def test_get_indexer(self):
# GH 17717
p1 = Period("2017-09-01")
p2 = Period("2017-09-04")
p3 = Period("2017-09-07")
tp0 = Period("2017-08-31")
tp1 = Period("2017-09-02")
tp2 = Period("2017-09-05")
tp3 = Period("2017-09-09")
idx = PeriodIndex([p1, p2, p3])
tm.assert_numpy_array_equal(idx.get_indexer(idx),
np.array([0, 1, 2], dtype=np.intp))
target = PeriodIndex([tp0, tp1, tp2, tp3])
tm.assert_numpy_array_equal(idx.get_indexer(target, "pad"),
np.array([-1, 0, 1, 2], dtype=np.intp))
tm.assert_numpy_array_equal(idx.get_indexer(target, "backfill"),
np.array([0, 1, 2, -1], dtype=np.intp))
tm.assert_numpy_array_equal(idx.get_indexer(target, "nearest"),
np.array([0, 0, 1, 2], dtype=np.intp))
res = idx.get_indexer(target, "nearest", tolerance=Timedelta("1 day"))
tm.assert_numpy_array_equal(res, np.array([0, 0, 1, -1],
dtype=np.intp))
