ruff RUF015 (prefer next(...) over single element slice)

mmgen/addrdata.py

@@ -51,7 +51,7 @@ class AddrData(MMGenObject):
 
 	def coinaddr2mmaddr(self, coinaddr):
 		d = self.make_reverse_dict([coinaddr])
-		return (list(d.values())[0][0]) if d else None
+		return next(iter(d.values()))[0] if d else None
 
 	def add(self, addrlist):
 		if isinstance(addrlist, AddrList):

mmgen/color.py

@@ -68,7 +68,7 @@ def get_terminfo_colors(term=None):
 		return None
 	else:
 		set_vt100()
-		s = [e.split('#')[1] for e in cmdout.split(',') if e.startswith('colors')][0]
+		s = next(iter(e.split('#', 1)[1] for e in cmdout.split(',') if e.startswith('colors')))
 		from .util import is_hex_str
 		if s.isdecimal():
 			return int(s)

mmgen/daemon.py

@@ -255,7 +255,7 @@ class Daemon(Lockable):
 			die(2, f'Unable to execute {cls.exec_fn}')
 		else:
 			res = cp.stdout.splitlines()
-			return (res[0] if len(res) == 1 else [s for s in res if 'ersion' in s][0]).strip()
+			return (res[0] if len(res) == 1 else next(s for s in res if 'ersion' in s)).strip()
 
 class RPCDaemon(Daemon):
 

mmgen/proto/btc/rpc/local.py

@@ -354,7 +354,7 @@ class BitcoinRPCClient(RPCClient, metaclass=AsyncInit):
 			self.daemon.cfg_file)
 
 	def get_daemon_cfg_option(self, req_key):
-		return list(self.get_daemon_cfg_options([req_key]).values())[0]
+		return next(iter(self.get_daemon_cfg_options([req_key]).values()))
 
 	def get_daemon_cfg_options(self, req_keys):
 

mmgen/protocol.py

@@ -92,7 +92,7 @@ class CoinProtocol(MMGenObject):
 			if hasattr(self, 'addr_ver_info'):
 				self.addr_ver_bytes = {bytes.fromhex(k): v for k, v in self.addr_ver_info.items()}
 				self.addr_fmt_to_ver_bytes = {v: k for k, v in self.addr_ver_bytes.items()}
-				self.addr_ver_bytes_len = len(list(self.addr_ver_bytes)[0])
+				self.addr_ver_bytes_len = len(next(iter(self.addr_ver_bytes)))
 
 			if gc.cmd_caps:
 				for cap in gc.cmd_caps.caps:

mmgen/tw/view.py

@@ -673,7 +673,7 @@ class TwView(MMGenObject, metaclass=AsyncInit):
 		async def do_error_msg():
 			msg_r(
 				'Choice must be a single number between {n} and {m} inclusive{s}'.format(
-					n = list(data.keys())[0] if is_addr_idx else 1,
+					n = next(iter(data.keys())) if is_addr_idx else 1,
 					m = list(data.keys())[-1] if is_addr_idx else len(data),
 					s = ' ' if self.scroll else ''))
 			if self.scroll:

mmgen/tx/keys.py

@@ -128,7 +128,7 @@ class TxKeys:
 					ignore_in_fmt = True,
 					passwd_file = self.passwdfile).seed
 			elif self.saved_seeds and subseeds_checked is False:
-				seed = self.saved_seeds[list(self.saved_seeds)[0]].subseed_by_seed_id(sid, print_msg=True)
+				seed = self.saved_seeds[next(iter(self.saved_seeds))].subseed_by_seed_id(sid, print_msg=True)
 				subseeds_checked = True
 				if not seed:
 					continue

pyproject.toml

@@ -29,7 +29,6 @@ ignore = [
 	"PLW1510", # `subprocess.run` without explicit `check` argument
 	"RET501", # Do not explicitly `return None` in function if it is the only possible return value
 	"RUF012", # Mutable default value for class attribute
-	"RUF015", # Prefer `next(s for s in res if 'ersion' in s)` over single element slice
 	"RUF022", # `__all__` is not sorted
 	"RUF100", # Unused `noqa` directive (non-enabled: `F401`)
 	"S102", # Use of `exec` detected

test/cmdtest_d/httpd/etherscan.py

@@ -29,7 +29,7 @@ class EtherscanServer(HTTPD):
 				target = 'result'
 				length = int(environ.get('CONTENT_LENGTH', '0'))
 				qs = environ['wsgi.input'].read(length).decode()
-				tx = [s for s in qs.split('&') if 'RawTx=' in s][0].split('=')[1]
+				tx = next(s for s in qs.split('&') if 'RawTx=' in s).split('=')[1]
 				keccak_256 = get_keccak()
 				txid = '0x' + keccak_256(bytes.fromhex(tx[2:])).hexdigest()
 

test/cmdtest_d/regtest.py

@@ -1510,7 +1510,7 @@ class CmdTestRegtest(CmdTestBase, CmdTestShared):
 		assert self.proto.cap('segwit')
 		if not hasattr(self, '_b_start_'):
 			t = self.spawn('mmgen-tool', ['--color=0', '--bob', 'listaddresses'], no_msg=True)
-			self._b_start_ = int([e for e in t.read().split('\n') if ':B:1' in e][0].split()[0].rstrip(')'))
+			self._b_start_ = int(next(e for e in t.read().split('\n') if ':B:1' in e).split(maxsplit=1)[0].rstrip(')'))
 			t.close()
 		return self._b_start_
 
