remove unused imports in cqlsh.py and cqlshlib

patch by Brad Schoening; reviewed by Stefan Miklosovic and Brandon Williams for CASSANDRA-17413

CHANGES.txt

@@ -1,4 +1,5 @@
 4.1
+ * remove unused imports in cqlsh.py and cqlshlib (CASSANDRA-17413)
  * deprecate property windows_timer_interval (CASSANDRA-17404)
  * Expose streaming as a vtable (CASSANDRA-17390)
  * Make startup checks configurable (CASSANDRA-17220)

bin/cqlsh.py

@@ -16,8 +16,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from __future__ import division, unicode_literals, print_function
-
 import cmd
 import codecs
 import csv
@@ -37,7 +35,7 @@ from contextlib import contextmanager
 from glob import glob
 from uuid import UUID
 
-if sys.version_info < (3, 6) and sys.version_info[0:2] != (2, 7):
+if sys.version_info < (3, 6):
     sys.exit("\ncqlsh requires Python 3.6+\n")
 
 # see CASSANDRA-10428
@@ -140,8 +138,7 @@ from cassandra.auth import PlainTextAuthProvider
 from cassandra.cluster import Cluster
 from cassandra.cqltypes import cql_typename
 from cassandra.marshal import int64_unpack
-from cassandra.metadata import (ColumnMetadata, KeyspaceMetadata,
-                                TableMetadata, protect_name, protect_names)
+from cassandra.metadata import (ColumnMetadata, KeyspaceMetadata, TableMetadata)
 from cassandra.policies import WhiteListRoundRobinPolicy
 from cassandra.query import SimpleStatement, ordered_dict_factory, TraceUnavailable
 from cassandra.util import datetime_from_timestamp
@@ -152,15 +149,15 @@ cqlshlibdir = os.path.join(CASSANDRA_PATH, 'pylib')
 if os.path.isdir(cqlshlibdir):
     sys.path.insert(0, cqlshlibdir)
 
-from cqlshlib import cql3handling, cqlhandling, pylexotron, sslhandling, cqlshhandling
+from cqlshlib import cql3handling, pylexotron, sslhandling, cqlshhandling
 from cqlshlib.copyutil import ExportTask, ImportTask
 from cqlshlib.displaying import (ANSI_RESET, BLUE, COLUMN_NAME_COLORS, CYAN,
                                  RED, WHITE, FormattedValue, colorme)
 from cqlshlib.formatting import (DEFAULT_DATE_FORMAT, DEFAULT_NANOTIME_FORMAT,
                                  DEFAULT_TIMESTAMP_FORMAT, CqlType, DateTimeFormat,
-                                 format_by_type, formatter_for)
+                                 format_by_type)
 from cqlshlib.tracing import print_trace, print_trace_session
-from cqlshlib.util import get_file_encoding_bomsize, trim_if_present
+from cqlshlib.util import get_file_encoding_bomsize
 
 DEFAULT_HOST = '127.0.0.1'
 DEFAULT_PORT = 9042

pylib/cqlshlib/copyutil.py

@@ -16,7 +16,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from __future__ import unicode_literals
 import csv
 import datetime
 import json
@@ -33,6 +32,7 @@ import sys
 import threading
 import time
 import traceback
+import errno
 
 from bisect import bisect_right
 from calendar import timegm
@@ -51,7 +51,7 @@ from six.moves.queue import Queue
 
 from cassandra import OperationTimedOut
 from cassandra.cluster import Cluster, DefaultConnection
-from cassandra.cqltypes import ReversedType, UserType, BytesType, VarcharType
+from cassandra.cqltypes import ReversedType, UserType, VarcharType
 from cassandra.metadata import protect_name, protect_names, protect_value
 from cassandra.policies import RetryPolicy, WhiteListRoundRobinPolicy, DCAwareRoundRobinPolicy, FallthroughRetryPolicy
 from cassandra.query import BatchStatement, BatchType, SimpleStatement, tuple_factory
@@ -201,6 +201,7 @@ class ReceivingChannels(object):
             try:
                 readable, _, _ = select(self._readers, [], [], timeout)
             except select.error as exc:
+                # TODO: PEP 475 in Python 3.5 should make this unnecessary
                 # Do not abort on window resize:
                 if exc[0] != errno.EINTR:
                     raise

pylib/cqlshlib/cqlhandling.py

@@ -111,12 +111,6 @@ class CqlParsingRuleSet(pylexotron.ParsingRuleSet):
                     # don't put any 'endline' tokens in output
                     continue
 
