-		$this->assert->areEqual(null, $user->getConfirmedEmail());
+		$this->assert->isNull($user->getConfirmedEmail());
 
 		$this->assert->doesNotThrow(function() use ($user)
 		{
@@ -68,7 +68,7 @@ class ActivateUserEmailJobTest extends AbstractTest
 		//reload local entity after changes done by the job
 		$user = UserModel::getById($user->getId());
 
-		$this->assert->areEqual(null, $user->getUnconfirmedEmail());
+		$this->assert->isNull($user->getUnconfirmedEmail());
 		$this->assert->areEqual('godzilla@whitestar.gov', $user->getConfirmedEmail());
 	}
 
@@ -82,7 +82,7 @@ class ActivateUserEmailJobTest extends AbstractTest
 		UserModel::save($user);
 
 		$this->assert->areEqual('godzilla@whitestar.gov', $user->getUnconfirmedEmail());
-		$this->assert->areEqual(null, $user->getConfirmedEmail());
+		$this->assert->isNull($user->getConfirmedEmail());
 
 		Api::run(
 			new ActivateUserEmailJob(),
diff --git a/tests/Tests/JobTests/AddPostJobTest.php b/tests/Tests/JobTests/AddPostJobTest.php
index 9da3b71d..5029111a 100644
--- a/tests/Tests/JobTests/AddPostJobTest.php
+++ b/tests/Tests/JobTests/AddPostJobTest.php
@@ -58,7 +58,7 @@ class AddPostJobTest extends AbstractTest
 			file_get_contents($post->getFullPath()),
 			file_get_contents($this->testSupport->getPath('image.jpg')));
 		$this->assert->areNotEqual(Auth::getCurrentUser()->getId(), $post->getUploaderId());
-		$this->assert->areEqual(null, $post->getUploaderId());
+		$this->assert->isNull($post->getUploaderId());
 	}
 
 	public function testPartialPrivilegeFail()
diff --git a/tests/Tests/JobTests/AddUserJobTest.php b/tests/Tests/JobTests/AddUserJobTest.php
index 8bbbac42..2ef0e7bc 100644
--- a/tests/Tests/JobTests/AddUserJobTest.php
+++ b/tests/Tests/JobTests/AddUserJobTest.php
@@ -162,7 +162,7 @@ class AddUserJobTest extends AbstractTest
 		});
 
 		//first user = admin = has confirmed e-mail automatically
-		$this->assert->areEqual(null, $user1->getUnconfirmedEmail());
+		$this->assert->isNull($user1->getUnconfirmedEmail());
 		$this->assert->areEqual('godzilla@whitestar.gov', $user1->getConfirmedEmail());
 
 		$user2 = $this->assert->doesNotThrow(function()
@@ -178,7 +178,7 @@ class AddUserJobTest extends AbstractTest
 
 		//any other user = non-admin = has to confirmed e-mail manually
 		$this->assert->areEqual('godzilla2@whitestar.gov', $user2->getUnconfirmedEmail());
-		$this->assert->areEqual(null, $user2->getConfirmedEmail());
+		$this->assert->isNull($user2->getConfirmedEmail());
 
 		$this->assert->areEqual(1, Mailer::getMailCounter());
 	}
@@ -204,7 +204,7 @@ class AddUserJobTest extends AbstractTest
 		});
 
 		$this->assert->areEqual('godzilla@whitestar.gov', $user1->getUnconfirmedEmail());
-		$this->assert->areEqual(null, $user1->getConfirmedEmail());
+		$this->assert->isNull($user1->getConfirmedEmail());
 
 		$user2 = $this->assert->doesNotThrow(function()
 		{
@@ -218,7 +218,7 @@ class AddUserJobTest extends AbstractTest
 		});
 
 		$this->assert->areEqual('godzilla2@whitestar.gov', $user2->getUnconfirmedEmail());
-		$this->assert->areEqual(null, $user2->getConfirmedEmail());
+		$this->assert->isNull($user2->getConfirmedEmail());
 
 		$this->assert->areEqual(2, Mailer::getMailCounter());
 	}
@@ -243,7 +243,7 @@ class AddUserJobTest extends AbstractTest
 				]);
 		});
 
