Merge #853: Fix remaining flake8 errors and add linter script

ab439617f3 Add flake8 linter script (Kristaps Kaupe)
512fab735a Fix remaining flake8 errors (Kristaps Kaupe)

Pull request description:

Top commit has no ACKs.

Tree-SHA512: 73cd6e308dbe8f387eaf4203a35778aa22fc229231cb6624f66c1412a4041a20ecc4b842b0ad411fcd018002486b9c6016a4f2ae0c95c9480478ca6f5d8b878d

conftest.py

@@ -17,7 +17,7 @@ def get_bitcoind_version(version_string):
     # this utility function returns the version number
     # as a tuple in the form (major, minor, patch)
     version_tuple = re.match(
-        b'.*v(?P<major>\d+)\.(?P<minor>\d+)\.(?P<patch>\d+)',
+        br'.*v(?P<major>\d+)\.(?P<minor>\d+)\.(?P<patch>\d+)',
         version_string).groups()
     return tuple(map(lambda x: int(x), version_tuple))
 

jmbase/jmbase/twisted_utils.py

@@ -2,7 +2,7 @@
 from zope.interface import implementer
 from twisted.internet.error import ReactorNotRunning
 from twisted.internet import reactor, defer
-from twisted.internet.endpoints import TCP4ClientEndpoint
+from twisted.internet.endpoints import TCP4ClientEndpoint, UNIXClientEndpoint
 from twisted.web.client import Agent, BrowserLikePolicyForHTTPS
 import txtorcon
 from txtorcon.web import tor_agent

jmdaemon/jmdaemon/daemon_protocol.py

@@ -415,8 +415,8 @@ class SNICKERDaemonServerProtocol(HTTPPassThrough):
 
     @SNICKERReceiverGetProposals.responder
     def on_SNICKER_RECEIVER_GET_PROPOSALS(self):
-        for server in self.servers:
-            self.getRequest(server, self.receive_proposals_from_server)
+        for srv in self.servers:
+            self.getRequest(srv, self.receive_proposals_from_server)
         return {'accepted': True}
 
     def receive_proposals_from_server(self, response, server):

scripts/snicker/snicker-finder.py

@@ -24,6 +24,7 @@ in Bitcoin Core in order to get full transactions, since it
 parses the raw blocks.
 """
 
+import sys
 from optparse import OptionParser
 from jmbase import bintohex, EXIT_ARGERROR, jmprint
 import jmbitcoin as btc

scripts/snicker/snicker-recovery.py

@@ -24,6 +24,7 @@ keys, so as a reminder, *always* back up either jmdat wallet files,
 or at least, the imported keys themselves.)
 """
 
+import sys
 from optparse import OptionParser
 from jmbase import bintohex, EXIT_ARGERROR, jmprint
 import jmbitcoin as btc

test/lint/lint-python.sh

@@ -0,0 +1,16 @@
+#!/usr/bin/env bash
+# Based on Bitcoin Core's test/lint/lint-python.sh
+
+if ! command -v flake8 > /dev/null; then
+    echo "Skipping Python linting since flake8 is not installed."
+    exit 0
+elif flake8 --version | grep -q "Python 2"; then
+    echo "Skipping Python linting since flake8 is running under Python 2. Install the Python 3 version of flake8."
+    exit 0
+fi
+
+if [[ $# == 0 ]]; then
+    flake8 $(git ls-files "*.py")
+else
+    flake8 "$@"
+fi