-            # Convert all unicode tokens to ascii, where possible.  This
-            # helps avoid problems with performing unicode-incompatible
-            # operations on tokens (like .lower()).  See CASSANDRA-9083
-            # for one example of this.
-            str_token = t[1]
-
             curstmt.append(t)
             if t[0] == 'endtoken':
                 term_on_nl = False

pylib/cqlshlib/displaying.py

@@ -14,8 +14,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from __future__ import unicode_literals
-
 from collections import defaultdict
 
 RED = '\033[0;1;31m'

pylib/cqlshlib/formatting.py

@@ -14,8 +14,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from __future__ import unicode_literals
-
 import binascii
 import calendar
 import datetime
@@ -23,7 +21,6 @@ import math
 import os
 import re
 import sys
-import platform
 
 from six import ensure_text
 

pylib/cqlshlib/test/__init__.py

@@ -13,5 +13,3 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-
-from .cassconnect import create_db, remove_db

pylib/cqlshlib/test/ansi_colors.py

@@ -14,8 +14,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from __future__ import unicode_literals
-
 import re
 import six
 
@@ -65,6 +63,7 @@ for colordef in color_defs:
     for c in nameset:
         colors_by_name[c] = colorcode
 
+
 class ColoredChar(object):
     def __init__(self, c, colorcode):
         self.c = c
@@ -104,6 +103,7 @@ class ColoredChar(object):
     def colortag(self):
         return lookup_letter_from_code(self._colorcode)
 
+
 class ColoredText(object):
     def __init__(self, source=''):
         if isinstance(source, six.text_type):
@@ -152,7 +152,6 @@ class ColoredText(object):
 
     @staticmethod
     def parse_sgr_param(curclr, paramstr):
-        oldclr = curclr
         args = list(map(int, paramstr.split(';')))
         for a in args:
             if a == 0:
@@ -179,15 +178,19 @@ class ColoredText(object):
     def colortags(self):
         return ''.join([c.colortag() for c in self.chars])
 
+
 def lookup_colorcode(name):
     return colors_by_name[name]
 
+
 def lookup_colorname(code):
     return colors_by_num.get(code, 'Unknown-color-0%o' % code)
 
+
 def lookup_colorletter(letter):
     return colors_by_letter[letter]
 
+
 def lookup_letter_from_code(code):
     letr = letters_by_num.get(code, ' ')
     if letr == 'n':

pylib/cqlshlib/test/cassconnect.py

@@ -157,7 +157,8 @@ def cql_rule_set():
     return CqlRuleSet
 
 
-class DEFAULTVAL: pass
+class DEFAULTVAL:
+    pass
 
 
 __TEST__ = False

pylib/cqlshlib/test/run_cqlsh.py

@@ -16,18 +16,15 @@
 
 # NOTE: this testing tool is *nix specific
 
-from __future__ import unicode_literals
-
 import os
 import sys
 import re
 import contextlib
 import subprocess
 import signal
-import math
 from time import time
 from . import basecase
-from os.path import join, normpath
+from os.path import join
 
 
 import pty
@@ -42,6 +39,7 @@ except AttributeError:
     # Python 3.7+
     Pattern = re.Pattern
 
+
 def get_smm_sequence(term='xterm'):
     """
     Return the set meta mode (smm) sequence, if any.
@@ -57,10 +55,12 @@ def get_smm_sequence(term='xterm'):
             result = result.decode("utf-8")
     return result
 
+
 DEFAULT_SMM_SEQUENCE = get_smm_sequence()
 
 cqlshlog = basecase.cqlshlog
 
+
 def set_controlling_pty(master, slave):
     os.setsid()
     os.close(master)
@@ -70,6 +70,7 @@ def set_controlling_pty(master, slave):
         os.close(slave)
     os.close(os.open(os.ttyname(1), os.O_RDWR))
 
+
 @contextlib.contextmanager
 def raising_signal(signum, exc):
     """
@@ -85,9 +86,11 @@ def raising_signal(signum, exc):
     finally:
         signal.signal(signum, oldhandlr)
 
+
 class TimeoutError(Exception):
     pass
 
+
 @contextlib.contextmanager
 def timing_out(seconds):
     if seconds is None:
@@ -107,6 +110,7 @@ def timing_out(seconds):
 def noop(*a):
     pass
 
+
 class ProcRunner:
     def __init__(self, path, tty=True, env=None, args=()):
         self.exe_path = path
@@ -222,6 +226,7 @@ class ProcRunner:
             curtime = time()
         return got
 
