Drop six module usage

It was used for Python 2 backward compatibility.
No longer needed.

Author: boriel

api/utils.py

@@ -1,7 +1,6 @@
 #!/usr/bin/env python
 # -*- coding: utf-8 -*-
 
-import six
 from . import global_
 from . import errmsg
 
@@ -22,8 +21,6 @@ def read_txt_file(fname):
     for i in encodings:
         try:
             result = content.decode(i)
-            if six.PY2:
-                result = result.encode('utf-8')
             return result
         except UnicodeDecodeError:
             pass
@@ -40,7 +37,7 @@ def open_file(fname, mode='rb', encoding='utf-8'):
     :param encoding: optional encoding (string). Ignored in python2 or if not in text mode
     :return: an open file handle
     """
-    if six.PY2 or 't' not in mode:
+    if 't' not in mode:
         kwargs = {}
     else:
         kwargs = {'encoding': encoding}

requirements.txt

@@ -1,3 +1,2 @@
 ply==3.11
-six
 

setup.py

@@ -68,6 +68,6 @@ def get_files(folders):
         'Programming Language :: Python :: 3.5',
         'Programming Language :: Python :: 3.6',
     ],
-    install_requires=['six', 'ply'],
+    install_requires=['ply'],
     tags=['BASIC', 'zxspectrum', 'compiler', 'z80']
 )

symbols/string_.py

@@ -9,8 +9,6 @@
 #                    the GNU General License
 # ----------------------------------------------------------------------
 
-import six
-
 from api.constants import CLASS
 from .symbol_ import Symbol
 from .type_ import Type
@@ -44,21 +42,21 @@ def __repr__(self):
         return '"%s"' % str(self)
 
     def __eq__(self, other):
-        if isinstance(other, six.string_types):
+        if isinstance(other, str):
             return self.value == other
 
         assert isinstance(other, SymbolSTRING)
         return self.value == other.value
 
     def __gt__(self, other):
-        if type(other) in six.string_types:
+        if isinstance(other, str):
             return self.value > other
 
         assert isinstance(other, SymbolSTRING)
         return self.value > other.value
 
     def __lt__(self, other):
-        if type(other) in six.string_types:
+        if isinstance(other, str):
             return self.value < other
 
         assert isinstance(other, SymbolSTRING)

tests/functional/test_.py

@@ -2,13 +2,14 @@
 # vim:ts=4:et:ai
 
 import sys
-import six
 import os
 import doctest
 import test
 
+from io import StringIO
 
-class OutputProxy(six.StringIO):
+
+class OutputProxy(StringIO):
     """A simple interface to replace sys.stdout so
     doctest can capture it.
     """

zxb.py

@@ -9,7 +9,7 @@
 import re
 import argparse
 
-from six import StringIO
+from io import StringIO
 
 import api.debug
 import api.config

zxblex.py

@@ -677,7 +677,7 @@ def is_label(token):
     return column == 1
 
 
-lexer = lex.lex(lextab='parsetab.zxblextab')
+lexer = lex.lex()
 
 if __name__ == '__main__':  # For testing purposes
     lexer.input(open(sys.argv[1], 'rt').read())