"""
There was a deadlock problem when work count is smaller than number of threads.
"""

import numpy as np

from numba import float32, float64, int32, uint32
from numba.np.ufunc import Vectorize
import unittest


def vector_add(a, b):
    return a + b


class TestParallelLowWorkCount(unittest.TestCase):

    _numba_parallel_test_ = False

    def test_low_workcount(self):
        # build parallel native code ufunc
        pv = Vectorize(vector_add, target='parallel')
        for ty in (int32, uint32, float32, float64):
            pv.add(ty(ty, ty))
        para_ufunc = pv.build_ufunc()

        # build python ufunc
        np_ufunc = np.vectorize(vector_add)

        # test it out
        def test(ty):
            data = np.arange(1).astype(ty) # just one item
            result = para_ufunc(data, data)
            gold = np_ufunc(data, data)
            np.testing.assert_allclose(gold, result)

        test(np.double)
        test(np.float32)
        test(np.int32)
        test(np.uint32)


if __name__ == '__main__':
    unittest.main()