# File lib/minitest/unit.rb, line 403
    def run_test_suites filter = /./
      @test_count, @assertion_count = 0, 0
      old_sync, @@out.sync = @@out.sync, true if @@out.respond_to? :sync=
      TestCase.test_suites.each do |suite|
        suite.test_methods.grep(filter).each do |test|
          inst = suite.new test
          inst._assertions = 0
          @@out.print "#{suite}##{test}: " if @verbose

          t = Time.now if @verbose
          result = inst.run(self)

          @@out.print "%.2f s: " % (Time.now - t) if @verbose
          @@out.print result
          @@out.puts if @verbose
          @test_count += 1
          @assertion_count += inst._assertions
        end
      end
      @@out.sync = old_sync if @@out.respond_to? :sync=
      [@test_count, @assertion_count]
    end