flake8: make flake8 better and more strict

this removes some unused variables and also catches a couple bugs

.flake8

@@ -1,17 +1,13 @@
 [flake8]
 filename =
     *.py,
-    trezorctl
+    ./trezorctl
 exclude =
     .tox/,
     build/,
     dist/,
-    trezorlib/*_pb2.py
+    vendor/,
 ignore =
-    # F821 undefined name 'unicode'
-    F821,
-    # F841 local variable is assigned to but never used
-    F841,
     # F401: module imported but unused
     F401,
     # F403: used import *

.travis.yml

@@ -29,7 +29,7 @@ install:
 
 script:
     - python setup.py install
-    - flake8 . trezorctl --exclude=vendor
+    - flake8
     - tox
 
 notifications:

tools/signtest.py

@@ -111,7 +111,7 @@ class MyTxApiBitcoin(object):
 
             txser = self.serialize_tx(t)
             txhash = tools.Hash(txser)[::-1]
-            outi = self.inputs.append(
+            self.inputs.append(
                 proto_types.TxInputType(
                     address_n=self.client.expand_path("44'/0'/0'/0/%d" % idx),
                     script_type=(
@@ -178,15 +178,15 @@ def main():
     # Get the first address of first BIP44 account
     # (should be the same address as shown in wallet.trezor.io)
 
-    outputs = [
-        proto_types.TxOutputType(
-            amount=0,
-            script_type=proto_types.PAYTOADDRESS,
-            address='p2xtZoXeX5X8BP8JfFhQK2nD3emtjch7UeFm'
-            # op_return_data=binascii.unhexlify('2890770995194662774cd192ee383b805e9a066e6a456be037727649228fb7f6')
-            # address_n=client.expand_path("44'/0'/0'/0/35"),
-            # address='3PUxV6Cc4udQZQsJhArVUzvvVoKC8ohkAj',
-        ),
+    # outputs = [
+    #     proto_types.TxOutputType(
+    #         amount=0,
+    #         script_type=proto_types.PAYTOADDRESS,
+    #         address='p2xtZoXeX5X8BP8JfFhQK2nD3emtjch7UeFm'
+    #         # op_return_data=binascii.unhexlify('2890770995194662774cd192ee383b805e9a066e6a456be037727649228fb7f6')
+    #         # address_n=client.expand_path("44'/0'/0'/0/35"),
+    #         # address='3PUxV6Cc4udQZQsJhArVUzvvVoKC8ohkAj',
+    #     ),
     #     proto_types.TxOutputType(
     #         amount=0,
     #         script_type=proto_types.PAYTOOPRETURN,
@@ -213,7 +213,7 @@ def main():
     #     # address='1PtCkQgyN6xHmXWzLmFFrDNA5vYhYLeNFZ',
     #     # address='1NcMqUvyWv1K3Zxwmx5sqfj7ZEmPCSdJFM',
     #     ),
-    ]
+    # ]
 
 #    (signatures, serialized_tx) = client.sign_tx('Testnet', inputs, outputs)
     (signatures, serialized_tx) = client.sign_tx('Bitcoin', txstore.get_inputs(), txstore.get_outputs())

trezorctl

@@ -233,7 +233,7 @@ def set_homescreen(connect, filename):
     elif filename.endswith('.toif'):
         img = open(filename, 'rb').read()
         if img[:8] != b'TOIf\x90\x00\x90\x00':
-            raise CallException(types.Failure_DataError, 'File is not a TOIF file with size of 144x144')
+            raise CallException(proto.FailureType.DataError, 'File is not a TOIF file with size of 144x144')
     else:
         from PIL import Image
         im = Image.open(filename)

trezorlib/client.py

@@ -42,11 +42,6 @@ from .protobuf import MessageType
 if sys.version_info.major < 3:
     raise Exception("Trezorlib does not support Python 2 anymore.")
 
-# try:
-#     from PIL import Image
-#     SCREENSHOT = True
-# except:
-#     SCREENSHOT = False
 
 SCREENSHOT = False
 
@@ -424,6 +419,7 @@ class DebugLinkMixin(object):
     def call_raw(self, msg):
 
         if SCREENSHOT and self.debug:
+            from PIL import Image
             layout = self.debug.read_layout()
             im = Image.new("RGB", (128, 64))
             pix = im.load()
@@ -804,7 +800,7 @@ class ProtocolMixin(object):
     @session
     def sign_tx(self, coin_name, inputs, outputs, version=None, lock_time=None, debug_processor=None):
 
-        start = time.time()
+        # start = time.time()
         txes = self._prepare_sign_tx(inputs, outputs)
 
         # Prepare and send initial message

trezorlib/transport/__init__.py

@@ -115,4 +115,4 @@ def get_transport(path=None, prefix_search=False):
     if transports:
         return transports[0].find_by_path(path, prefix_search=prefix_search)
 
-    raise Exception("Unknown path prefix '%s'" % prefix)
+    raise Exception("Could not find device by path: {}".format(path))

trezorlib/transport/udp.py

@@ -67,7 +67,6 @@ class UdpTransport(Transport):
 
     @classmethod
     def enumerate(cls):
-        devices = []
         default_path = '{}:{}'.format(cls.DEFAULT_HOST, cls.DEFAULT_PORT)
         try:
             return [cls._try_path(default_path)]