pylint: Enable useless-suppression globally.

We deactivate it locally where needed, i.e. where we are sure it's some
platform-specific thing.

.pylintrc

@@ -9,6 +9,7 @@ load-plugins=pylint_checkers.config,
              pylint_checkers.settrace
 
 [MESSAGES CONTROL]
+enable=all
 disable=no-self-use,
         fixme,
         global-statement,
@@ -30,7 +31,8 @@ disable=no-self-use,
         wrong-import-order,
         ungrouped-imports,
         wrong-import-position,
-        redefined-variable-type
+        redefined-variable-type,
+        suppressed-message
 
 [BASIC]
 function-rgx=[a-z_][a-z0-9_]{2,50}$

qutebrowser/browser/network/networkmanager.py

@@ -57,7 +57,8 @@ class SslError(QSslError):
     def __hash__(self):
         try:
             # Qt >= 5.4
-            return super().__hash__()  # pylint: disable=not-callable
+            # pylint: disable=not-callable,useless-suppression
+            return super().__hash__()
         except TypeError:
             return hash((self.certificate().toDer(), self.error()))
 

qutebrowser/commands/userscripts.py

@@ -44,8 +44,8 @@ class _QtFIFOReader(QObject):
         # See http://www.outflux.net/blog/archives/2008/03/09/using-select-on-a-fifo/
         # We also use os.open and os.fdopen rather than built-in open so we
         # can add O_NONBLOCK.
-        fd = os.open(filepath, os.O_RDWR |
+        # pylint: disable=no-member,useless-suppression
-                     os.O_NONBLOCK)  # pylint: disable=no-member
+        fd = os.open(filepath, os.O_RDWR | os.O_NONBLOCK)
         self.fifo = os.fdopen(fd, 'r')
         self._notifier = QSocketNotifier(fd, QSocketNotifier.Read, self)
         self._notifier.activated.connect(self.read_line)
@@ -175,7 +175,8 @@ class _POSIXUserscriptRunner(_BaseUserscriptRunner):
             # exist, it shouldn't be a big issue.
             self._filepath = tempfile.mktemp(prefix='qutebrowser-userscript-',
                                              dir=standarddir.runtime())
-            os.mkfifo(self._filepath)  # pylint: disable=no-member
+            # pylint: disable=no-member,useless-suppression
+            os.mkfifo(self._filepath)
         except OSError as e:
             message.error(self._win_id, "Error while creating FIFO: {}".format(
                 e))

qutebrowser/misc/crashsignal.py

@@ -308,7 +308,7 @@ class SignalHandler(QObject):
             signal.SIGTERM, self.interrupt)
 
         if os.name == 'posix' and hasattr(signal, 'set_wakeup_fd'):
-            # pylint: disable=import-error,no-member
+            # pylint: disable=import-error,no-member,useless-suppression
             import fcntl
             read_fd, write_fd = os.pipe()
             for fd in (read_fd, write_fd):

qutebrowser/misc/earlyinit.py

@@ -123,7 +123,8 @@ def init_faulthandler(fileobj=sys.__stderr__):
     faulthandler.enable(fileobj)
     if hasattr(faulthandler, 'register') and hasattr(signal, 'SIGUSR1'):
         # If available, we also want a traceback on SIGUSR1.
-        faulthandler.register(signal.SIGUSR1)  # pylint: disable=no-member
+        # pylint: disable=no-member,useless-suppression
+        faulthandler.register(signal.SIGUSR1)
 
 
 def fix_harfbuzz(args):

qutebrowser/utils/log.py

@@ -259,7 +259,7 @@ def qt_message_handler(msg_type, context, msg):
         QtCore.QtFatalMsg: logging.CRITICAL,
     }
     try:
-        # pylint: disable=no-member
+        # pylint: disable=no-member,useless-suppression
         qt_to_logging[QtCore.QtInfoMsg] = logging.INFO
     except AttributeError:
         # Qt < 5.5

scripts/dev/freeze.py

@@ -29,7 +29,7 @@ import os.path
 import sys
 import distutils
 
-import cx_Freeze as cx  # pylint: disable=import-error
+import cx_Freeze as cx  # pylint: disable=import-error,useless-suppression
 # cx_Freeze is hard to install (needs C extensions) so we don't check for it.
 
 sys.path.insert(0, os.path.join(os.path.dirname(__file__), os.pardir,

scripts/dev/freeze_tests.py

@@ -26,7 +26,7 @@ import os.path
 import sys
 import contextlib
 
-import cx_Freeze as cx  # pylint: disable=import-error
+import cx_Freeze as cx  # pylint: disable=import-error,useless-suppression
 # cx_Freeze is hard to install (needs C extensions) so we don't check for it.
 import pytest
 

tests/unit/misc/test_ipc.py

@@ -316,7 +316,7 @@ class TestListen:
 
     @pytest.mark.posix
     def test_permissions_posix(self, ipc_server):
-        # pylint: disable=no-member
+        # pylint: disable=no-member,useless-suppression
         ipc_server.listen()
         sockfile = ipc_server._server.fullServerName()
         sockdir = os.path.dirname(sockfile)

tests/unit/utils/test_qtutils.py

@@ -25,7 +25,8 @@ import sys
 import operator
 import os.path
 try:
-    from test import test_file  # pylint: disable=no-name-in-module
+    # pylint: disable=no-name-in-module,useless-suppression
+    from test import test_file
 except ImportError:
     # Debian patches Python to remove the tests...
     test_file = None
@@ -748,10 +749,11 @@ class TestPyQIODevice:
 
     def test_seek_unsupported(self, pyqiodev):
         """Test seeking with unsupported whence arguments."""
+        # pylint: disable=no-member,useless-suppression
         if hasattr(os, 'SEEK_HOLE'):
-            whence = os.SEEK_HOLE  # pylint: disable=no-member
+            whence = os.SEEK_HOLE
         elif hasattr(os, 'SEEK_DATA'):
-            whence = os.SEEK_DATA  # pylint: disable=no-member
+            whence = os.SEEK_DATA
         else:
             pytest.skip("Needs os.SEEK_HOLE or os.SEEK_DATA available.")
         pyqiodev.open(QIODevice.ReadOnly)