Leaked Concurrency Handle (ARCH6085)

Key ruby.performance.leaked-concurrency-handle · Severity warning · Category performance

A lock acquired with lock and held without the block form is never released if an exception is raised, causing a deadlock. Manage the lock with the block form.

Incorrect

def increment(mutex, counter)
  mutex.lock
  counter.value += 1
  mutex.unlock
end

Correct

def increment(mutex, counter)
  mutex.synchronize do
    counter.value += 1
  end
end

Fix

Acquire locks with the synchronize block form; start threads with a bounded lifetime and join them.