Remove support for end-of-life Pythons

Python 2.7 and 3.4 are end-of-life. They are no longer receiving bug
fixes, including for security issues. Python 2.7 went EOL on 2020-01-01
and 3.4 on 2019-03-18. For additional details on support Python
versions, see:

Supported: https://devguide.python.org/#status-of-python-branches
EOL: https://devguide.python.org/devcycle/#end-of-life-branches

Removing support for EOL Pythons will reduce testing and maintenance
resources while allowing the library to move towards modern Python 3.

Using pypinfo, we can show the PyPI download statistics, showing less
than 10% of users are using Python 2.7.

| python_version | percent | download_count |
| -------------- | ------: | -------------: |
| 3.7            |  45.36% |      3,056,010 |
| 3.6            |  26.46% |      1,782,778 |
| 3.8            |  12.22% |        823,213 |
| 2.7            |   9.97% |        671,459 |
| 3.5            |   5.86% |        394,846 |
| 3.4            |   0.10% |          6,700 |
| 3.9            |   0.03% |          2,346 |
| 2.6            |   0.00% |             57 |
| 3.3            |   0.00% |             21 |
| 3.10           |   0.00% |              6 |
| Total          |         |      6,737,436 |

Library users who continue to use Python 2.7 will still be able to
install previous versions of sqlparse.

Compatibility shims have been dropped, simplifying the code.

Using pyupgrade, the codebase has been updated to take advantage of
modern syntax <https://github.com/asottile/pyupgrade>.

The wheel is no longer marked as "universal" as it is now Python 3 only.

1 files changed, 17 insertions, 23 deletions

diff --git a/sqlparse/cli.py b/sqlparse/cli.py
index 25555a5..957d220 100755
--- a/sqlparse/cli.py
+++ b/sqlparse/cli.py
@@ -1,5 +1,4 @@
 #!/usr/bin/env python
-# -*- coding: utf-8 -*-
 #
 # Copyright (C) 2009-2018 the sqlparse authors and contributors
 # <see AUTHORS file>
@@ -23,10 +22,8 @@ Why does this file exist, and why not put this in __main__?
 import argparse
 import sys
 from io import TextIOWrapper
-from codecs import open, getreader
 
 import sqlparse
-from sqlparse.compat import PY2
 from sqlparse.exceptions import SQLParseError
 
 
@@ -62,16 +59,16 @@ def create_parser():
         metavar='CHOICE',
         dest='keyword_case',
         choices=_CASE_CHOICES,
-        help='change case of keywords, CHOICE is one of {0}'.format(
-            ', '.join('"{0}"'.format(x) for x in _CASE_CHOICES)))
+        help='change case of keywords, CHOICE is one of {}'.format(
+            ', '.join('"{}"'.format(x) for x in _CASE_CHOICES)))
 
     group.add_argument(
         '-i', '--identifiers',
         metavar='CHOICE',
         dest='identifier_case',
         choices=_CASE_CHOICES,
-        help='change case of identifiers, CHOICE is one of {0}'.format(
-            ', '.join('"{0}"'.format(x) for x in _CASE_CHOICES)))
+        help='change case of identifiers, CHOICE is one of {}'.format(
+            ', '.join('"{}"'.format(x) for x in _CASE_CHOICES)))
 
     group.add_argument(
         '-l', '--language',
@@ -153,7 +150,7 @@ def create_parser():
 
 def _error(msg):
     """Print msg and optionally exit with return code exit_."""
-    sys.stderr.write(u'[ERROR] {0}\n'.format(msg))
+    sys.stderr.write('[ERROR] {}\n'.format(msg))
     return 1
 
 
@@ -162,29 +159,26 @@ def main(args=None):
     args = parser.parse_args(args)
 
     if args.filename == '-':  # read from stdin
-        if PY2:
-            data = getreader(args.encoding)(sys.stdin).read()
-        else:
-            wrapper = TextIOWrapper(sys.stdin.buffer, encoding=args.encoding)
-            try:
-                data = wrapper.read()
-            finally:
-                wrapper.detach()
+        wrapper = TextIOWrapper(sys.stdin.buffer, encoding=args.encoding)
+        try:
+            data = wrapper.read()
+        finally:
+            wrapper.detach()
     else:
         try:
-            with open(args.filename, 'r', args.encoding) as f:
+            with open(args.filename, encoding=args.encoding) as f:
                 data = ''.join(f.readlines())
-        except IOError as e:
+        except OSError as e:
             return _error(
-                u'Failed to read {0}: {1}'.format(args.filename, e))
+                'Failed to read {}: {}'.format(args.filename, e))
 
     close_stream = False
     if args.outfile:
         try:
-            stream = open(args.outfile, 'w', args.encoding)
+            stream = open(args.outfile, 'w', encoding=args.encoding)
             close_stream = True
-        except IOError as e:
-            return _error(u'Failed to open {0}: {1}'.format(args.outfile, e))
+        except OSError as e:
+            return _error('Failed to open {}: {}'.format(args.outfile, e))
     else:
         stream = sys.stdout
 
@@ -192,7 +186,7 @@ def main(args=None):
     try:
         formatter_opts = sqlparse.formatter.validate_options(formatter_opts)
     except SQLParseError as e:
-        return _error(u'Invalid options: {0}'.format(e))
+        return _error('Invalid options: {}'.format(e))
 
     s = sqlparse.format(data, **formatter_opts)
     stream.write(s)