try {
      diff1.entriesInCommon().put(7, "x");
      fail();
    } catch (UnsupportedOperationException expected) {
    }
    try {
      diff1.entriesOnlyOnLeft().put(7, "x");
      fail();
    } catch (UnsupportedOperationException expected) {
    }
    try {
      diff1.entriesOnlyOnRight().put(7, "x");
      fail();
    } catch (UnsupportedOperationException expected) {
    }
  }

// copy returns a copy of the current state.
func (st *state) copy() *state {
	n := new(state)
	*n = *st
	return n
}

// fail panics with demangleErr, to be caught in doDemangle.
func (st *state) fail(err string) {
	panic(demangleErr{err: err, off: st.off})
}

// failEarlier is like fail, but decrements the offset to indicate
// that the point of failure occurred earlier in the string.

	}{{
		name:           "empty string should fail",
		path:           "",
		expectingError: true,
	}, {
		name:           "no slash should fail",
		path:           "foo",
		expectingError: true,
	}, {
		name:           "single slash should work",
		path:           "/",
		expectingError: false,
	}, {
		name:           "continuous slash should fail",
		path:           "//",
		expectingError: true,

    try {
      iterator.next();
      fail("no exception thrown");
    } catch (NoSuchElementException expected) {
    }
    try {
      iterator.previous();
      fail("no exception thrown");
    } catch (NoSuchElementException expected) {
    }
    try {
      iterator.remove();
      fail("no exception thrown");
    } catch (UnsupportedOperationException expected) {
    }

                    try {
                      peeker.getDone(input2Failed);
                      fail("Peeker.getDone() should fail for failed inputs");
                    } catch (ExecutionException expected) {
                    }
                    try {
                      peeker.getDone(nonInput);
                      fail("Peeker should not be able to peek into non-input ClosingFuture.");

                    try {
                      peeker.getDone(input2Failed);
                      fail("Peeker.getDone() should fail for failed inputs");
                    } catch (ExecutionException expected) {
                    }
                    try {
                      peeker.getDone(nonInput);
                      fail("Peeker should not be able to peek into non-input ClosingFuture.");

      fail();
    } catch (IllegalArgumentException expected) {
    }

    try {
      Set<Set<Integer>> unused = powerSet(ContiguousSet.closed(0, Integer.MAX_VALUE / 2));
      fail();
    } catch (IllegalArgumentException expected) {
    }

    try {
      powerSet(singleton(null));
      fail();
    } catch (NullPointerException expected) {
    }
  }

			var wg sync.WaitGroup
			wg.Add(1)
			go func(spec *volume.Spec, nodename string, fail bool) {
				defer wg.Done()
				attachID, err := csiAttacher.Attach(spec, types.NodeName(nodename))
				if !fail && err != nil {
					t.Errorf("expecting no failure, but got err: %v", err)
				}
				if fail && err == nil {
					t.Errorf("expecting failure, but got no err")
				}
				if attachID != "" {

		t.Errorf("expected: success-vol to be created")
	}

	// removing the path and simulating disk failure
	os.RemoveAll(path)
	// should fail with errDiskNotFound.
	if _, err = xlStorage.ListVols(context.Background()); err != errDiskNotFound {
		t.Errorf("Expected to fail with \"%s\", but instead failed with \"%s\"", errDiskNotFound, err)
	}
}

	FailOnSetupVolumeName = "fail-setup-volume"
	//TimeoutAndFailOnSetupVolumeName will first timeout and then fail the setup
	TimeoutAndFailOnSetupVolumeName = "timeout-and-fail-setup-volume"
	// SuccessAndTimeoutSetupVolumeName will cause first mount operation to succeed but subsequent attempts to timeout
	SuccessAndTimeoutSetupVolumeName = "success-and-timeout-setup-volume-name"