-		$this->assert->areEqual(null, $user1->getUnconfirmedEmail());
+		$this->assert->isNull($user1->getUnconfirmedEmail());
 		$this->assert->areEqual('godzilla@whitestar.gov', $user1->getConfirmedEmail());
 
 		$user2 = $this->assert->doesNotThrow(function()
@@ -257,7 +257,7 @@ class AddUserJobTest extends AbstractTest
 				]);
 		});
 
-		$this->assert->areEqual(null, $user2->getUnconfirmedEmail());
+		$this->assert->isNull($user2->getUnconfirmedEmail());
 		$this->assert->areEqual('godzilla2@whitestar.gov', $user2->getConfirmedEmail());
 
 		$this->assert->areEqual(0, Mailer::getMailCounter());
diff --git a/tests/Tests/JobTests/DeletePostJobTest.php b/tests/Tests/JobTests/DeletePostJobTest.php
index 3e3f6cdf..a398b78e 100644
--- a/tests/Tests/JobTests/DeletePostJobTest.php
+++ b/tests/Tests/JobTests/DeletePostJobTest.php
@@ -16,7 +16,7 @@ class DeletePostJobTest extends AbstractTest
 				]);
 		});
 
-		$this->assert->areEqual(null, PostModel::tryGetByName($post->getName()));
+		$this->assert->isNull(PostModel::tryGetByName($post->getName()));
 		$this->assert->areEqual(0, PostModel::getCount());
 	}
 
diff --git a/tests/Tests/JobTests/DeleteUserJobTest.php b/tests/Tests/JobTests/DeleteUserJobTest.php
index 0a77011d..6611df7a 100644
--- a/tests/Tests/JobTests/DeleteUserJobTest.php
+++ b/tests/Tests/JobTests/DeleteUserJobTest.php
@@ -16,7 +16,7 @@ class DeleteUserJobTest extends AbstractTest
 				]);
 		});
 
-		$this->assert->areEqual(null, UserModel::tryGetByName($user->getName()));
+		$this->assert->isNull(UserModel::tryGetByName($user->getName()));
 		$this->assert->areEqual(0, UserModel::getCount());
 	}
 
diff --git a/tests/Tests/JobTests/EditUserEmailJobTest.php b/tests/Tests/JobTests/EditUserEmailJobTest.php
index d43869fa..41049dba 100644
--- a/tests/Tests/JobTests/EditUserEmailJobTest.php
+++ b/tests/Tests/JobTests/EditUserEmailJobTest.php
@@ -22,7 +22,7 @@ class EditUserEmailJobTest extends AbstractTest
 				]);
 		});
 
-		$this->assert->areEqual(null, $user->getUnconfirmedEmail());
+		$this->assert->isNull($user->getUnconfirmedEmail());
 		$this->assert->areEqual('xena@other-side.gr', $user->getConfirmedEmail());
 
 		$this->assert->areEqual(0, Mailer::getMailCounter());
@@ -50,7 +50,7 @@ class EditUserEmailJobTest extends AbstractTest
 		});
 
 		$this->assert->areEqual('xena@other-side.gr', $user->getUnconfirmedEmail());
-		$this->assert->areEqual(null, $user->getConfirmedEmail());
+		$this->assert->isNull($user->getConfirmedEmail());
 
 		$this->assert->areEqual(1, Mailer::getMailCounter());
 	}
@@ -100,8 +100,8 @@ class EditUserEmailJobTest extends AbstractTest
 				]);
 		}, 'User with this e-mail is already registered');
 
-		$this->assert->areEqual(null, $user->getUnconfirmedEmail());
-		$this->assert->areEqual(null, $user->getConfirmedEmail());
+		$this->assert->isNull($user->getUnconfirmedEmail());
+		$this->assert->isNull($user->getConfirmedEmail());
 
 		$this->assert->areEqual(0, Mailer::getMailCounter());
 	}
diff --git a/tests/Tests/JobTests/FeaturePostJobTest.php b/tests/Tests/JobTests/FeaturePostJobTest.php
index 894d80af..359a5332 100644
--- a/tests/Tests/JobTests/FeaturePostJobTest.php
+++ b/tests/Tests/JobTests/FeaturePostJobTest.php
@@ -41,6 +41,6 @@ class FeaturePostJobTest extends AbstractTest
 		});
 
