lib/threads.rb in threads-0.2.0 vs lib/threads.rb in threads-0.3.0

@@ -21,18 +21,23 @@
 # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
 require 'concurrent'
+require 'backtrace'
 
 # Threads.
 # Author:: Yegor Bugayenko ([e-mail])
 # Copyright:: Copyright (c) 2018 Yegor Bugayenko
 # License:: MIT
 class Threads
-  def initialize(total = Concurrent.processor_count * 8)
+  def initialize(total = Concurrent.processor_count * 8, log: STDOUT)
+    raise "Total can't be nil" if total.nil?
+    raise "Total can't be negative or zero: #{total}" unless total.positive?
     @total = total
+    raise "Log can't be nil" if log.nil?
+    @log = log
   end
 
   def assert(reps = @total)
     if reps < @total
       raise "Repetition counter #{reps} can't be smaller than #{@total}"
@@ -49,11 +54,11 @@
           r = rep.increment
           break if r > reps
           begin
             yield(t, r - 1)
           rescue StandardError => e
-            puts Backtrace.new(e)
+            print(Backtrace.new(e))
             raise e
           end
         end
         done.increment
       end
@@ -61,7 +66,17 @@
     latch.count_down
     pool.shutdown
     raise "Can't stop the pool" unless pool.wait_for_termination(30)
     return if done.value == @total
     raise "Only #{done.value} out of #{@total} threads completed successfully"
+  end
+
+  private
+
+  def print(msg)
+    if @log.respond_to?(:error)
+      @log.error(msg)
+    elsif @log.respond_to?(:puts)
+      @log.puts(msg)
+    end
   end
 end