/**
  * Update/add a spec for a given specsPerClass object.
  * It returns a new instance.
  *
  * @param \Box\TestScribe\Spec\SpecsPerClass $specsPerClass
  * @param string $methodName
  * @param OneSpec $oneSpec
  *
  * @return \Box\TestScribe\Spec\SpecsPerClass
  */
 public function addOneSpec(SpecsPerClass $specsPerClass, $methodName, OneSpec $oneSpec)
 {
     $specsPerMethod = $specsPerClass->getSpecsPerMethodByName($methodName);
     $newSpecsPerMethod = $this->specsPerMethodService->addOneSpec($specsPerMethod, $oneSpec);
     $specs = $specsPerClass->getSpecs();
     $fullClassName = $specsPerClass->getFullClassName();
     $specs[$methodName] = $newSpecsPerMethod;
     $newSpecsPerClass = new SpecsPerClass($fullClassName, $specs);
     return $newSpecsPerClass;
 }