 		$this->assert->areEqual($posts[1]->getId(), PropertyModel::get(PropertyModel::FeaturedPostId));
-		$this->assert->areEqual(null, PropertyModel::get(PropertyModel::FeaturedPostUserName));
+		$this->assert->isNull(PropertyModel::get(PropertyModel::FeaturedPostUserName));
 	}
 }
diff --git a/tests/Tests/MiscTests/TextHelperTest.php b/tests/Tests/MiscTests/TextHelperTest.php
index 6ae60612..492f0f34 100644
--- a/tests/Tests/MiscTests/TextHelperTest.php
+++ b/tests/Tests/MiscTests/TextHelperTest.php
@@ -25,12 +25,12 @@ class TextHelperTest extends AbstractTest
 		$this->assert->areEqual(-2, TextHelper::toIntegerOrNull('-2'));
 		$this->assert->areEqual(0, TextHelper::toIntegerOrNull(0));
 		$this->assert->areEqual(0, TextHelper::toIntegerOrNull('0'));
-		$this->assert->areEqual(null, TextHelper::toIntegerOrNull('rubbish'));
-		$this->assert->areEqual(null, TextHelper::toIntegerOrNull('1e1'));
-		$this->assert->areEqual(null, TextHelper::toIntegerOrNull('1.7'));
-		$this->assert->areEqual(null, TextHelper::toIntegerOrNull(true));
-		$this->assert->areEqual(null, TextHelper::toIntegerOrNull(false));
-		$this->assert->areEqual(null, TextHelper::toIntegerOrNull(null));
+		$this->assert->isNull(TextHelper::toIntegerOrNull('rubbish'));
+		$this->assert->isNull(TextHelper::toIntegerOrNull('1e1'));
+		$this->assert->isNull(TextHelper::toIntegerOrNull('1.7'));
+		$this->assert->isNull(TextHelper::toIntegerOrNull(true));
+		$this->assert->isNull(TextHelper::toIntegerOrNull(false));
+		$this->assert->isNull(TextHelper::toIntegerOrNull(null));
 	}
 
 	public function testToBooleanOrNull()
@@ -51,9 +51,9 @@ class TextHelperTest extends AbstractTest
 		$this->assert->isFalse(TextHelper::toBooleanOrNull('FaLsE'));
 		$this->assert->isFalse(TextHelper::toBooleanOrNull('false'));
 		$this->assert->isFalse(TextHelper::toBooleanOrNull(false));
-		$this->assert->areEqual(null, TextHelper::toBooleanOrNull(2));
-		$this->assert->areEqual(null, TextHelper::toBooleanOrNull('2'));
-		$this->assert->areEqual(null, TextHelper::toBooleanOrNull('rubbish'));
-		$this->assert->areEqual(null, TextHelper::toBooleanOrNull(null));
+		$this->assert->isNull(TextHelper::toBooleanOrNull(2));
+		$this->assert->isNull(TextHelper::toBooleanOrNull('2'));
+		$this->assert->isNull(TextHelper::toBooleanOrNull('rubbish'));
+		$this->assert->isNull(TextHelper::toBooleanOrNull(null));
 	}
 }
diff --git a/tests/Tests/ModelTests/PostModelTest.php b/tests/Tests/ModelTests/PostModelTest.php
index 60d97d91..08cef62b 100644
--- a/tests/Tests/ModelTests/PostModelTest.php
+++ b/tests/Tests/ModelTests/PostModelTest.php
@@ -8,7 +8,7 @@ class PostModelTest extends AbstractTest
 			return PostModel::getFeaturedPost();
 		});
 
-		$this->assert->areEqual(null, $post);
+		$this->assert->isNull($post);
 	}
 
 	public function testFeaturingNoPost()
@@ -20,7 +20,7 @@ class PostModelTest extends AbstractTest
 			return PostModel::getFeaturedPost();
 		});
 
-		$this->assert->areEqual(null, $post);
+		$this->assert->isNull($post);
 	}
 
 	public function testFeaturingRandomPost()
@@ -46,7 +46,7 @@ class PostModelTest extends AbstractTest
 
 		PostModel::featureRandomPost();
 
-		$this->assert->areEqual(null, PropertyModel::get(PropertyModel::FeaturedPostId));
+		$this->assert->isNull(PropertyModel::get(PropertyModel::FeaturedPostId));
 	}
 
 	public function testAutoFeaturingFirstTime()