Merge #12284: Remove assigned but never used local variables. Enable Travis checking for unused local variables.

ea04bf7862 Enable flake8 warning F841 ("local variable 'foo' is assigned to but never used") (practicalswift)
169f3e8637 Remove assigned but never used local variables (practicalswift)

Pull request description:

  Remove assigned but never used local variables. Enable Travis checking for unused local variables.

Tree-SHA512: d6052ec9044c5d1f03d874ea3c8addd5a156779213ef9200f89d3ae53230f2fd1691aff405c3dae14178e5ef09912c4432e92f606ef4a5220ed9daa140cdee81

6 files changed, 19 insertions, 18 deletions

diff --git a/contrib/devtools/github-merge.py b/contrib/devtools/github-merge.py
index 2941d2cb6d..9c666673cf 100755
--- a/contrib/devtools/github-merge.py
+++ b/contrib/devtools/github-merge.py
@@ -46,7 +46,7 @@ def git_config_get(option, default=None):
     '''
     try:
         return subprocess.check_output([GIT,'config','--get',option]).rstrip().decode('utf-8')
-    except subprocess.CalledProcessError as e:
+    except subprocess.CalledProcessError:
         return default
 
 def retrieve_pr_info(repo,pull):
@@ -193,23 +193,23 @@ def main():
     devnull = open(os.devnull,'w')
     try:
         subprocess.check_call([GIT,'checkout','-q',branch])
-    except subprocess.CalledProcessError as e:
+    except subprocess.CalledProcessError:
         print("ERROR: Cannot check out branch %s." % (branch), file=stderr)
         sys.exit(3)
     try:
         subprocess.check_call([GIT,'fetch','-q',host_repo,'+refs/pull/'+pull+'/*:refs/heads/pull/'+pull+'/*',
                                                           '+refs/heads/'+branch+':refs/heads/'+base_branch])
-    except subprocess.CalledProcessError as e:
+    except subprocess.CalledProcessError:
         print("ERROR: Cannot find pull request #%s or branch %s on %s." % (pull,branch,host_repo), file=stderr)
         sys.exit(3)
     try:
         subprocess.check_call([GIT,'log','-q','-1','refs/heads/'+head_branch], stdout=devnull, stderr=stdout)
-    except subprocess.CalledProcessError as e:
+    except subprocess.CalledProcessError:
         print("ERROR: Cannot find head of pull request #%s on %s." % (pull,host_repo), file=stderr)
         sys.exit(3)
     try:
         subprocess.check_call([GIT,'log','-q','-1','refs/heads/'+merge_branch], stdout=devnull, stderr=stdout)
-    except subprocess.CalledProcessError as e:
+    except subprocess.CalledProcessError:
         print("ERROR: Cannot find merge of pull request #%s on %s." % (pull,host_repo), file=stderr)
         sys.exit(3)
     subprocess.check_call([GIT,'checkout','-q',base_branch])
@@ -230,7 +230,7 @@ def main():
         message += '\n\nPull request description:\n\n  ' + body.replace('\n', '\n  ') + '\n'
         try:
             subprocess.check_call([GIT,'merge','-q','--commit','--no-edit','--no-ff','-m',message.encode('utf-8'),head_branch])
-        except subprocess.CalledProcessError as e:
+        except subprocess.CalledProcessError:
             print("ERROR: Cannot be merged cleanly.",file=stderr)
             subprocess.check_call([GIT,'merge','--abort'])
             sys.exit(4)
@@ -249,12 +249,12 @@ def main():
         try:
             first_sha512 = tree_sha512sum()
             message += '\n\nTree-SHA512: ' + first_sha512
-        except subprocess.CalledProcessError as e:
+        except subprocess.CalledProcessError:
             print("ERROR: Unable to compute tree hash")
             sys.exit(4)
         try:
             subprocess.check_call([GIT,'commit','--amend','-m',message.encode('utf-8')])
-        except subprocess.CalledProcessError as e:
+        except subprocess.CalledProcessError:
             print("ERROR: Cannot update message.", file=stderr)
             sys.exit(4)
 
@@ -299,7 +299,7 @@ def main():
                 try:
                     subprocess.check_call([GIT,'commit','-q','--gpg-sign','--amend','--no-edit'])
                     break
-                except subprocess.CalledProcessError as e:
+                except subprocess.CalledProcessError:
                     print("Error while signing, asking again.",file=stderr)
             elif reply == 'x':
                 print("Not signing off on merge, exiting.",file=stderr)
diff --git a/contrib/devtools/lint-python.sh b/contrib/devtools/lint-python.sh
index e2c9d775a6..1469ce1640 100755
--- a/contrib/devtools/lint-python.sh
+++ b/contrib/devtools/lint-python.sh
@@ -52,6 +52,7 @@
 # F822 undefined name name in __all__
 # F823 local variable name … referenced before assignment
 # F831 duplicate argument name in function definition
+# F841 local variable 'foo' is assigned to but never used
 # W292 no newline at end of file
 # W504 line break after binary operator
 # W601 .has_key() is deprecated, use "in"
@@ -60,4 +61,4 @@
 # W604 backticks are deprecated, use "repr()"
 # W605 invalid escape sequence "x"
 
