public function testErrnoToString()
 {
     $this->assertEquals("E_ERROR", Logger::errnoToString(E_ERROR));
     $this->assertEquals("E_WARNING", Logger::errnoToString(E_WARNING));
     $this->assertEquals("E_PARSE", Logger::errnoToString(E_PARSE));
     $this->assertEquals("E_NOTICE", Logger::errnoToString(E_NOTICE));
     $this->assertEquals("E_CORE_ERROR", Logger::errnoToString(E_CORE_ERROR));
     $this->assertEquals("E_CORE_WARNING", Logger::errnoToString(E_CORE_WARNING));
     $this->assertEquals("E_COMPILE_ERROR", Logger::errnoToString(E_COMPILE_ERROR));
     $this->assertEquals("E_COMPILE_WARNING", Logger::errnoToString(E_COMPILE_WARNING));
     $this->assertEquals("E_USER_ERROR", Logger::errnoToString(E_USER_ERROR));
     $this->assertEquals("E_USER_WARNING", Logger::errnoToString(E_USER_WARNING));
     $this->assertEquals("E_USER_NOTICE", Logger::errnoToString(E_USER_NOTICE));
     $this->assertEquals("E_STRICT", Logger::errnoToString(E_STRICT));
     $this->assertEquals("E_RECOVERABLE_ERROR", Logger::errnoToString(E_RECOVERABLE_ERROR));
     $this->assertEquals("E_DEPRECATED", Logger::errnoToString(E_DEPRECATED));
     $this->assertEquals("E_USER_DEPRECATED", Logger::errnoToString(E_USER_DEPRECATED));
     $this->assertEquals("", Logger::errnoToString(-1));
 }