@@ -1677,7 +1677,7 @@ class CmdTestRegtest(CmdTestBase, CmdTestShared):
 	def alice_add_comment_coinaddr(self):
 		mmid = self._user_sid('alice') + (':S:1', ':L:1')[self.proto.coin=='BCH']
 		t = self.spawn('mmgen-tool', ['--alice', 'listaddress', mmid, 'wide=true'], no_msg=True)
-		addr = [i for i in strip_ansi_escapes(t.read()).splitlines() if re.search(rf'\b{mmid}\b', i)][0].split()[3]
+		addr = next(i for i in strip_ansi_escapes(t.read()).splitlines() if re.search(rf'\b{mmid}\b', i)).split()[3]
 		return self.user_add_comment('alice', addr, 'Label added using coin address of MMGen address')
 
 	def alice_chk_comment_coinaddr(self):

test/cmdtest_d/shared.py

@@ -73,7 +73,7 @@ class CmdTestShared:
 			e2 = fr'Using .*{auto_chg_addr}.* as.*address'
 			res = t.expect([e1, e2], regex=True)
 			if res == 0:
-				choice = [s.split(')')[0].lstrip() for s in t.p.match[0].split('\n') if auto_chg_addr in s][0]
+				choice = next(s.split(')', 1)[0].lstrip() for s in t.p.match[0].split('\n') if auto_chg_addr in s)
 				t.send(f'{choice}\n')
 				t.expect(e2, regex=True)
 			t.send('y')

test/cmdtest_d/swap.py

@@ -581,7 +581,7 @@ class CmdTestSwap(CmdTestSwapMethods, CmdTestRegtest, CmdTestAutosignThreaded):
 	def fund_bob_recv_subwallet(self, proto_idx=1, amt='5'):
 		coin_arg = f'--coin={self.protos[proto_idx].coin}'
 		t = self.spawn('mmgen-tool', ['--bob', coin_arg, 'listaddresses'])
-		addr = [s for s in strip_ansi_escapes(t.read()).splitlines() if 'C:1 No' in s][0].split()[3]
+		addr = next(s for s in strip_ansi_escapes(t.read()).splitlines() if 'C:1 No' in s).split()[3]
 		t = self.spawn(
 			'mmgen-regtest',
 			[coin_arg, 'send', addr, str(amt)],

test/modtest_d/subseed.py

@@ -63,14 +63,14 @@ class unit_tests:
 			assert len(s_lines) == nSubseeds + 4, s
 
 			a = seed.subseed('2L').sid
-			b = [e for e in s_lines if ' 2L:' in e][0].strip().split()[1]
+			b = next(e for e in s_lines if ' 2L:' in e).strip().split()[1]
 			assert a == b, b
 
 			c = seed.subseed('2').sid
 			assert c == a, c
 
 			a = seed.subseed('5S').sid
-			b = [e for e in s_lines if ' 5S:' in e][0].strip().split()[3]
+			b = next(e for e in s_lines if ' 5S:' in e).strip().split()[3]
 			assert a == b, b
 
 			s = seed.subseeds.format(nSubseeds+1, nSubseeds+2)
@@ -79,7 +79,7 @@ class unit_tests:
 
 			ss_idx = str(nSubseeds+2) + 'S'
 			a = seed.subseed(ss_idx).sid
-			b = [e for e in s_lines if f' {ss_idx}:' in e][0].strip().split()[3]
+			b = next(e for e in s_lines if f' {ss_idx}:' in e).strip().split()[3]
 			assert a == b, b
 
 			s = seed.subseeds.format(1, 10)

test/modtest_d/util.py

@@ -33,11 +33,11 @@ class unit_tests:
 
 		}
 
-		col1_w = max(len(str(e)) for e in list(chks.values())[0]) + 1
+		col1_w = max(len(str(e)) for e in next(iter(chks.values()))) + 1
 
 		for _name, sample in samples.items():
 			vmsg(cyan(f'Input: {sample}'))
-			for fmt in list(chks.values())[0]:
+			for fmt in next(iter(chks.values())):
 				spc = '\n' if fmt in ('col', 'list') else ' '
 				indent = '    + ' if fmt == 'col' else ''
 				res = fmt_list(sample, fmt=fmt, indent=indent) if fmt else fmt_list(sample, indent=indent)
@@ -82,11 +82,11 @@ class unit_tests:
 		}
 		}
 
-		col1_w = max(len(str(e)) for e in list(chks.values())[0]) + 1
+		col1_w = max(len(str(e)) for e in next(iter(chks.values()))) + 1
 
 		for _name, sample in samples.items():
 			vmsg(cyan(f'Input: {sample}'))
-			for fmt in list(chks.values())[0]:
+			for fmt in next(iter(chks.values())):
 				res = fmt_dict(sample, fmt=fmt) if fmt else fmt_dict(sample)
 				vmsg(f'  {str(fmt)+":":{col1_w}} {res}')
 				if _name in chks:

test/objtest.py

@@ -80,7 +80,7 @@ def run_test(mod, test, arg, input_data, arg1, exc_name):
 				del arg['arg']
 			else:
 				args = []
-				ret_chk = list(arg.values())[0] # assume only one key present
+				ret_chk = next(iter(arg.values())) # assume only one key present
 			if 'ret' in arg:
 				ret_chk = arg['ret']
 				del arg['ret']