From: Jean Privat <jean@pryen.org>
Date: Tue, 15 Sep 2015 16:59:10 +0000 (-0400)
Subject: Merge: Bytes from hexdigest
X-Git-Tag: v0.7.8~22
X-Git-Url: http://nitlanguage.org

Merge: Bytes from hexdigest

As @xymus requested in #1705, a new method is available in Text, `hexdigest_to_bytes` which transforms a regular hexdigest in its Bytes counterpart.

Ping @ppepos this could please your Pythonneous eyes

Pull-Request: #1716
Reviewed-by: Alexis Laferrière <alexis.laf@xymus.net>
Reviewed-by: Jean Privat <jean@pryen.org>
---

32b79dde9c35e1dd5a840cdc26b64cd896fb3407
diff --cc lib/core/bytes.nit
index d589646,75d7ccd..356f386
--- a/lib/core/bytes.nit
+++ b/lib/core/bytes.nit
@@@ -20,13 -20,50 +20,58 @@@ import collection::arra
  intrude import text::flat
  
  redef class Byte
 +	# Write self as a string into `ns` at position `pos`
 +	private fun add_digest_at(ns: NativeString, pos: Int) do
 +		var tmp = (0xF0u8 & self) >> 4
 +		ns[pos] = if tmp >= 0x0Au8 then tmp + 0x37u8 else tmp + 0x30u8
 +		tmp = 0x0Fu8 & self
 +		ns[pos + 1] = if tmp >= 0x0Au8 then tmp + 0x37u8 else tmp + 0x30u8
 +	end
++
+ 	# Is `self` a valid hexadecimal digit (in ASCII)
+ 	#
+ 	# ~~~nit
+ 	# intrude import core::bytes
+ 	# assert not '/'.ascii.to_b.is_valid_hexdigit
+ 	# assert '0'.ascii.to_b.is_valid_hexdigit
+ 	# assert '9'.ascii.to_b.is_valid_hexdigit
+ 	# assert not ':'.ascii.to_b.is_valid_hexdigit
+ 	# assert not '@'.ascii.to_b.is_valid_hexdigit
+ 	# assert 'A'.ascii.to_b.is_valid_hexdigit
+ 	# assert 'F'.ascii.to_b.is_valid_hexdigit
+ 	# assert not 'G'.ascii.to_b.is_valid_hexdigit
+ 	# assert not '`'.ascii.to_b.is_valid_hexdigit
+ 	# assert 'a'.ascii.to_b.is_valid_hexdigit
+ 	# assert 'f'.ascii.to_b.is_valid_hexdigit
+ 	# assert not 'g'.ascii.to_b.is_valid_hexdigit
+ 	# ~~~
+ 	private fun is_valid_hexdigit: Bool do
+ 		return (self >= 0x30u8 and self <= 0x39u8) or
+ 		       (self >= 0x41u8 and self <= 0x46u8) or
+ 		       (self >= 0x61u8 and self <= 0x66u8)
+ 	end
+ 
+ 	# `self` as a hexdigit to its byte value
+ 	#
+ 	# ~~~nit
+ 	# intrude import core::bytes
+ 	# assert 0x39u8.hexdigit_to_byteval == 0x09u8
+ 	# assert 0x43u8.hexdigit_to_byteval == 0x0Cu8
+ 	# ~~~
+ 	#
+ 	# REQUIRE: `self.is_valid_hexdigit`
+ 	private fun hexdigit_to_byteval: Byte do
+ 		if self >= 0x30u8 and self <= 0x39u8 then
+ 			return self - 0x30u8
+ 		else if self >= 0x41u8 and self <= 0x46u8 then
+ 			return self - 0x37u8
+ 		else if self >= 0x61u8 and self <= 0x66u8 then
+ 			return self - 0x57u8
+ 		end
+ 		# Happens only if the requirement is not met.
+ 		# i.e. this abort is here to please the compiler
+ 		abort
+ 	end
  end
  
  # A buffer containing Byte-manipulation facilities