+
 class CqlshRunner(ProcRunner):
     def __init__(self, path=None, host=None, port=None, keyspace=None, cqlver=None,
                  args=(), prompt=DEFAULT_CQLSH_PROMPT, env=None, tty=True, **kwargs):
@@ -256,7 +261,7 @@ class CqlshRunner(ProcRunner):
             self.output_header = self.read_to_next_prompt()
 
     def read_to_next_prompt(self, timeout=10.0):
-        return self.read_until(self.prompt, timeout=timeout, ptty_timeout=3, replace=[DEFAULT_SMM_SEQUENCE,])
+        return self.read_until(self.prompt, timeout=timeout, ptty_timeout=3, replace=[DEFAULT_SMM_SEQUENCE])
 
     def read_up_to_timeout(self, timeout, blksize=4096):
         output = ProcRunner.read_up_to_timeout(self, timeout, blksize=blksize)
@@ -281,12 +286,14 @@ class CqlshRunner(ProcRunner):
             promptline = output
             output = ''
         assert re.match(self.prompt, DEFAULT_PREFIX + promptline), \
-                'last line of output %r does not match %r?' % (promptline, self.prompt)
+            'last line of output %r does not match %r?' % (promptline, self.prompt)
         return output + '\n'
 
+
 def run_cqlsh(**kwargs):
     return contextlib.closing(CqlshRunner(**kwargs))
 
+
 def call_cqlsh(**kwargs):
     kwargs.setdefault('prompt', None)
     proginput = kwargs.pop('input', '')

pylib/cqlshlib/test/test_copyutil.py

@@ -20,7 +20,7 @@
 
 import unittest
 
-from cassandra.metadata import MIN_LONG, Murmur3Token, TokenMap
+from cassandra.metadata import MIN_LONG, Murmur3Token
 from cassandra.policies import SimpleConvictionPolicy
 from cassandra.pool import Host
 from unittest.mock import Mock
@@ -75,7 +75,7 @@ class TestExportTask(CopyTaskTest):
         }
         # merge override options with standard options
         overridden_opts = dict(self.opts)
-        for k,v in opts.items():
+        for k, v in opts.items():
             overridden_opts[k] = v
         export_task = ExportTask(shell, self.ks, self.table, self.columns, self.fname, overridden_opts, self.protocol_version, self.config_file)
         assert export_task.get_ranges() == expected_ranges
@@ -93,19 +93,19 @@ class TestExportTask(CopyTaskTest):
         self._test_get_ranges_murmur3_base({'begintoken': 1, 'endtoken': -1}, {})
 
         # simple case of a single range
-        expected_ranges = {(1,2): {'hosts': ('10.0.0.4', '10.0.0.1', '10.0.0.2'), 'attempts': 0, 'rows': 0, 'workerno': -1}}
+        expected_ranges = {(1, 2): {'hosts': ('10.0.0.4', '10.0.0.1', '10.0.0.2'), 'attempts': 0, 'rows': 0, 'workerno': -1}}
         self._test_get_ranges_murmur3_base({'begintoken': 1, 'endtoken': 2}, expected_ranges)
 
         # simple case of two contiguous ranges
         expected_ranges = {
-            (-4611686018427387903,0): {'hosts': ('10.0.0.3', '10.0.0.4', '10.0.0.1'), 'attempts': 0, 'rows': 0, 'workerno': -1},
-            (0,1): {'hosts': ('10.0.0.4', '10.0.0.1', '10.0.0.2'), 'attempts': 0, 'rows': 0, 'workerno': -1}
+            (-4611686018427387903, 0): {'hosts': ('10.0.0.3', '10.0.0.4', '10.0.0.1'), 'attempts': 0, 'rows': 0, 'workerno': -1},
+            (0, 1): {'hosts': ('10.0.0.4', '10.0.0.1', '10.0.0.2'), 'attempts': 0, 'rows': 0, 'workerno': -1}
         }
         self._test_get_ranges_murmur3_base({'begintoken': -4611686018427387903, 'endtoken': 1}, expected_ranges)
 
         # specify a begintoken only (endtoken defaults to None)
         expected_ranges = {
-            (4611686018427387905,None): {'hosts': ('10.0.0.1', '10.0.0.2', '10.0.0.3'), 'attempts': 0, 'rows': 0, 'workerno': -1}
+            (4611686018427387905, None): {'hosts': ('10.0.0.1', '10.0.0.2', '10.0.0.3'), 'attempts': 0, 'rows': 0, 'workerno': -1}
         }
         self._test_get_ranges_murmur3_base({'begintoken': 4611686018427387905}, expected_ranges)
 
@@ -114,4 +114,3 @@ class TestExportTask(CopyTaskTest):
             (None, MIN_LONG + 1): {'hosts': ('10.0.0.2', '10.0.0.3', '10.0.0.4'), 'attempts': 0, 'rows': 0, 'workerno': -1}
         }
         self._test_get_ranges_murmur3_base({'endtoken': MIN_LONG + 1}, expected_ranges)
-

pylib/cqlshlib/test/test_cql_parsing.py

@@ -778,12 +778,12 @@ class TestCqlParsing(TestCase):
 
 
 def parse_cqlsh_statements(text):
-    '''
+    """
     Runs its argument through the sequence of parsing steps that cqlsh takes its
     input through.
 
