pylint: Fix used-before-assignment

> Emitted when a local variable is accessed before its assignment took
place. Assignments in try blocks are assumed not to have occurred when
evaluating associated except/finally blocks. Assignments in except
blocks are assumed not to have occurred when evaluating statements
outside the block, except when the associated try block contains a
return statement.

Fixes: https://pagure.io/freeipa/issue/9278
Signed-off-by: Stanislav Levin <slev@altlinux.org>
Reviewed-By: Stanislav Levin <slev@altlinux.org>

ipaclient/install/ipa_client_samba.py

@@ -39,8 +39,8 @@ logger.setLevel(logging.DEBUG)
 @contextmanager
 def use_api_as_principal(principal, keytab):
     with ipautil.private_ccache() as ccache_file:
+        old_principal = getattr(context, "principal", None)
         try:
-            old_principal = getattr(context, "principal", None)
             name = gssapi.Name(principal, gssapi.NameType.kerberos_principal)
             store = {"ccache": ccache_file, "client_keytab": keytab}
             gssapi.Credentials(name=name, usage="initiate", store=store)
@@ -63,9 +63,7 @@ def use_api_as_principal(principal, keytab):
         finally:
             if api.Backend.rpcclient.isconnected():
                 api.Backend.rpcclient.disconnect()
-            # pylint: disable=used-before-assignment
             setattr(context, "principal", old_principal)
-            # pylint: enable=used-before-assignment
 
 
 def parse_options():

ipapython/ipaldap.py

@@ -1082,6 +1082,7 @@ class LDAPClient:
     def error_handler(self, arg_desc=None):
         """Context manager that handles LDAPErrors
         """
+        desc = None
         try:
             try:
                 yield
@@ -1101,7 +1102,7 @@ class LDAPClient:
         except ldap.TYPE_OR_VALUE_EXISTS:
             # attribute type or attribute value already exists, usually only
             # occurs, when two machines try to write at the same time.
-            raise errors.DuplicateEntry(message=desc)  # pylint: disable=E0601
+            raise errors.DuplicateEntry(message=desc)
         except ldap.CONSTRAINT_VIOLATION:
             # This error gets thrown by the uniqueness plugin
             _msg = 'Another entry with the same attribute value already exists'

ipaserver/install/adtrustinstance.py

@@ -388,13 +388,14 @@ class ADTRUSTInstance(service.Service):
 
             # Abort if RID bases are too close
             local_range = ranges_with_no_rid_base[0]
+            size_value = local_range.single_value.get('ipaIDRangeSize')
             try:
-                size = int(local_range.single_value.get('ipaIDRangeSize'))
+                size = int(size_value)
-            except ValueError:
+            except (ValueError, TypeError):
-                # pylint: disable=used-before-assignment
+                raise RuntimeError(
-                raise RuntimeError('ipaIDRangeSize is set to a non-integer '
+                    "ipaIDRangeSize is set to a non-integer value or is not set"
-                                   'value or is not set at all (got {val})'
+                    f" at all (got {size_value!r})"
-                                   .format(val=size))
+                ) from None
 
             if abs(self.rid_base - self.secondary_rid_base) < size:
                 self.print_msg("Primary and secondary RID base are too close. "

ipaserver/install/installutils.py

@@ -1559,10 +1559,8 @@ def default_ca_subject_dn(subject_base):
 
 
 def validate_mask():
-    try:
+    mask = os.umask(0)
-        mask = os.umask(0)
+    os.umask(mask)
-    finally:
-        os.umask(mask)  # pylint: disable=used-before-assignment
     mask_str = None
     if mask & 0b111101101 > 0:
         mask_str = "{:04o}".format(mask)

ipaserver/install/krbinstance.py

@@ -436,8 +436,8 @@ class KrbInstance(service.Service):
         krbtgt = "krbtgt/" + self.realm + "@" + self.realm
         certpath = (paths.KDC_CERT, paths.KDC_KEY)
 
+        prev_helper = None
         try:
-            prev_helper = None
             # on the first CA-ful master without '--no-pkinit', we issue the
             # certificate by contacting Dogtag directly
             ca_instances = find_providing_servers(
@@ -482,7 +482,6 @@ class KrbInstance(service.Service):
                 logger.error("Failed to initiate the request: %s", e)
             return
         finally:
-            # pylint: disable-next=used-before-assignment
             if prev_helper is not None:
                 certmonger.modify_ca_helper(certmonger_ca, prev_helper)
 

ipatests/test_cmdline/test_ipagetkeytab.py

@@ -44,8 +44,8 @@ from contextlib import contextmanager
 @contextmanager
 def use_keytab(principal, keytab):
     with private_ccache() as ccache_file:
+        old_principal = getattr(context, 'principal', None)
         try:
-            old_principal = getattr(context, 'principal', None)
             name = gssapi.Name(principal, gssapi.NameType.kerberos_principal)
             store = {'ccache': ccache_file,
                      'client_keytab': keytab}
@@ -60,7 +60,6 @@ def use_keytab(principal, keytab):
                             'principal %s in %s: %s' % (principal, keytab,
                                                         str(e)))
         finally:
-            # pylint: disable-next=used-before-assignment
             setattr(context, 'principal', old_principal)
 
