From b41d6ae3ebd0f112e6409b95546c11639f8d917e Mon Sep 17 00:00:00 2001
From: MMGen <mmgen@tuta.io>
Date: Wed, 31 Oct 2018 15:52:05 +0000
Subject: [PATCH] py3port: fix altcoin_subclass module loading magic

---
 mmgen/addr.py     |  2 +-
 mmgen/protocol.py | 14 ++++++++------
 mmgen/tw.py       |  6 +++---
 mmgen/tx.py       |  2 +-
 mmgen/util.py     | 11 ++++++++---
 5 files changed, 21 insertions(+), 14 deletions(-)

diff --git a/mmgen/addr.py b/mmgen/addr.py
index a9f2d58a..d0a0b4ca 100755
--- a/mmgen/addr.py
+++ b/mmgen/addr.py
@@ -877,7 +877,7 @@ re-import your addresses.
 	}
 
 	def __new__(cls,*args,**kwargs):
-		return MMGenObject.__new__(altcoin_subclass(cls,'tw','AddrData'),*args,**kwargs)
+		return MMGenObject.__new__(altcoin_subclass(cls,'tw','AddrData'))
 
 	def __init__(self,source=None):
 		self.al_ids = {}
diff --git a/mmgen/protocol.py b/mmgen/protocol.py
index 66d32e67..4c13b4bd 100755
--- a/mmgen/protocol.py
+++ b/mmgen/protocol.py
@@ -479,7 +479,7 @@ def init_genonly_altcoins(usr_coin,trust_level=None):
 	data = {}
 	for k in ('mainnet','testnet'):
 		data[k] = [e for e in ci.coin_constants[k] if e[6] >= trust_level]
-	exec(make_init_genonly_altcoins_str(data))
+	exec(make_init_genonly_altcoins_str(data),globals(),globals())
 	return trust_level
 
 def make_init_genonly_altcoins_str(data):
@@ -490,16 +490,18 @@ def make_init_genonly_altcoins_str(data):
 		if proto[0] in '0123456789': proto = 'X_'+proto
 		if proto in globals(): return ''
 		if coin.lower() in CoinProtocol.coins: return ''
-		def num2hexstr(n):
-			return '{:0{}x}'.format(n,2 if n < 256 else 4)
+
+		def num2hexbytes(n):
+			return "b'{:0{}x}'".format(n,(4,2)[n < 256])
+
 		o  = ['class {}(Bitcoin{}ProtocolAddrgen):'.format(proto,tn_str)]
 		o += ["base_coin = '{}'".format(coin)]
 		o += ["name = '{}'".format(e[0].lower())]
 		o += ["nameCaps = '{}'".format(e[0])]
-		a = "addr_ver_num = {{ 'p2pkh': ({!r},{!r})".format(num2hexstr(e[3][0]),e[3][1])
-		b = ", 'p2sh':  ({!r},{!r})".format(num2hexstr(e[4][0]),e[4][1]) if e[4] else ''
+		a = "addr_ver_num = {{ 'p2pkh': ({},{!r})".format(num2hexbytes(e[3][0]),e[3][1])
+		b = ", 'p2sh':  ({},{!r})".format(num2hexbytes(e[4][0]),e[4][1]) if e[4] else ''
 		o += [a+b+' }']
-		o += ["wif_ver_num = {{ 'std': {!r} }}".format(num2hexstr(e[2]))]
+		o += ["wif_ver_num = {{ 'std': {} }}".format(num2hexbytes(e[2]))]
 		o += ["mmtypes = ('L','C'{})".format(",'S'" if e[5] else '')]
 		o += ["dfl_mmtype = '{}'".format('L')]
 		return '\n\t'.join(o) + '\n'
diff --git a/mmgen/tw.py b/mmgen/tw.py
index d051ad05..c8bb544e 100755
--- a/mmgen/tw.py
+++ b/mmgen/tw.py
@@ -30,7 +30,7 @@ def CUR_RIGHT(n): return '\033[{}C'.format(n)
 class TwUnspentOutputs(MMGenObject):
 
 	def __new__(cls,*args,**kwargs):
-		return MMGenObject.__new__(altcoin_subclass(cls,'tw','TwUnspentOutputs'),*args,**kwargs)
+		return MMGenObject.__new__(altcoin_subclass(cls,'tw','TwUnspentOutputs'))
 
 	txid_w = 64
 	disp_type = 'btc'
@@ -508,7 +508,7 @@ class TwAddrList(MMGenDict):
 class TrackingWallet(MMGenObject):
 
 	def __new__(cls,*args,**kwargs):
-		return MMGenObject.__new__(altcoin_subclass(cls,'tw','TrackingWallet'),*args,**kwargs)
+		return MMGenObject.__new__(altcoin_subclass(cls,'tw','TrackingWallet'))
 
 	mode = 'r'
 	caps = ('rescan','batch')
@@ -609,7 +609,7 @@ class TwGetBalance(MMGenObject):
 	fs = '{w:13} {u:<16} {p:<16} {c}\n'
 
 	def __new__(cls,*args,**kwargs):
-		return MMGenObject.__new__(altcoin_subclass(cls,'tw','TwGetBalance'),*args,**kwargs)
+		return MMGenObject.__new__(altcoin_subclass(cls,'tw','TwGetBalance'))
 
 	def __init__(self,minconf,quiet):
 
diff --git a/mmgen/tx.py b/mmgen/tx.py
index 21f7b7cb..db423471 100755
--- a/mmgen/tx.py
+++ b/mmgen/tx.py
@@ -205,7 +205,7 @@ txio_attrs = {
 class MMGenTX(MMGenObject):
 
 	def __new__(cls,*args,**kwargs):
-		return MMGenObject.__new__(altcoin_subclass(cls,'tx','MMGenTX'),*args,**kwargs)
+		return MMGenObject.__new__(altcoin_subclass(cls,'tx','MMGenTX'))
 
 	ext      = 'rawtx'
 	raw_ext  = 'rawtx'
diff --git a/mmgen/util.py b/mmgen/util.py
index b27bb46c..5ead48b4 100755
--- a/mmgen/util.py
+++ b/mmgen/util.py
@@ -930,9 +930,14 @@ def altcoin_subclass(cls,mod_id,cls_name):
 	pname = g.proto.class_pfx if hasattr(g.proto,'class_pfx') else capfirst(g.proto.name)
 	tname = 'Token' if g.token else ''
 	e1 = 'from mmgen.altcoins.{}.{} import {}{}{}'.format(mod_dir,mod_id,pname,tname,cls_name)
-	e2 = 'cls = {}{}{}'.format(pname,tname,cls_name)
-	try: exec(e1); exec(e2); return cls
-	except ImportError: return cls
+	e2 = 'alt_cls = {}{}{}'.format(pname,tname,cls_name)
+	gl = globals()
+	try:
+		exec(e1,gl,gl)
+		exec(e2,gl,gl)
+		return alt_cls
+	except ImportError:
+		return cls
 
 # decorator for TrackingWallet
 def write_mode(orig_func):