-flake8 --ignore=B,C,E,F,I,N,W --select=E112,E113,E115,E116,E125,E131,E133,E223,E224,E271,E272,E273,E274,E275,E304,E306,E502,E702,E703,E714,E721,E741,E742,E743,F401,F402,F404,F406,F407,F601,F602,F621,F622,F631,F701,F702,F703,F704,F705,F706,F707,F811,F812,F822,F823,F831,W292,W504,W601,W602,W603,W604,W605 .
+flake8 --ignore=B,C,E,F,I,N,W --select=E112,E113,E115,E116,E125,E131,E133,E223,E224,E271,E272,E273,E274,E275,E304,E306,E502,E702,E703,E714,E721,E741,E742,E743,F401,F402,F404,F406,F407,F601,F602,F621,F622,F631,F701,F702,F703,F704,F705,F706,F707,F811,F812,F822,F823,F831,F841,W292,W504,W601,W602,W603,W604,W605 .
diff --git a/test/functional/p2p_segwit.py b/test/functional/p2p_segwit.py
index e6af35fc3d..5546bf6b29 100755
--- a/test/functional/p2p_segwit.py
+++ b/test/functional/p2p_segwit.py
@@ -833,7 +833,7 @@ class SegWitTest(BitcoinTestFramework):
             self.test_node.announce_tx_and_wait_for_getdata(tx, timeout=2)
             self.log.error("Error: duplicate tx getdata!")
             assert(False)
-        except AssertionError as e:
+        except AssertionError:
             pass
 
         # Delivering this transaction with witness should fail (no matter who
diff --git a/test/functional/test_framework/authproxy.py b/test/functional/test_framework/authproxy.py
index bd3a3b3fab..900090bb66 100644
--- a/test/functional/test_framework/authproxy.py
+++ b/test/functional/test_framework/authproxy.py
@@ -151,7 +151,7 @@ class AuthServiceProxy():
         req_start_time = time.time()
         try:
             http_response = self.__conn.getresponse()
-        except socket.timeout as e:
+        except socket.timeout:
             raise JSONRPCException({
                 'code': -344,
                 'message': '%r RPC took longer than %f seconds. Consider '
diff --git a/test/functional/test_framework/blockstore.py b/test/functional/test_framework/blockstore.py
index 6067a407cc..6073285a6c 100644
--- a/test/functional/test_framework/blockstore.py
+++ b/test/functional/test_framework/blockstore.py
@@ -87,7 +87,7 @@ class BlockStore():
         block.calc_sha256()
         try:
             self.blockDB[repr(block.sha256)] = bytes(block.serialize())
-        except TypeError as e:
+        except TypeError:
             logger.exception("Unexpected error")
         self.currentBlock = block.sha256
         self.headers_map[block.sha256] = CBlockHeader(block)
@@ -147,7 +147,7 @@ class TxStore():
         tx.calc_sha256()
         try:
             self.txDB[repr(tx.sha256)] = bytes(tx.serialize())
-        except TypeError as e:
+        except TypeError:
             logger.exception("Unexpected error")
 
     def get_transactions(self, inv):
diff --git a/test/functional/wallet_importmulti.py b/test/functional/wallet_importmulti.py
index 56ebc2622a..91acdb01d0 100755
--- a/test/functional/wallet_importmulti.py
+++ b/test/functional/wallet_importmulti.py
@@ -230,7 +230,7 @@ class ImportMultiTest (BitcoinTestFramework):
         sig_address_3 = self.nodes[0].getaddressinfo(self.nodes[0].getnewaddress())
         multi_sig_script = self.nodes[0].createmultisig(2, [sig_address_1['pubkey'], sig_address_2['pubkey'], sig_address_3['pubkey']])
         self.nodes[1].generate(100)
-        transactionid = self.nodes[1].sendtoaddress(multi_sig_script['address'], 10.00)
+        self.nodes[1].sendtoaddress(multi_sig_script['address'], 10.00)
         self.nodes[1].generate(1)
         timestamp = self.nodes[1].getblock(self.nodes[1].getbestblockhash())['mediantime']
 
@@ -257,7 +257,7 @@ class ImportMultiTest (BitcoinTestFramework):
         sig_address_3 = self.nodes[0].getaddressinfo(self.nodes[0].getnewaddress())
         multi_sig_script = self.nodes[0].createmultisig(2, [sig_address_1['pubkey'], sig_address_2['pubkey'], sig_address_3['pubkey']])
         self.nodes[1].generate(100)
-        transactionid = self.nodes[1].sendtoaddress(multi_sig_script['address'], 10.00)
+        self.nodes[1].sendtoaddress(multi_sig_script['address'], 10.00)
         self.nodes[1].generate(1)
         timestamp = self.nodes[1].getblock(self.nodes[1].getbestblockhash())['mediantime']
 
@@ -284,7 +284,7 @@ class ImportMultiTest (BitcoinTestFramework):
         sig_address_3 = self.nodes[0].getaddressinfo(self.nodes[0].getnewaddress())
         multi_sig_script = self.nodes[0].createmultisig(2, [sig_address_1['pubkey'], sig_address_2['pubkey'], sig_address_3['pubkey']])
         self.nodes[1].generate(100)
-        transactionid = self.nodes[1].sendtoaddress(multi_sig_script['address'], 10.00)
+        self.nodes[1].sendtoaddress(multi_sig_script['address'], 10.00)
         self.nodes[1].generate(1)
         timestamp = self.nodes[1].getblock(self.nodes[1].getbestblockhash())['mediantime']
 
@@ -311,7 +311,7 @@ class ImportMultiTest (BitcoinTestFramework):
         sig_address_3 = self.nodes[0].getaddressinfo(self.nodes[0].getnewaddress())
         multi_sig_script = self.nodes[0].createmultisig(2, [sig_address_1['pubkey'], sig_address_2['pubkey'], sig_address_3['pubkey']])
         self.nodes[1].generate(100)
-        transactionid = self.nodes[1].sendtoaddress(multi_sig_script['address'], 10.00)
+        self.nodes[1].sendtoaddress(multi_sig_script['address'], 10.00)
         self.nodes[1].generate(1)
         timestamp = self.nodes[1].getblock(self.nodes[1].getbestblockhash())['mediantime']