 

ipatests/test_integration/test_trust.py

@@ -657,14 +657,15 @@ class TestTrust(BaseTestTrust):
 
         try:
             # stop sssd_be, needed to simulate a timeout in the extdom plugin.
-            stop_sssdbe = self.master.run_command('kill -STOP %s' % pid)
+            self.master.run_command('kill -STOP %s' % pid)
-            client.run_command(test_id)
+            try:
-            error = 'ldap_extended_operation result: No such object(32)'
+                client.run_command(test_id)
-            sssd_log2 = client.get_file_contents(log_file)[logsize:]
+                error = 'ldap_extended_operation result: No such object(32)'
-            assert error.encode() not in sssd_log2
+                sssd_log2 = client.get_file_contents(log_file)[logsize:]
-        finally:
+                assert error.encode() not in sssd_log2
-            if stop_sssdbe.returncode == 0:  # pylint: disable=E0601
+            finally:
                 self.master.run_command('kill -CONT %s' % pid)
+        finally:
             # reconnect and set back to default extdom plugin
             conn = self.master.ldap_connect()
             entry = conn.get_entry(extdom_dn)

ipatests/test_xmlrpc/tracker/caacl_plugin.py

@@ -49,7 +49,7 @@ class CAACLTracker(Tracker):
                    u'usercategory', u'hostcategory', u'ipacacategory',
                    u'servicecategory', u'ipaenabledflag', u'objectclass',
                    u'ipauniqueid'}
-    update_keys = create_keys - {u'dn'}
+    update_keys = retrieve_keys - {"dn"}
 
     def __init__(self, name, ipacertprofile_category=None, user_category=None,
                  service_category=None, host_category=None,
@@ -158,7 +158,7 @@ class CAACLTracker(Tracker):
     def make_update_command(self, updates):
         return self.make_command('caacl_mod', self.name, **updates)
 
-    def update(self, updates, expected_updates=None, silent=False):
+    def update(self, updates, expected_updates=None):
         """If removing a category, delete it from tracker as well"""
         # filter out empty categories and track changes
 
@@ -166,11 +166,7 @@ class CAACLTracker(Tracker):
         for key, value in updates.items():
             if key in self.category_keys:
                 if not value:
-                    try:
+                    del self.attrs[key]
-                        del self.attrs[key]
-                    except IndexError:
-                        if silent:
-                            pass
                 else:
                     # if there is a value, prepare the pair for update
                     filtered_updates.update({key: value})
@@ -185,14 +181,13 @@ class CAACLTracker(Tracker):
         try:
             result = command()
         except errors.EmptyModlist:
-            if silent:
+            pass
-                self.attrs.update(filtered_updates)
+        else:
-                self.attrs.update(expected_updates)
+            self.attrs.update(filtered_updates)
-                # pylint: disable=used-before-assignment
+            self.attrs.update(expected_updates)
-                self.check_update(result,
+            self.check_update(result,
-                                  extra_keys=set(self.update_keys) |
+                              extra_keys=set(self.update_keys) |
-                                  set(expected_updates.keys()))
+                              set(expected_updates.keys()))
-                # pylint: enable=used-before-assignment
 
     def check_update(self, result, extra_keys=()):
         assert_deepequal(dict(

ipatests/test_xmlrpc/xmlrpc_test.py

@@ -136,13 +136,13 @@ def fuzzy_set_optional_oc(s, oc):
                  == set(y.lower() for y in s if y != oc))
 
 
+server_available = None
 try:
     if not api.Backend.rpcclient.isconnected():
         api.Backend.rpcclient.connect()
-    res = api.Command['user_show'](u'notfound')
+    api.Command["user_show"]("notfound")
-except errors.NetworkError:
+    server_available = True
-    server_available = False
+except (errors.NetworkError, IOError):
-except IOError:
     server_available = False
 except errors.NotFound:
     server_available = True
@@ -202,7 +202,7 @@ class XMLRPC_test:
     """
     @pytest.fixture(autouse=True, scope="class")
     def xmlrpc_setup(self, request):
-        if not server_available:  # pylint: disable=used-before-assignment
+        if not server_available:
             pytest.skip('%r: Server not available: %r' %
                         (request.cls.__module__,
                          api.env.xmlrpc_uri))
@@ -345,6 +345,7 @@ class Declarative(XMLRPC_test):
     def check_exception(self, nice, cmd, args, options, expected):
         klass = expected.__class__
         expected_name = klass.__name__
+        got = None
         try:
             output = api.Command[cmd](*args, **options)
         except Exception as e:
@@ -353,7 +354,7 @@ class Declarative(XMLRPC_test):
             raise AssertionError(
                 EXPECTED % (cmd, expected_name, args, options, output)
             )
-        if not isinstance(got, klass):  # pylint: disable=used-before-assignment
+        if not isinstance(got, klass):
             raise AssertionError(
                 UNEXPECTED % (cmd, expected_name, args, options,
                               expected_name, expected,