From c894598551f1f130d8f195356f4f8af8a5b85d59 Mon Sep 17 00:00:00 2001
From: The MMGen Project <mmgen@tuta.io>
Date: Tue, 23 Sep 2025 09:20:55 +0000
Subject: [PATCH] sub-level mods: use match statement where practicable (4
 files)

---
 mmgen/bip_hd/__init__.py    |  9 +++++----
 mmgen/bip_hd/chainparams.py | 15 ++++++++-------
 mmgen/tool/coin.py          | 17 +++++++++--------
 mmgen/tx/__init__.py        | 25 +++++++++++++------------
 4 files changed, 35 insertions(+), 31 deletions(-)

diff --git a/mmgen/bip_hd/__init__.py b/mmgen/bip_hd/__init__.py
index 1f37d414..a72fcfca 100644
--- a/mmgen/bip_hd/__init__.py
+++ b/mmgen/bip_hd/__init__.py
@@ -128,10 +128,11 @@ def get_bip_by_addr_type(addr_type):
 		44)
 
 def check_privkey(key_int):
-	if key_int == 0:
-		raise ValueError('private key is zero!')
-	elif key_int >= secp256k1_order:
-		raise ValueError(f'{key_int:x}: private key >= group order!')
+	match key_int:
+		case 0:
+			raise ValueError('private key is zero!')
+		case n if n >= secp256k1_order:
+			raise ValueError(f'{n:x}: private key >= group order!')
 
 class BipHDConfig(Lockable):
 
diff --git a/mmgen/bip_hd/chainparams.py b/mmgen/bip_hd/chainparams.py
index 27500a9e..7045ae54 100644
--- a/mmgen/bip_hd/chainparams.py
+++ b/mmgen/bip_hd/chainparams.py
@@ -48,13 +48,14 @@ def parse_data():
 			key = line[1:-1]
 			continue
 		p = parse_line(line)
-		if key in out:
-			out[key][p[1]] = p
-		elif key == 'defaults':
-			out['defaults'] = p
-			defaults = p
-		else:
-			out[key] = {p[1]: p}
+		match key:
+			case k if k in out:
+				out[key][p[1]] = p
+			case 'defaults':
+				out['defaults'] = p
+				defaults = p
+			case _:
+				out[key] = {p[1]: p}
 
 	return out
 
diff --git a/mmgen/tool/coin.py b/mmgen/tool/coin.py
index fbc49d71..fe747557 100755
--- a/mmgen/tool/coin.py
+++ b/mmgen/tool/coin.py
@@ -165,14 +165,15 @@ class tool_cmd(tool_cmd_base):
 	def pubhash2addr(self, pubhashhex: 'sstr'):
 		"convert public key hash to address"
 		pubhash = bytes.fromhex(pubhashhex)
-		if self.mmtype.name == 'segwit':
-			return self.proto.pubhash2segwitaddr(pubhash)
-		elif self.mmtype.name == 'bech32':
-			return self.proto.pubhash2bech32addr(pubhash)
-		elif self.mmtype.name == 'bech32x':
-			return self.proto.encode_addr_bech32x(pubhash)
-		else:
-			return self.proto.pubhash2addr(pubhash, self.mmtype.addr_fmt)
+		match self.mmtype.name:
+			case 'segwit':
+				return self.proto.pubhash2segwitaddr(pubhash)
+			case 'bech32':
+				return self.proto.pubhash2bech32addr(pubhash)
+			case 'bech32x':
+				return self.proto.encode_addr_bech32x(pubhash)
+			case _:
+				return self.proto.pubhash2addr(pubhash, self.mmtype.addr_fmt)
 
 	def addr2pubhash(self, addr: 'sstr'):
 		"convert coin address to public key hash"
diff --git a/mmgen/tx/__init__.py b/mmgen/tx/__init__.py
index 692243b9..6d2f5b08 100755
--- a/mmgen/tx/__init__.py
+++ b/mmgen/tx/__init__.py
@@ -39,18 +39,19 @@ def _get_cls_info(clsname, modname, kwargs):
 		raise ValueError(
 			f"{clsname} must be instantiated with 'proto', 'data' or 'filename' keyword")
 
-	if clsname == 'Completed':
-		from ..util import get_extension, die
-		from .completed import Completed
-		ext = get_extension(kwargs['filename'])
-		cls = Completed.ext_to_cls(ext, proto)
-		if not cls:
-			die(1, f'{ext!r}: unrecognized file extension for CompletedTX')
-		clsname = cls.__name__
-		modname = cls.__module__.rsplit('.', maxsplit=1)[-1]
-	elif clsname == 'New' and kwargs['target'] == 'swaptx':
-		clsname = 'NewSwap'
-		modname = 'new_swap'
+	match clsname:
+		case 'Completed':
+			from ..util import get_extension, die
+			from .completed import Completed
+			ext = get_extension(kwargs['filename'])
+			cls = Completed.ext_to_cls(ext, proto)
+			if not cls:
+				die(1, f'{ext!r}: unrecognized file extension for CompletedTX')
+			clsname = cls.__name__
+			modname = cls.__module__.rsplit('.', maxsplit=1)[-1]
+		case 'New' if kwargs['target'] == 'swaptx':
+			clsname = 'NewSwap'
+			modname = 'new_swap'
 
 	kwargs['proto'] = proto