import unittest

from migen import *


def _same_slices(a, b):
    return a.value is b.value and a.start == b.start and a.stop == b.stop


class SignalSizeCase(unittest.TestCase):
    def setUp(self):
        self.i = 0xaa
        self.j = -127
        self.s = Signal((13, True))

    def test_flen(self):
        self.assertEqual(flen(self.s), 13)
        self.assertEqual(flen(self.i), 8)
        self.assertEqual(flen(self.j), 8)

    def test_flen_type(self):
        self.assertRaises(TypeError, flen, [])

    def test_fiter(self):
        for i, si in enumerate(fiter(self.s)):
            self.assertTrue(_same_slices(si, self.s[i]))
        self.assertEqual(list(fiter(self.i)),
                [(self.i >> i) & 1 for i in range(8)])
        self.assertEqual(list(fiter(self.j)),
                [(self.j >> i) & 1 for i in range(8)])

    def test_fiter_type(self):
        self.assertRaises(TypeError, fiter, [])

    def test_fslice(self):
        sl = slice(1, None, 2)
        fslice(self.s, sl)
        self.assertEqual(fslice(self.i, sl), 15)
        self.assertEqual(fslice(self.j, sl), 8)
        self.assertEqual(fslice(-1, 9), 1)
        self.assertEqual(fslice(-1, slice(0, 4)), 0b1)
        self.assertEqual(fslice(-7, slice(0, None, 1)), 0b1001)

    def test_fslice_type(self):
        self.assertRaises(TypeError, fslice, [], 3)

    def test_freversed(self):
        freversed(self.s)
        freversed(self.i)
        freversed(self.j)

    def test_freveseed_type(self):
        self.assertRaises(TypeError, freversed, [])