Optimize bytes.fromhex() and bytearray.fromhex()
Issue #25401: Optimize bytes.fromhex() and bytearray.fromhex(): they are now
between 2x and 3.5x faster. Changes:
* Use a fast-path working on a char* string for ASCII string
* Use a slow-path for non-ASCII string
* Replace slow hex_digit_to_int() function with a O(1) lookup in
_PyLong_DigitValue precomputed table
* Use _PyBytesWriter API to handle the buffer
* Add unit tests to check the error position in error messages
diff --git a/Lib/test/test_bytes.py b/Lib/test/test_bytes.py
index 947d959..0fe33b5 100644
--- a/Lib/test/test_bytes.py
+++ b/Lib/test/test_bytes.py
@@ -301,6 +301,20 @@
self.assertRaises(ValueError, self.type2test.fromhex, '\x00')
self.assertRaises(ValueError, self.type2test.fromhex, '12 \x00 34')
+ for data, pos in (
+ # invalid first hexadecimal character
+ ('12 x4 56', 3),
+ # invalid second hexadecimal character
+ ('12 3x 56', 4),
+ # two invalid hexadecimal characters
+ ('12 xy 56', 3),
+ # test non-ASCII string
+ ('12 3\xff 56', 4),
+ ):
+ with self.assertRaises(ValueError) as cm:
+ self.type2test.fromhex(data)
+ self.assertIn('at position %s' % pos, str(cm.exception))
+
def test_hex(self):
self.assertRaises(TypeError, self.type2test.hex)
self.assertRaises(TypeError, self.type2test.hex, 1)