     Currently does not handle batch statements.
-    '''
+    """
     # based on onecmd
     statements, _ = CqlRuleSet.cql_split_statements(text)
     # stops here. For regular cql commands, onecmd just splits it and sends it
@@ -799,13 +799,13 @@ def tokens_with_types(lexed):
 
 
 def strip_final_empty_items(xs):
-    '''
+    """
     Returns its a copy of argument as a list, but with any terminating
     subsequence of falsey values removed.
 
     >>> strip_final_empty_items([[3, 4], [5, 6, 7], [], [], [1], []])
     [[3, 4], [5, 6, 7], [], [], [1]]
-    '''
+    """
     rv = list(xs)
 
     while rv and not rv[-1]:

pylib/cqlshlib/test/test_cqlsh_completion.py

@@ -38,6 +38,7 @@ COMPLETION_RESPONSE_TIME = 0.5
 
 completion_separation_re = re.compile(r'\s+')
 
+
 class CqlshCompletionCase(BaseTestCase):
 
     @classmethod
@@ -52,7 +53,7 @@ class CqlshCompletionCase(BaseTestCase):
         env = os.environ.copy()
         env['COLUMNS'] = '100000'
         if (locale.getpreferredencoding() != 'UTF-8'):
-             env['LC_CTYPE'] = 'en_US.utf8'
+            env['LC_CTYPE'] = 'en_US.utf8'
         self.cqlsh_runner = testrun_cqlsh(cqlver=None, env=env)
         self.cqlsh = self.cqlsh_runner.__enter__()
 
@@ -150,7 +151,6 @@ class CqlshCompletionCase(BaseTestCase):
                 # retry once
                 self.cqlsh.send(CTRL_C)
                 self.cqlsh.read_to_next_prompt(timeout=10.0)
- 
 
     def strategies(self):
         return CqlRuleSet.replication_strategies
@@ -680,7 +680,7 @@ class TestCqlshCompletion(CqlshCompletionCase):
                                      'timestamp_resolution', 'min_threshold', 'class', 'max_threshold',
                                      'tombstone_compaction_interval', 'tombstone_threshold',
                                      'enabled', 'unchecked_tombstone_compaction',
-                                     'only_purge_repaired_tombstones','provide_overlapping_tombstones'])
+                                     'only_purge_repaired_tombstones', 'provide_overlapping_tombstones'])
 
     def test_complete_in_create_columnfamily(self):
         self.trycompletions('CREATE C', choices=['COLUMNFAMILY', 'CUSTOM'])

pylib/cqlshlib/test/test_cqlsh_output.py

@@ -17,8 +17,6 @@
 # to configure behavior, define $CQL_TEST_HOST to the destination address
 # and $CQL_TEST_PORT to the associated port.
 
-from __future__ import unicode_literals, with_statement
-
 import locale
 import os
 import re

pylib/cqlshlib/test/test_unicode.py

@@ -15,10 +15,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from __future__ import unicode_literals, with_statement
-
 import os
-import subprocess
 
 from .basecase import BaseTestCase
 from .cassconnect import (get_cassandra_connection, create_keyspace, testrun_cqlsh)
@@ -71,5 +68,5 @@ class TestCqlshUnicode(BaseTestCase):
             output = c.cmd_and_response('CREATE TYPE "%s" ( "%s" int );' % (v1, v2))
             output = c.cmd_and_response('DESC TYPES;')
             self.assertIn(v1, output)
-            output = c.cmd_and_response('DESC TYPE "%s";' %(v1,))
+            output = c.cmd_and_response('DESC TYPE "%s";' % (v1,))
             self.assertIn(v2, output)

pylib/cqlshlib/test/winpty.py

@@ -47,4 +47,4 @@ class WinPty(object):
                 count = count + 1
         except Empty:
             pass
-        return buf.getvalue()
+        return buf.getvalue()

pylib/cqlshlib/tracing.py

@@ -19,7 +19,6 @@ import time
 
 from cassandra.query import QueryTrace, TraceUnavailable
 from cqlshlib.displaying import MAGENTA
-from cqlshlib.formatting import CqlType
 
 
 def print_trace_session(shell, session, session_id, partial_session=False):