replace basestring by six.string_types

src/sage/algebras/commutative_dga.py

@@ -62,6 +62,7 @@
 #                  http://www.gnu.org/licenses/
 #*****************************************************************************
 
+import six
 from sage.structure.unique_representation import UniqueRepresentation
 from sage.structure.sage_object import SageObject
 from sage.misc.cachefunc import cached_method
@@ -832,7 +833,7 @@ def __classcall__(cls, base, names=None, degrees=None, R=None, I=None):
             else:
                 n = len(degrees)
             names = tuple('x{}'.format(i) for i in range(n))
-        elif isinstance(names, basestring):
+        elif isinstance(names, six.string_types):
             names = tuple(names.split(','))
             n = len(names)
         else:

src/sage/algebras/free_algebra.py

@@ -128,6 +128,7 @@
 #                  http://www.gnu.org/licenses/
 #*****************************************************************************
 
+import six
 from sage.categories.rings import Rings
 
 from sage.monoids.free_monoid import FreeMonoid
@@ -594,7 +595,7 @@ def exp_to_monomial(T):
                     return M(out)
                 return self.element_class(self, dict([(exp_to_monomial(T),c) for T,c in x.letterplace_polynomial().dict().iteritems()]))
         # ok, not a free algebra element (or should not be viewed as one).
-        if isinstance(x, basestring):
+        if isinstance(x, six.string_types):
             from sage.all import sage_eval
             G = self.gens()
             d = {str(v): G[i] for i,v in enumerate(self.variable_names())}

src/sage/algebras/shuffle_algebra.py

@@ -15,6 +15,7 @@
 #                  http://www.gnu.org/licenses/
 #*****************************************************************************
 
+import six
 from sage.categories.rings import Rings
 from sage.categories.algebras_with_basis import AlgebrasWithBasis
 from sage.categories.commutative_algebras import CommutativeAlgebras
@@ -379,7 +380,7 @@ def _element_constructor_(self, x):
         if isinstance(P, DualPBWBasis):
             return self(P.expansion(x))
         # ok, not a shuffle algebra element (or should not be viewed as one).
-        if isinstance(x, basestring):
+        if isinstance(x, six.string_types):
             from sage.misc.sage_eval import sage_eval
             return sage_eval(x,locals=self.gens_dict())
         R = self.base_ring()

src/sage/categories/pushout.py

@@ -1,6 +1,7 @@
 """
 Coercion via Construction Functors
 """
+import six
 from functor import Functor
 from basic import *
 
@@ -1431,10 +1432,10 @@ def __init__(self, var, multi_variate=False):
 
         """
         Functor.__init__(self, Rings(), Rings())
-        if not isinstance(var, (basestring,tuple,list)):
+        if not isinstance(var, (six.string_types,tuple,list)):
             raise TypeError("variable name or list of variable names expected")
         self.var = var
-        self.multi_variate = multi_variate or not isinstance(var, basestring)
+        self.multi_variate = multi_variate or not isinstance(var, six.string_types)
 
     def _apply_functor(self, R):
         """
@@ -2367,7 +2368,7 @@ def __init__(self, I, names=None, as_field=False):
         self.I = I
         if names is None:
             self.names = None
-        elif isinstance(names, basestring):
+        elif isinstance(names, six.string_types):
             self.names = (names,)
         else:
             self.names = tuple(names)

src/sage/coding/source_coding/huffman.py

@@ -29,6 +29,7 @@
 # http://www.gnu.org/licenses/
 ###########################################################################
 
+import six
 from sage.structure.sage_object import SageObject
 
 ###########################################################################
@@ -245,7 +246,7 @@ def __init__(self, source):
         # index of each alphabetic symbol
         self._index = None
 
-        if isinstance(source,basestring):
+        if isinstance(source, six.string_types):
             self._build_code(frequency_table(source))
         elif isinstance(source, dict):
             self._build_code(source)

src/sage/combinat/root_system/plot.py

@@ -561,6 +561,7 @@
 #                  http://www.gnu.org/licenses/
 #*****************************************************************************
 
+import six
 from sage.misc.cachefunc import cached_method, cached_function
 from sage.misc.latex import latex
 from sage.misc.lazy_import import lazy_import
@@ -741,13 +742,13 @@ def text(self, label, position, rgbcolor=(0,0,0)):
         """
         if self.labels:
             if self.dimension <= 2:
-                if not isinstance(label, basestring):
+                if not isinstance(label, six.string_types):
                     label = "$"+str(latex(label))+"$"
                 from sage.plot.text import text
                 return text(label, position, fontsize=15, rgbcolor=rgbcolor)
             elif self.dimension == 3:
                 # LaTeX labels not yet supported in 3D
-                if isinstance(label, basestring):
+                if isinstance(label, six.string_types):
                     label = label.replace("{","").replace("}","").replace("$","").replace("_","")
                 else:
                     label = str(label)

src/sage/dev/user_interface.py

@@ -23,6 +23,8 @@
 #                  http://www.gnu.org/licenses/
 #*****************************************************************************
 
+import six
+
 # log levels
 ERROR = -2
 WARNING = -1
@@ -180,7 +182,7 @@ def show(self, message, *args, **kwds):
             raise ValueError('the only allowed keyword argument is "log_level"')
         config_log_level = int(self._config.get("log_level", str(INFO)))
         if config_log_level >= log_level:
-            if isinstance(message, basestring):
+            if isinstance(message, six.string_types):
                 self._show(message, log_level, *args)
             else:
                 for msg in message:

src/sage/doctest/control.py

@@ -20,6 +20,7 @@
 #*****************************************************************************
 
 import random, os, sys, time, json, re, types
+import six
 import sage.misc.flatten
 from sage.structure.sage_object import SageObject
 from sage.env import DOT_SAGE, SAGE_LIB, SAGE_SRC
@@ -235,7 +236,7 @@ def __init__(self, options, args):
         if options.verbose:
             options.show_skipped = True
 
-        if isinstance(options.optional, basestring):
+        if isinstance(options.optional, six.string_types):
             s = options.optional.lower()
             if s in ['all', 'true']:
                 options.optional = True
@@ -1027,7 +1028,7 @@ def stringify(x):
                 return [base]
             else:
                 return [os.path.join(base, file) + ext]
-        elif isinstance(x, basestring):
+        elif isinstance(x, six.string_types):
             return [os.path.abspath(x)]
     F = stringify(module)
     if options is None:

src/sage/games/sudoku.py

@@ -21,6 +21,7 @@
 #                  http://www.gnu.org/licenses/
 ######################################################################
 
+import six
 from sage.structure.sage_object import SageObject
 
 def sudoku(m):
@@ -180,7 +181,7 @@ def __init__(self, puzzle, verify_input = True):
             if verify_input and not(puzzle.is_square()):
                 raise ValueError('Sudoku puzzle must be a square matrix')
             self.puzzle = tuple([int(x) for x in puzzle.list()])
-        elif isinstance(puzzle, basestring):
+        elif isinstance(puzzle, six.string_types):
             puzzle_size = int(round(sqrt(len(puzzle))))
             puzzle_numeric = []
             for char in puzzle:

src/sage/geometry/polyhedron/base.py

@@ -12,7 +12,7 @@
 #                  http://www.gnu.org/licenses/
 ########################################################################
 
-
+import six
 from sage.structure.element import Element, coerce_binop, is_Vector
 
 from sage.misc.all import cached_method, prod
@@ -646,7 +646,7 @@ def merge_options(*opts):
                     continue
                 elif opt is False:
                     return False
-                elif isinstance(opt, (basestring, list, tuple)):
+                elif isinstance(opt, (six.string_types, list, tuple)):
                     merged['color'] = opt
                 else:
                     merged.update(opt)

src/sage/groups/abelian_gps/abelian_group.py

@@ -201,7 +201,7 @@
 #                  http://www.gnu.org/licenses/
 ##########################################################################
 
-
+import six
 from sage.rings.integer import Integer
 from sage.rings.integer_ring import ZZ
 from sage.structure.unique_representation import UniqueRepresentation
@@ -536,7 +536,7 @@ def __init__(self, generator_orders, names):
             sage: A.category()
             Category of commutative groups
         """
-        assert isinstance(names, (basestring, tuple))
+        assert isinstance(names, (six.string_types, tuple))
         assert isinstance(generator_orders, tuple)
         assert all(isinstance(order,Integer) for order in generator_orders)
         self._gens_orders = generator_orders

src/sage/groups/braid.py

@@ -61,7 +61,7 @@
 #                  http://www.gnu.org/licenses/
 ##############################################################################
 
-
+import six
 from sage.rings.integer import Integer
 from sage.rings.integer_ring import IntegerRing
 from sage.misc.cachefunc import cached_method
@@ -1197,7 +1197,7 @@ def BraidGroup(n=None, names='s'):
             n = None
     # derive n from counting names
     if n is None:
-        if isinstance(names, basestring):
+        if isinstance(names, six.string_types):
             n = len(names.split(','))
         else:
             names = list(names)

src/sage/groups/free_group.py

@@ -60,7 +60,7 @@
 #                  http://www.gnu.org/licenses/
 ##############################################################################
 
-
+import six
 from sage.groups.group import Group
 from sage.groups.libgap_wrapper import ParentLibGAP, ElementLibGAP
 from sage.structure.unique_representation import UniqueRepresentation
@@ -622,7 +622,7 @@ def FreeGroup(n=None, names='x', index_set=None, abelian=False, **kwds):
             n = None
     # derive n from counting names
     if n is None:
-        if isinstance(names, basestring):
+        if isinstance(names, six.string_types):
             n = len(names.split(','))
         else:
             names = list(names)

src/sage/interfaces/expect.py

@@ -48,6 +48,7 @@
 import gc
 import quit
 import cleaner
+import six
 from random import randrange
 
 ########################################################
@@ -179,7 +180,7 @@ def __init__(self, name, prompt, command=None, server=None,
         self.__max_startup_time = max_startup_time
 
         #Handle the log file
-        if isinstance(logfile, basestring):
+        if isinstance(logfile, six.string_types):
             self.__logfile = None
             self.__logfilename = logfile
         else:
@@ -849,7 +850,7 @@ def _eval_line(self, line, allow_use_file=True, wait_for_prompt=True, restart_if
 
             if len(line)>0:
                 try:
-                    if isinstance(wait_for_prompt, basestring):
+                    if isinstance(wait_for_prompt, six.string_types):
                         E.expect(wait_for_prompt)
                     else:
                         E.expect(self._prompt)
@@ -1206,7 +1207,7 @@ def eval(self, code, strip=True, synchronize=False, locals=None, allow_use_file=
             except AttributeError:
                 pass
 
-        if not isinstance(code, basestring):
+        if not isinstance(code, six.string_types):
             raise TypeError('input code must be a string.')
 
         #Remove extra whitespace
@@ -1294,7 +1295,7 @@ def __init__(self, parent, value, is_name=False, name=None):
         # idea: Joe Wetherell -- try to find out if the output
         # is too long and if so get it using file, otherwise
         # don't.
-        if isinstance(value, basestring) and parent._eval_using_file_cutoff and \
+        if isinstance(value, six.string_types) and parent._eval_using_file_cutoff and \
            parent._eval_using_file_cutoff < len(value):
             self._get_using_file = True
 

src/sage/interfaces/interface.py

@@ -37,6 +37,7 @@
 #*****************************************************************************
 
 import operator
+import six
 
 from sage.structure.sage_object import SageObject
 from sage.structure.parent_base import ParentWithBase
@@ -166,7 +167,7 @@ def __call__(self, x, name=None):
             except (NotImplementedError, TypeError):
                 pass
 
-        if isinstance(x, basestring):
+        if isinstance(x, six.string_types):
             return cls(self, x, name=name)
         try:
             return self._coerce_from_special_method(x)

src/sage/interfaces/r.py

@@ -214,6 +214,7 @@
 from expect import Expect, ExpectElement, ExpectFunction, FunctionElement
 from sage.env import DOT_SAGE
 import re
+import six
 import sage.rings.integer
 from sage.structure.element import parent
 
@@ -1307,7 +1308,7 @@ def __getitem__(self, n):
             [1] 1 3
         """
         P = self._check_valid()
-        if isinstance(n, basestring):
+        if isinstance(n, six.string_types):
             n = n.replace('self', self._name)
             return P.new('%s[%s]'%(self._name, n))
         elif parent(n) is P:  # the key is RElement itself

src/sage/matrix/operation_table.py

@@ -10,6 +10,7 @@
 #                  http://www.gnu.org/licenses/
 #******************************************************************************
 
+import six
 from sage.structure.sage_object import SageObject
 
 class OperationTable(SageObject):
@@ -519,7 +520,7 @@ def _name_maker(self, names):
                 raise ValueError('list of element names must be the same size as the set, %s != %s'%(len(names), self._n))
             width = 0
             for str in names:
-                if not isinstance(str, basestring):
+                if not isinstance(str, six.string_types):
                     raise ValueError('list of element names must only contain strings, not %s'%str)
                 if len(str) > width:
                     width = len(str)
@@ -693,9 +694,9 @@ def set_print_symbols(self, ascii, latex):
             ...
             ValueError: ASCII symbol should be a single character, not 5
         """
-        if not isinstance(ascii, basestring) or not len(ascii)==1:
+        if not isinstance(ascii, six.string_types) or not len(ascii)==1:
             raise ValueError('ASCII symbol should be a single character, not %s' % ascii)
-        if not isinstance(latex, basestring):
+        if not isinstance(latex, six.string_types):
             raise ValueError('LaTeX symbol must be a string, not %s' % latex)
         self._ascii_symbol = ascii
         self._latex_symbol = latex

src/sage/misc/gperftools.py

@@ -204,11 +204,12 @@ def _pprof(self):
 
         EXAMPLES::
 
+            sage: import six
             sage: from sage.misc.gperftools import Profiler
             sage: prof = Profiler()
             sage: try:
             ....:     pp = prof._pprof()
-            ....:     assert isinstance(pp, basestring)
+            ....:     assert isinstance(pp, six.string_types)
             ....: except OSError:
             ....:     pass    # not installed
         """

src/sage/misc/sage_eval.py

@@ -10,6 +10,7 @@
 #                  http://www.gnu.org/licenses/
 #*****************************************************************************
 
+import six
 from copy import copy
 import sage.repl.preparse as preparser
 
@@ -177,7 +178,7 @@ def sage_eval(source, locals=None, cmds='', preparse=True):
             locals = copy(source[2])
         source = source[1]
 
-    if not isinstance(source, basestring):
+    if not isinstance(source, six.string_types):
         raise TypeError("source must be a string.")
 
     if locals is None: