def test_case_two(self):
x = 0b111000111
middleish_bits = BitField(6, 7)
all_bits = BitField(0, 9)
self.assertEqual(middleish_bits.extract(x), 3)
self.assertEqual(
all_bits.extract(x),
0b111000111) # check to see if x is altered from extraction
def test_case_one(self):
x = 0b111000111
bitfield_low = BitField(0, 3)
bitfield_mid = BitField(4, 5)
bitfield_low.insert(x, 1)
self.assertEqual(bitfield_low.extract(x), 0b111) # 7
self.assertEqual(bitfield_mid.extract(x),
0) # middle should still == 0 after insertion
def test_invert(self):
lowpart = BitField(0, 3)
midpart = BitField(4, 6)
highpart = BitField(7, 9)
for v in range(8):
packed = 0
packed = lowpart.insert(v, packed)
packed = midpart.insert(v, packed)
packed = highpart.insert(v, packed)
self.assertEqual(lowpart.extract(packed), v)
self.assertEqual(midpart.extract(packed), v)
self.assertEqual(highpart.extract(packed), v)
def test_low_order(self):
low_4 = BitField(0, 3)
# A value that fits snugly in the first 4 bits
self.assertEqual(low_4.insert(13, 0), 13)
# A value that doesn't fit; some high bits lost
self.assertEqual(low_4.insert(21, 0), 5)
# Extract unsigned
self.assertEqual(low_4.extract(15), 15)
# Or convert negative numbers
self.assertEqual(low_4.extract_signed(15), -1)
# Doesn't clobber other bits
higher = 15 << 4
self.assertEqual(low_4.insert(13, higher), 13 + higher)
# Extraction is masked
packed = low_4.insert(13, higher)
self.assertEqual(low_4.extract(packed), 13)
def test_middle_bits(self):
mid_4 = BitField(4, 7)
# A value that fits snugly in4 bits
self.assertEqual(mid_4.insert(13, 0), 13 << 4)
# A value that doesn't fit; some high bits lost
self.assertEqual(mid_4.insert(21, 0), 5 << 4)
# Extract unsigned
self.assertEqual(mid_4.extract(15 << 4), 15)
# Or convert negative numbers
self.assertEqual(mid_4.extract_signed(15 << 4), -1)
def test_middle_bits(self):
"""Extract 5 bits from the middle of a word"""
middle_bits = BitField(5, 9)
self.assertEqual(middle_bits.extract(0b1010101101101011), 0b11011)
def test_extract_low(self):
"""Extract low 3 bits"""
low_bits = BitField(0, 3)
self.assertEqual(low_bits.extract(0b10101010101), 0b0101)
def test_extract_case(self):
All_Bits = BitField(0,5)
self.assertEqual(All_Bits.extract(0b110011), 0b110011)