Include assertFileExists , assertFileNotExists and some others tests, I do not know if it was necessary, but ended up doing anyway.

Author: Roger Russel

tests/unit/Codeception/Module/AssertsTest.php

@@ -10,6 +10,16 @@ public function testAsserts()
         $module->assertNotSame(1,true);
         $module->assertRegExp('/^[\d]$/','1');
         $module->assertNotRegExp('/^[a-z]$/','1');
+        $module->assertEmpty([]);
+        $module->assertNotEmpty([1]);
+        $module->assertNull(null);
+        $module->assertNotNull('');
+        $module->assertNotNull(false);
+        $module->assertNotNull(0);
+        $module->assertTrue(true);
+        $module->assertFalse(false);
+        $module->assertFileExists(__FILE__);
+        $module->assertFileNotExists(__FILE__ . '.notExist');
     }
 
 }