Method foreach

src/tests/containerizer/cgroups_tests.cpp:135–180

    CgroupsTest::SetUp();

    foreach (const string& subsystem, strings::tokenize(subsystems, ",")) {
      // Establish the base hierarchy if this is the first subsystem checked.
      if (baseHierarchy.empty()) {
        Result<string> hierarchy = cgroups::hierarchy(subsystem);
        ASSERT_FALSE(hierarchy.isError());

        if (hierarchy.isNone()) {
          baseHierarchy = TEST_CGROUPS_HIERARCHY;
        } else {
          // Strip the subsystem to get the base hierarchy.
          Try<string> baseDirname = Path(hierarchy.get()).dirname();
          ASSERT_SOME(baseDirname);
          baseHierarchy = baseDirname.get();
        }
      }

      // Mount the subsystem if necessary.
      string hierarchy = path::join(baseHierarchy, subsystem);
      Try<bool> mounted = cgroups::mounted(hierarchy, subsystem);
      ASSERT_SOME(mounted);
      if (!mounted.get()) {
        ASSERT_SOME(cgroups::mount(hierarchy, subsystem))
          << "-------------------------------------------------------------\n"
          << "We cannot run any cgroups tests that require\n"
          << "a hierarchy with subsystem '" << subsystem << "'\n"
          << "because we failed to find an existing hierarchy\n"
          << "or create a new one (tried '" << hierarchy << "').\n"
          << "You can either remove all existing\n"
          << "hierarchies, or disable this test case\n"
          << "(i.e., --gtest_filter=-"
          << ::testing::UnitTest::GetInstance()
              ->current_test_info()
              ->test_case_name() << ".*).\n"
          << "-------------------------------------------------------------";
      }

      Try<vector<string>> cgroups = cgroups::get(hierarchy);
      ASSERT_SOME(cgroups);

      foreach (const string& cgroup, cgroups.get()) {
        // Remove any cgroups that start with TEST_CGROUPS_ROOT.
        if (cgroup == TEST_CGROUPS_ROOT) {
          AWAIT_READY(cgroups::destroy(hierarchy, cgroup));
        }
      }
    }
  }

  void TearDown() override