rspec/rules/S5999/rule.adoc

When constructing an ``++std::scoped_lock++``, the constructor arguments are used to list the mutexes that the ``++scoped_lock++`` will lock on the creation and unlock on destruction. It is possible to construct a ``++scoped_lock++`` without any parameter, but in that case, it does absolutely nothing and is just dead code, which was probably not the intent of the user.


== Noncompliant Code Example

----
void f1(std::mutex &m) {
  std::scoped_lock lock; // Noncompliant
  // Do some work
}
----


== Compliant Solution

----
void f1(std::mutex &m) {
  std::scoped_lock lock {m}; // Compliant
  // Do some work
}

template<class... D>
void processAll(D &...data) {
  scoped_lock lock {data.getMutex()...}; // Compliant, even if the list might be empty in some cases
  // Do some work
}
----