pylint: Avoid W0102 (dangerous argument)

Despite the reviews we have some W0102s that potentially corrupts the
arguments. Let's get rid of them.
Signed-off-by: NLukáš Doktor <ldoktor@redhat.com>

avocado/core/dispatcher.py

@@ -34,7 +34,9 @@ class Dispatcher(EnabledExtensionManager):
     #: Default namespace prefix for Avocado extensions
     NAMESPACE_PREFIX = 'avocado.plugins.'
 
-    def __init__(self, namespace, invoke_kwds={}):
+    def __init__(self, namespace, invoke_kwds=None):
+        if invoke_kwds is None:
+            invoke_kwds = {}
         self.load_failures = []
         super(Dispatcher, self).__init__(namespace=namespace,
                                          check_func=self.enabled,

avocado/utils/gdb.py

@@ -543,7 +543,7 @@ class GDB(object):
             raise UnexpectedResponseError
         return r
 
-    def run(self, args=[]):
+    def run(self, args=None):
         """
         Runs the application inside the debugger
 

avocado/utils/wait.py

@@ -4,7 +4,7 @@ import time
 log = logging.getLogger('avocado.test')
 
 
-def wait_for(func, timeout, first=0.0, step=1.0, text=None, args=[], kwargs={}):
+def wait_for(func, timeout, first=0.0, step=1.0, text=None, args=None, kwargs=None):
     """
     Wait until func() evaluates to True.
 
@@ -18,6 +18,10 @@ def wait_for(func, timeout, first=0.0, step=1.0, text=None, args=[], kwargs={}):
     :param args: Positional arguments to func
     :param kwargs: Keyword arguments to func
     """
+    if args is None:
+        args = []
+    if kwargs is None:
+        kwargs = {}
     start_time = time.time()
     end_time = time.time() + timeout
 

selftests/unit/test_job.py

@@ -24,7 +24,9 @@ class JobTest(unittest.TestCase):
         self.tmpdir = tempfile.mkdtemp(prefix="avocado_" + __name__)
 
     @staticmethod
-    def _find_simple_test_candidates(candidates=['true', 'time', 'uptime']):
+    def _find_simple_test_candidates(candidates=None):
+        if candidates is None:
+            candidates = ['true', 'time', 'uptime']
         found = []
         for candidate in candidates:
             try: