Replace use of six.text_type with str

This removes the last use of the six package allowing Sphinx to remove
it as a dependency.

30 files changed, 108 insertions, 177 deletions

diff --git a/CHANGES b/CHANGES
index 3b9794c61..f58a03b56 100644
--- a/CHANGES
+++ b/CHANGES
@@ -17,6 +17,7 @@ Dependencies
   which in Ubuntu xenial are provided by package ``fonts-freefont-otf``, and
   e.g. in Fedora 29 via package ``texlive-gnu-freefont``.
 * requests 2.5.0 or above
+* The six package is no longer a dependency.
 
 Incompatible changes
 --------------------
diff --git a/setup.py b/setup.py
index 50c4b3f3a..6e28a10fc 100644
--- a/setup.py
+++ b/setup.py
@@ -15,7 +15,6 @@ if sys.version_info < (3, 5):
     sys.exit(1)
 
 install_requires = [
-    'six>=1.5',
     'Jinja2>=2.3',
     'Pygments>=2.0',
     'docutils>=0.12',
diff --git a/sphinx/builders/html.py b/sphinx/builders/html.py
index 41931af62..a8f578863 100644
--- a/sphinx/builders/html.py
+++ b/sphinx/builders/html.py
@@ -25,7 +25,6 @@ from docutils.frontend import OptionParser
 from docutils.io import DocTreeInput, StringOutput
 from docutils.readers.doctree import Reader as DoctreeReader
 from docutils.utils import relative_path
-from six import text_type
 
 from sphinx import package_dir, __display_version__
 from sphinx.application import ENV_PICKLE_FILENAME
@@ -86,10 +85,10 @@ def get_stable_hash(obj):
         return get_stable_hash(list(obj.items()))
     elif isinstance(obj, (list, tuple)):
         obj = sorted(get_stable_hash(o) for o in obj)
-    return md5(text_type(obj).encode()).hexdigest()
+    return md5(str(obj).encode()).hexdigest()
 
 
-class Stylesheet(text_type):
+class Stylesheet(str):
     """A metadata of stylesheet.
 
     To keep compatibility with old themes, an instance of stylesheet behaves as
@@ -101,7 +100,7 @@ class Stylesheet(text_type):
 
     def __new__(cls, filename, *args, **attributes):
         # type: (str, str, str) -> None
-        self = text_type.__new__(cls, filename)  # type: ignore
+        self = str.__new__(cls, filename)  # type: ignore
         self.filename = filename
         self.attributes = attributes
         self.attributes.setdefault('rel', 'stylesheet')
@@ -146,7 +145,7 @@ class JSContainer(list):
         return ret
 
 
-class JavaScript(text_type):
+class JavaScript(str):
     """A metadata of javascript file.
 
     To keep compatibility with old themes, an instance of javascript behaves as
@@ -158,7 +157,7 @@ class JavaScript(text_type):
 
     def __new__(cls, filename, **attributes):
         # type: (str, **str) -> None
-        self = text_type.__new__(cls, filename)  # type: ignore
+        self = str.__new__(cls, filename)  # type: ignore
         self.filename = filename
         self.attributes = attributes
         self.attributes.setdefault('type', 'text/javascript')
diff --git a/sphinx/builders/latex/__init__.py b/sphinx/builders/latex/__init__.py
index 64f1bf29d..edb50a4a3 100644
--- a/sphinx/builders/latex/__init__.py
+++ b/sphinx/builders/latex/__init__.py
@@ -12,7 +12,6 @@ import os
 from os import path
 
 from docutils.frontend import OptionParser
-from six import text_type
 
 from sphinx import package_dir, addnodes, highlighting
 from sphinx.builders import Builder
@@ -24,7 +23,7 @@ from sphinx.builders.latex.transforms import (
 from sphinx.config import ENUM
 from sphinx.environment import NoUri
 from sphinx.environment.adapters.asset import ImageAdapter
-from sphinx.errors import SphinxError, ConfigError
+from sphinx.errors import SphinxError
 from sphinx.locale import _, __
 from sphinx.transforms import SphinxTransformer
 from sphinx.util import texescape, logging, status_iterator
@@ -400,23 +399,6 @@ class LaTeXBuilder(Builder):
 
 def validate_config_values(app, config):
     # type: (Sphinx, Config) -> None
-    for document in config.latex_documents:
-        try:
-            text_type(document[2])
-        except UnicodeDecodeError:
-            raise ConfigError(
-                __('Invalid latex_documents.title found (might contain non-ASCII chars. '
-                   'Please use u"..." notation instead): %r') % (document,)
-            )
-
-        try:
-            text_type(document[3])
-        except UnicodeDecodeError:
-            raise ConfigError(
-                __('Invalid latex_documents.author found (might contain non-ASCII chars. '
-                   'Please use u"..." notation instead): %r') % (document,)
-            )
-
     for key in list(config.latex_elements):
         if key not in DEFAULT_SETTINGS:
             msg = __("Unknown configure key: latex_elements[%r]. ignored.")
diff --git a/sphinx/cmd/build.py b/sphinx/cmd/build.py
index f2efa9638..15c6827ff 100644
--- a/sphinx/cmd/build.py
+++ b/sphinx/cmd/build.py
@@ -16,7 +16,6 @@ import sys
 import traceback
 
 from docutils.utils import SystemMessage
-from six import text_type
 
 import sphinx.locale
 from sphinx import __display_version__, package_dir
@@ -53,17 +52,17 @@ def handle_exception(app, args, exception, stderr=sys.stderr):
             print(terminal_safe(exception.args[0]), file=stderr)
         elif isinstance(exception, SphinxError):
             print(red('%s:' % exception.category), file=stderr)
-            print(terminal_safe(text_type(exception)), file=stderr)
+            print(terminal_safe(str(exception)), file=stderr)
         elif isinstance(exception, UnicodeError):
             print(red(__('Encoding error:')), file=stderr)
-            print(terminal_safe(text_type(exception)), file=stderr)
+            print(terminal_safe(str(exception)), file=stderr)
             tbpath = save_traceback(app)
             print(red(__('The full traceback has been saved in %s, if you want '
                          'to report the issue to the developers.') % tbpath),
                   file=stderr)
         elif isinstance(exception, RuntimeError) and 'recursion depth' in str(exception):
             print(red(__('Recursion error:')), file=stderr)
-            print(terminal_safe(text_type(exception)), file=stderr)
+            print(terminal_safe(str(exception)), file=stderr)
             print(file=stderr)
             print(__('This can happen with very large or deeply nested source '
                      'files.  You can carefully increase the default Python '
diff --git a/sphinx/cmd/quickstart.py b/sphinx/cmd/quickstart.py
index b3db8900e..d3e41aa54 100644
--- a/sphinx/cmd/quickstart.py
+++ b/sphinx/cmd/quickstart.py
@@ -32,7 +32,6 @@ except ImportError:
     USE_LIBEDIT = False
 
 from docutils.utils import column_width
-from six import text_type
 
 import sphinx.locale
 from sphinx import __display_version__, package_dir
@@ -158,7 +157,7 @@ def term_decode(text):
     warnings.warn('term_decode() is deprecated.',
                   RemovedInSphinx40Warning, stacklevel=2)
 
-    if isinstance(text, text_type):
+    if isinstance(text, str):
         return text
 
     # Use the known encoding, if possible
@@ -391,10 +390,9 @@ def generate(d, overwrite=True, silent=False, templatedir=None):
     d['project_underline'] = column_width(d['project']) * '='
     d.setdefault('extensions', [])
     d['copyright'] = time.strftime('%Y') + ', ' + d['author']
-    d['author_texescaped'] = text_type(d['author']).\
-        translate(texescape.tex_escape_map)
+    d['author_texescaped'] = d['author'].translate(texescape.tex_escape_map)
     d['project_doc'] = d['project'] + ' Documentation'
-    d['project_doc_texescaped'] = text_type(d['project'] + ' Documentation').\
+    d['project_doc_texescaped'] = (d['project'] + ' Documentation').\
         translate(texescape.tex_escape_map)
 
     # escape backslashes and single quotes in strings that are put into
diff --git a/sphinx/config.py b/sphinx/config.py
index 002b2a559..338de770c 100644
--- a/sphinx/config.py
+++ b/sphinx/config.py
@@ -16,8 +16,6 @@ from collections import OrderedDict
 from os import path, getenv
 from typing import Any, NamedTuple, Union
 
-from six import text_type
-
 from sphinx.deprecation import RemovedInSphinx30Warning, RemovedInSphinx40Warning
 from sphinx.errors import ConfigError, ExtensionError
 from sphinx.locale import _, __
@@ -41,7 +39,7 @@ copyright_year_re = re.compile(r'^((\d{4}-)?)(\d{4})(?=[ ,])')
 
 ConfigValue = NamedTuple('ConfigValue', [('name', str),
                                          ('value', Any),
-                                         ('rebuild', Union[bool, text_type])])
+                                         ('rebuild', Union[bool, str])])
 
 
 def is_serializable(obj):
@@ -78,7 +76,7 @@ class ENUM:
 
 
 # RemovedInSphinx40Warning
-string_classes = [text_type]  # type: List
+string_classes = [str]  # type: List
 
 
 class Config:
diff --git a/sphinx/domains/cpp.py b/sphinx/domains/cpp.py
index 1550154d3..b8a7da02f 100644
--- a/sphinx/domains/cpp.py
+++ b/sphinx/domains/cpp.py
@@ -13,7 +13,6 @@ from copy import deepcopy
 
 from docutils import nodes, utils
 from docutils.parsers.rst import directives
-from six import text_type
 
 from sphinx import addnodes
 from sphinx.directives import ObjectDescription
@@ -633,7 +632,7 @@ class ASTBase:
 
     def __str__(self):
         # type: () -> str
-        return self._stringify(lambda ast: text_type(ast))
+        return self._stringify(lambda ast: str(ast))
 
     def get_display_string(self):
         # type: () -> str
@@ -664,7 +663,7 @@ class ASTCPPAttribute(ASTBase):
 
     def describe_signature(self, signode):
         # type: (addnodes.desc_signature) -> None
-        txt = text_type(self)
+        txt = str(self)
         signode.append(nodes.Text(txt, txt))
 
 
@@ -703,7 +702,7 @@ class ASTGnuAttributeList(ASTBase):
 
     def describe_signature(self, signode):
         # type: (addnodes.desc_signature) -> None
-        txt = text_type(self)
+        txt = str(self)
         signode.append(nodes.Text(txt, txt))
 
 
@@ -737,7 +736,7 @@ class ASTParenAttribute(ASTBase):
 
     def describe_signature(self, signode):
         # type: (addnodes.desc_signature) -> None
-        txt = text_type(self)
+        txt = str(self)
         signode.append(nodes.Text(txt, txt))
 
 
@@ -777,7 +776,7 @@ class ASTBooleanLiteral(ASTBase):
             return 'L0E'
 
     def describe_signature(self, signode, mode, env, symbol):
-        signode.append(nodes.Text(text_type(self)))
+        signode.append(nodes.Text(str(self)))
 
 
 class ASTNumberLiteral(ASTBase):
@@ -794,7 +793,7 @@ class ASTNumberLiteral(ASTBase):
         return "L%sE" % self.data
 
     def describe_signature(self, signode, mode, env, symbol):
-        txt = text_type(self)
+        txt = str(self)
         signode.append(nodes.Text(txt, txt))
 
 
@@ -828,7 +827,7 @@ class ASTCharLiteral(ASTBase):
         return self.type + str(self.value)
 
     def describe_signature(self, signode, mode, env, symbol):
-        txt = text_type(self)
+        txt = str(self)
         signode.append(nodes.Text(txt, txt))
 
 
@@ -847,7 +846,7 @@ class ASTStringLiteral(ASTBase):
         return "LA%d_KcE" % (len(self.data) - 2)
 
     def describe_signature(self, signode, mode, env, symbol):
-        txt = text_type(self)
+        txt = str(self)
         signode.append(nodes.Text(txt, txt))
 
 
@@ -910,7 +909,7 @@ class ASTFoldExpr(ASTBase):
         # type: (int) -> str
         assert version >= 3
         if version == 3:
-            return text_type(self)
+            return str(self)
         # TODO: find the right mangling scheme
         assert False
 
@@ -1466,7 +1465,7 @@ class ASTFallbackExpr(ASTBase):
 
     def get_id(self, version):
         # type: (int) -> str
-        return text_type(self.expr)
+        return str(self.expr)
 
     def describe_signature(self, signode, mode, env, symbol):
         signode += nodes.Text(self.expr)
@@ -1504,7 +1503,7 @@ class ASTIdentifier(ASTBase):
             if self.is_anon():
                 return 'Ut%d_%s' % (len(self.identifier) - 1, self.identifier[1:])
             else:
-                return text_type(len(self.identifier)) + self.identifier
+                return str(len(self.identifier)) + self.identifier
 
     # and this is where we finally make a difference between __str__ and the display string
 
@@ -1987,7 +1986,7 @@ class ASTOperator(ASTBase):
     def describe_signature(self, signode, mode, env, prefix, templateArgs, symbol):
         # type: (addnodes.desc_signature, str, Any, str, str, Symbol) -> None
         _verify_description_mode(mode)
-        identifier = text_type(self)
+        identifier = str(self)
         if mode == 'lastIsName':
             signode += addnodes.desc_name(identifier, identifier)
         else:
@@ -2036,7 +2035,7 @@ class ASTOperatorType(ASTOperator):
 
     def get_name_no_template(self):
         # type: () -> str
-        return text_type(self)
+        return str(self)
 
 
 class ASTOperatorLiteral(ASTOperator):
@@ -2071,9 +2070,9 @@ class ASTTemplateArgConstant(ASTBase):
     def get_id(self, version):
         # type: (int) -> str
         if version == 1:
-            return text_type(self).replace(' ', '-')
+            return str(self).replace(' ', '-')
         if version == 2:
-            return 'X' + text_type(self) + 'E'
+            return 'X' + str(self) + 'E'
         return 'X' + self.value.get_id(version) + 'E'
 
     def describe_signature(self, signode, mode, env, symbol):
@@ -2148,7 +2147,7 @@ class ASTNestedNameElement(ASTBase):
 
     def describe_signature(self, signode, mode, env, prefix, symbol):
         # type: (addnodes.desc_signature, str, BuildEnvironment, str, Symbol) -> None
-        tArgs = text_type(self.templateArgs) if self.templateArgs is not None else ''
+        tArgs = str(self.templateArgs) if self.templateArgs is not None else ''
         self.identOrOp.describe_signature(signode, mode, env, prefix, tArgs, symbol)
         if self.templateArgs is not None:
             self.templateArgs.describe_signature(signode, mode, env, symbol)
@@ -2181,7 +2180,7 @@ class ASTNestedName(ASTBase):
     def get_id(self, version, modifiers=''):
         # type: (int, str) -> str
         if version == 1:
-            tt = text_type(self)
+            tt = str(self)
             if tt in _id_shorthands_v1:
                 return _id_shorthands_v1[tt]
             else:
@@ -2216,9 +2215,9 @@ class ASTNestedName(ASTBase):
         _verify_description_mode(mode)
         # just print the name part, with template args, not template params
         if mode == 'noneIsName':
-            signode += nodes.Text(text_type(self))
+            signode += nodes.Text(str(self))
         elif mode == 'param':
-            name = text_type(self)
+            name = str(self)
             signode += nodes.emphasis(name, name)
         elif mode == 'markType' or mode == 'lastIsName':
             # Each element should be a pending xref targeting the complete
@@ -2251,10 +2250,10 @@ class ASTNestedName(ASTBase):
                 if template:
                     dest += nodes.Text("template ")
                 first = False
-                txt_nne = text_type(nne)
+                txt_nne = str(nne)
                 if txt_nne != '':
                     if nne.templateArgs and iTemplateParams < len(templateParams):
-                        templateParamsPrefix += text_type(templateParams[iTemplateParams])
+                        templateParamsPrefix += str(templateParams[iTemplateParams])
                         iTemplateParams += 1
                     nne.describe_signature(dest, 'markType',
                                            env, templateParamsPrefix + prefix, symbol)
@@ -2299,7 +2298,7 @@ class ASTTrailingTypeSpecFundamental(ASTBase):
 
     def describe_signature(self, signode, mode, env, symbol):
         # type: (addnodes.desc_signature, str, BuildEnvironment, Symbol) -> None
-        signode += nodes.Text(text_type(self.name))
+        signode += nodes.Text(str(self.name))
 
 
 class ASTTrailingTypeSpecName(ASTBase):
@@ -2347,7 +2346,7 @@ class ASTTrailingTypeSpecDecltypeAuto(ASTBase):
 
     def describe_signature(self, signode, mode, env, symbol):
         # type: (addnodes.desc_signature, str, BuildEnvironment, Symbol) -> None
-        signode.append(nodes.Text(text_type(self)))
+        signode.append(nodes.Text(str(self)))
 
 
 class ASTTrailingTypeSpecDecltype(ASTBase):
@@ -2460,7 +2459,7 @@ class ASTParametersQualifiers(ASTBase):
             if not first:
                 res.append(', ')
             first = False
-            res.append(text_type(a))
+            res.append(str(a))
         res.append(')')
         if self.volatile:
             res.append(' volatile')
@@ -2471,7 +2470,7 @@ class ASTParametersQualifiers(ASTBase):
             res.append(self.refQual)
         if self.exceptionSpec:
             res.append(' ')
-            res.append(text_type(self.exceptionSpec))
+            res.append(str(self.exceptionSpec))
         if self.final:
             res.append(' final')
         if self.override:
@@ -2508,13 +2507,13 @@ class ASTParametersQualifiers(ASTBase):
         if self.refQual:
             _add_text(signode, self.refQual)
         if self.exceptionSpec:
-            _add_anno(signode, text_type(self.exceptionSpec))
+            _add_anno(signode, str(self.exceptionSpec))
         if self.final:
             _add_anno(signode, 'final')
         if self.override:
             _add_anno(signode, 'override')
         if self.initializer:
-            _add_text(signode, '= ' + text_type(self.initializer))
+            _add_text(signode, '= ' + str(self.initializer))
 
 
 class ASTDeclSpecsSimple(ASTBase):
@@ -2646,7 +2645,7 @@ class ASTDeclSpecs(ASTBase):
             if len(res) > 0:
                 res.append(" ")
             res.append(transform(self.trailingTypeSpec))
-            r = text_type(self.rightSpecs)
+            r = str(self.rightSpecs)
             if len(r) > 0:
                 if len(res) > 0:
                     res.append(" ")
@@ -2697,7 +2696,7 @@ class ASTArray(ASTBase):
             return 'A'
         if version == 2:
             if self.size:
-                return 'A' + text_type(self.size) + '_'
+                return 'A' + str(self.size) + '_'
             else:
                 return 'A_'
         if self.size:
@@ -3314,7 +3313,7 @@ class ASTType(ASTBase):
         _verify_description_mode(mode)
         self.declSpecs.describe_signature(signode, 'markType', env, symbol)
         if (self.decl.require_space_after_declSpecs() and
-                len(text_type(self.declSpecs)) > 0):
+                len(str(self.declSpecs)) > 0):
             signode += nodes.Text(' ')
         # for parameters that don't really declare new names we get 'markType',
         # this should not be propagated, but be 'noneIsName'.
@@ -3922,8 +3921,8 @@ class Symbol:
                 param = templateParams.params[i]
                 arg = templateArgs.args[i]
                 # TODO: doing this by string manipulation is probably not the most efficient
-                paramName = text_type(param.name)
-                argTxt = text_type(arg)
+                paramName = str(param.name)
+                argTxt = str(arg)
                 isArgPackExpansion = argTxt.endswith('...')
                 if param.isPack != isArgPackExpansion:
                     return True
@@ -3951,13 +3950,13 @@ class Symbol:
                     return False
             if templateParams:
                 # TODO: do better comparison
-                if text_type(s.templateParams) != text_type(templateParams):
+                if str(s.templateParams) != str(templateParams):
                     return False
             if (s.templateArgs is None) != (templateArgs is None):
                 return False
             if s.templateArgs:
                 # TODO: do better comparison
-                if text_type(s.templateArgs) != text_type(templateArgs):
+                if str(s.templateArgs) != str(templateArgs):
                     return False
             return True
         if matchSelf and matches(self):
@@ -4246,7 +4245,7 @@ class Symbol:
                 if not ourChild.declaration:
                     ourChild._fill_empty(otherChild.declaration, otherChild.docname)
                 elif ourChild.docname != otherChild.docname:
-                    name = text_type(ourChild.declaration)
+                    name = str(ourChild.declaration)
                     msg = __("Duplicate declaration, also defined in '%s'.\n"
                              "Declaration is '%s'.")
                     msg = msg % (ourChild.docname, name)
@@ -4394,20 +4393,20 @@ class Symbol:
             res.append('::')
         else:
             if self.templateParams:
-                res.append(text_type(self.templateParams))
+                res.append(str(self.templateParams))
                 res.append('\n')
                 res.append('\t' * indent)
             if self.identOrOp:
-                res.append(text_type(self.identOrOp))
+                res.append(str(self.identOrOp))
             else:
-                res.append(text_type(self.declaration))
+                res.append(str(self.declaration))
             if self.templateArgs:
-                res.append(text_type(self.templateArgs))
+                res.append(str(self.templateArgs))
             if self.declaration:
                 res.append(": ")
                 if self.isRedeclaration:
                     res.append('!!duplicate!! ')
-                res.append(text_type(self.declaration))
+                res.append(str(self.declaration))
         if self.docname:
             res.append('\t(')
             res.append(self.docname)
@@ -6144,7 +6143,7 @@ class DefinitionParser:
                 msg += " Declaration:\n\t"
                 if templatePrefix:
                     msg += "%s\n\t" % templatePrefix
-                msg += text_type(nestedName)
+                msg += str(nestedName)
                 self.warn(msg)
 
             newTemplates = []
@@ -6438,7 +6437,7 @@ class CPPObject(ObjectDescription):
         parentDecl = parentSymbol.declaration
         if parentDecl is not None and parentDecl.objectType == 'function':
             self.warn("C++ declarations inside functions are not supported." +
-                      " Parent function is " + text_type(parentSymbol.get_full_nested_name()))
+                      " Parent function is " + str(parentSymbol.get_full_nested_name()))
             name = _make_phony_error_name()
             symbol = parentSymbol.add_name(name)
             env.temp_data['cpp:last_symbol'] = symbol
@@ -6742,8 +6741,7 @@ class CPPExprRole:
         try:
             ast = parser.parse_expression()
         except DefinitionError as ex:
-            Warner().warn('Unparseable C++ expression: %r\n%s'
-                          % (text, text_type(ex.description)))
+            Warner().warn('Unparseable C++ expression: %r\n%s' % (text, ex))
             # see below
             return [self.node_type(text, text, classes=classes)], []
         parentSymbol = env.temp_data.get('cpp:parent_symbol', None)
@@ -6891,8 +6889,7 @@ class CPPDomain(Domain):
                 # strange, that we don't get the error now, use the original
                 return target, e
             t, ex = findWarning(e)
-            warner.warn('Unparseable C++ cross-reference: %r\n%s'
-                        % (t, text_type(ex.description)))
+            warner.warn('Unparseable C++ cross-reference: %r\n%s' % (t, ex))
             return None, None
         parentKey = node.get("cpp:parent_key", None)
         rootSymbol = self.data['root_symbol']
@@ -6923,7 +6920,7 @@ class CPPDomain(Domain):
                                               templateShorthand=True,
                                               matchSelf=True, recurseInAnon=True)
         if s is None or s.declaration is None:
-            txtName = text_type(name)
+            txtName = str(name)
             if txtName.startswith('std::') or txtName == 'std':
                 raise NoUri()
             return None, None
@@ -7026,7 +7023,7 @@ class CPPDomain(Domain):
                 continue
             assert symbol.docname
             fullNestedName = symbol.get_full_nested_name()
-            name = text_type(fullNestedName).lstrip(':')
+            name = str(fullNestedName).lstrip(':')
             dispname = fullNestedName.get_display_string().lstrip(':')
             objectType = symbol.declaration.objectType
             docname = symbol.docname
@@ -7045,7 +7042,7 @@ class CPPDomain(Domain):
         rootSymbol = self.data['root_symbol']
         parentSymbol = rootSymbol.direct_lookup(parentKey)
         parentName = parentSymbol.get_full_nested_name()
-        return '::'.join([text_type(parentName), target])
+        return '::'.join([str(parentName), target])
 
 
 def setup(app):
diff --git a/sphinx/environment/adapters/indexentries.py b/sphinx/environment/adapters/indexentries.py
index 772a72715..4ca1c71f6 100644
--- a/sphinx/environment/adapters/indexentries.py
+++ b/sphinx/environment/adapters/indexentries.py
@@ -12,8 +12,6 @@ import re
 import unicodedata
 from itertools import groupby
 
-from six import text_type
-
 from sphinx.locale import _, __
 from sphinx.util import split_into, logging
 
@@ -44,7 +42,7 @@ class IndexEntries:
             # Force the word to be unicode if it's a ASCII bytestring.
             # This will solve problems with unicode normalization later.
             # For instance the RFC role will add bytestrings at the moment
-            word = text_type(word)
+            word = str(word)
             entry = dic.get(word)
             if not entry:
                 dic[word] = entry = [[], {}, key]
diff --git a/sphinx/environment/collectors/indexentries.py b/sphinx/environment/collectors/indexentries.py
index 5ab309407..27d2c771b 100644
--- a/sphinx/environment/collectors/indexentries.py
+++ b/sphinx/environment/collectors/indexentries.py
@@ -8,8 +8,6 @@
     :license: BSD, see LICENSE for details.
 """
 
-from six import text_type
-
 from sphinx import addnodes
 from sphinx.environment.collectors import EnvironmentCollector
 from sphinx.util import split_index_msg, logging
@@ -45,7 +43,7 @@ class IndexEntriesCollector(EnvironmentCollector):
                 for entry in node['entries']:
                     split_index_msg(entry[0], entry[1])
             except ValueError as exc:
-                logger.warning(text_type(exc), location=node)
+                logger.warning(str(exc), location=node)
                 node.parent.remove(node)
             else:
                 for entry in node['entries']:
diff --git a/sphinx/ext/autodoc/__init__.py b/sphinx/ext/autodoc/__init__.py
index 900f4a378..ebd3a37b7 100644
--- a/sphinx/ext/autodoc/__init__.py
+++ b/sphinx/ext/autodoc/__init__.py
@@ -12,12 +12,10 @@
 
 import inspect
 import re
-import sys
 import warnings
 from typing import Any
 
 from docutils.statemachine import StringList
-from six import text_type
 
 import sphinx
 from sphinx.deprecation import RemovedInSphinx30Warning, RemovedInSphinx40Warning
@@ -461,13 +459,7 @@ class Documenter:
     def get_sourcename(self):
         # type: () -> str
         if self.analyzer:
-            # prevent encoding errors when the file name is non-ASCII
-            if not isinstance(self.analyzer.srcname, text_type):
-                filename = text_type(self.analyzer.srcname,
-                                     sys.getfilesystemencoding(), 'replace')
-            else:
-                filename = self.analyzer.srcname
-            return '%s:docstring of %s' % (filename, self.fullname)
+            return '%s:docstring of %s' % (self.analyzer.srcname, self.fullname)
         return 'docstring of %s' % self.fullname
 
     def add_content(self, more_content, no_docstring=False):
diff --git a/sphinx/ext/autosummary/__init__.py b/sphinx/ext/autosummary/__init__.py
index b0ffe093c..45e66e911 100644
--- a/sphinx/ext/autosummary/__init__.py
+++ b/sphinx/ext/autosummary/__init__.py
@@ -65,7 +65,6 @@ from docutils import nodes
 from docutils.parsers.rst import directives
 from docutils.parsers.rst.states import RSTStateMachine, state_classes
 from docutils.statemachine import StringList
-from six import text_type
 
 import sphinx
 from sphinx import addnodes
@@ -160,8 +159,7 @@ def autosummary_table_visit_html(self, node):
             par = cast(nodes.paragraph, col1_entry[0])
             for j, subnode in enumerate(list(par)):
                 if isinstance(subnode, nodes.Text):
-                    new_text = text_type(subnode.astext())
-                    new_text = new_text.replace(" ", "\u00a0")
+                    new_text = subnode.astext().replace(" ", "\u00a0")
                     par[j] = nodes.Text(new_text)
     except IndexError:
         pass
diff --git a/sphinx/ext/imgmath.py b/sphinx/ext/imgmath.py
index d93d3fb50..377da12f1 100644
--- a/sphinx/ext/imgmath.py
+++ b/sphinx/ext/imgmath.py
@@ -17,7 +17,6 @@ from os import path
 from subprocess import Popen, PIPE
 
 from docutils import nodes
-from six import text_type
 
 import sphinx
 from sphinx.errors import SphinxError
@@ -290,7 +289,7 @@ def html_visit_math(self, node):
     try:
         fname, depth = render_math(self, '$' + node.astext() + '$')
     except MathExtError as exc:
-        msg = text_type(exc)
+        msg = str(exc)
         sm = nodes.system_message(msg, type='WARNING', level=2,
                                   backrefs=[], source=node.astext())
         sm.walkabout(self)
@@ -317,7 +316,7 @@ def html_visit_displaymath(self, node):
     try:
         fname, depth = render_math(self, latex)
     except MathExtError as exc:
-        msg = text_type(exc)
+        msg = str(exc)
         sm = nodes.system_message(msg, type='WARNING', level=2,
                                   backrefs=[], source=node.astext())
         sm.walkabout(self)
diff --git a/sphinx/highlighting.py b/sphinx/highlighting.py
index 12fec930e..5fac63963 100644
--- a/sphinx/highlighting.py
+++ b/sphinx/highlighting.py
@@ -20,7 +20,6 @@ from pygments.lexers import PythonLexer, Python3Lexer, PythonConsoleLexer, \
     CLexer, TextLexer, RstLexer
 from pygments.styles import get_style_by_name
 from pygments.util import ClassNotFound
-from six import text_type
 
 from sphinx.deprecation import RemovedInSphinx30Warning
 from sphinx.ext import doctest
@@ -113,7 +112,7 @@ class PygmentsBridge:
 
     def highlight_block(self, source, lang, opts=None, location=None, force=False, **kwargs):
         # type: (str, str, Any, Any, bool, Any) -> str
-        if not isinstance(source, text_type):
+        if not isinstance(source, str):
             source = source.decode()
 
         # find out which lexer to use
diff --git a/sphinx/locale/__init__.py b/sphinx/locale/__init__.py
index 8d4058972..79d601460 100644
--- a/sphinx/locale/__init__.py
+++ b/sphinx/locale/__init__.py
@@ -14,8 +14,6 @@ import warnings
 from collections import UserString, defaultdict
 from gettext import NullTranslations
 
-from six import text_type
-
 from sphinx.deprecation import RemovedInSphinx30Warning
 
 if False:
@@ -41,7 +39,7 @@ class _TranslationProxy(UserString):
         # type: (Callable, str) -> object
         if not args:
             # not called with "function" and "arguments", but a plain string
-            return text_type(func)
+            return str(func)
         return object.__new__(cls)
 
     def __getnewargs__(self):
@@ -73,7 +71,7 @@ class _TranslationProxy(UserString):
 
     def __dir__(self):
         # type: () -> List[str]
-        return dir(text_type)
+        return dir(str)
 
     def __str__(self):
         # type: () -> str
@@ -124,7 +122,7 @@ class _TranslationProxy(UserString):
     def __repr__(self):
         # type: () -> str
         try:
-            return 'i' + repr(text_type(self.data))
+            return 'i' + repr(str(self.data))
         except Exception:
             return '<%s broken>' % self.__class__.__name__
 
diff --git a/sphinx/pycode/parser.py b/sphinx/pycode/parser.py
index ec04aecab..8aa2815d0 100644
--- a/sphinx/pycode/parser.py
+++ b/sphinx/pycode/parser.py
@@ -16,8 +16,6 @@ import tokenize
 from token import NAME, NEWLINE, INDENT, DEDENT, NUMBER, OP, STRING
 from tokenize import COMMENT, NL
 
-from six import text_type
-
 if False:
     # For type annotation
     from typing import Any, Dict, IO, List, Tuple  # NOQA
@@ -349,7 +347,7 @@ class VariableCommentPicker(ast.NodeVisitor):
                 targets = get_assign_targets(self.previous)
                 varnames = get_lvar_names(targets[0], self.get_self())
                 for varname in varnames:
-                    if isinstance(node.value.s, text_type):
+                    if isinstance(node.value.s, str):
                         docstring = node.value.s
                     else:
                         docstring = node.value.s.decode(self.encoding or 'utf-8')
diff --git a/sphinx/search/__init__.py b/sphinx/search/__init__.py
index 2fd43ca4f..6100fc453 100644
--- a/sphinx/search/__init__.py
+++ b/sphinx/search/__init__.py
@@ -13,8 +13,6 @@ import re
 import warnings
 from os import path
 
-from six import text_type
-
 from docutils import nodes
 
 from sphinx import addnodes
@@ -351,9 +349,9 @@ class IndexBuilder:
                     otypes[domainname, type] = typeindex
                     otype = domain.object_types.get(type)
                     if otype:
-                        # use unicode() to fire translation proxies
+                        # use str() to fire translation proxies
                         onames[typeindex] = (domainname, type,
-                                             text_type(domain.get_type_name(otype)))
+                                             str(domain.get_type_name(otype)))
                     else:
                         onames[typeindex] = (domainname, type, type)
                 if anchor == fullname:
diff --git a/sphinx/testing/path.py b/sphinx/testing/path.py
index d80bb0786..9477391b4 100644
--- a/sphinx/testing/path.py
+++ b/sphinx/testing/path.py
@@ -9,8 +9,6 @@ import os
 import shutil
 import sys
 
-from six import text_type
-
 if False:
     # For type annotation
     import builtins  # NOQA
@@ -20,7 +18,7 @@ if False:
 FILESYSTEMENCODING = sys.getfilesystemencoding() or sys.getdefaultencoding()
 
 
-class path(text_type):
+class path(str):
     """
     Represents a path which behaves like a string.
     """
@@ -222,4 +220,4 @@ class path(text_type):
 
     def __repr__(self):
         # type: () -> str
-        return '%s(%s)' % (self.__class__.__name__, text_type.__repr__(self))
+        return '%s(%s)' % (self.__class__.__name__, super().__repr__())
diff --git a/sphinx/transforms/post_transforms/code.py b/sphinx/transforms/post_transforms/code.py
index a732842c2..610437ac6 100644
--- a/sphinx/transforms/post_transforms/code.py
+++ b/sphinx/transforms/post_transforms/code.py
@@ -13,7 +13,6 @@ from typing import NamedTuple
 
 from docutils import nodes
 from pygments.lexers import PythonConsoleLexer, guess_lexer
-from six import text_type
 
 from sphinx import addnodes
 from sphinx.ext import doctest
@@ -25,7 +24,7 @@ if False:
     from sphinx.application import Sphinx  # NOQA
 
 
-HighlightSetting = NamedTuple('HighlightSetting', [('language', text_type),
+HighlightSetting = NamedTuple('HighlightSetting', [('language', str),
                                                    ('lineno_threshold', int)])
 
 
diff --git a/sphinx/transforms/post_transforms/images.py b/sphinx/transforms/post_transforms/images.py
index 8f63dbda5..a863a00fa 100644
--- a/sphinx/transforms/post_transforms/images.py
+++ b/sphinx/transforms/post_transforms/images.py
@@ -13,7 +13,6 @@ from hashlib import sha1
 from math import ceil
 
 from docutils import nodes
-from six import text_type
 
 from sphinx.locale import __
 from sphinx.transforms import SphinxTransform
@@ -118,8 +117,7 @@ class ImageDownloader(BaseImageConverter):
                 node['uri'] = path
                 self.app.env.images.add_file(self.env.docname, path)
         except Exception as exc:
-            logger.warning(__('Could not fetch remote image: %s [%s]') %
-                           (node['uri'], text_type(exc)))
+            logger.warning(__('Could not fetch remote image: %s [%s]') % (node['uri'], exc))
 
 
 class DataURIExtractor(BaseImageConverter):
diff --git a/sphinx/util/__init__.py b/sphinx/util/__init__.py
index 11a2a9327..fbe6609e6 100644
--- a/sphinx/util/__init__.py
+++ b/sphinx/util/__init__.py
@@ -26,7 +26,6 @@ from time import mktime, strptime
 from urllib.parse import urlsplit, urlunsplit, quote_plus, parse_qsl, urlencode
 
 from docutils.utils import relative_path
-from six import text_type
 
 from sphinx.deprecation import RemovedInSphinx30Warning, RemovedInSphinx40Warning
 from sphinx.errors import PycodeError, SphinxParallelError, ExtensionError
@@ -70,9 +69,7 @@ def path_stabilize(filepath):
     # type: (str) -> str
     "normalize path separater and unicode string"
     newpath = filepath.replace(os.path.sep, SEP)
-    if isinstance(newpath, text_type):
-        newpath = unicodedata.normalize('NFC', newpath)
-    return newpath
+    return unicodedata.normalize('NFC', newpath)
 
 
 def get_matching_files(dirname, exclude_matchers=()):
@@ -637,9 +634,9 @@ def display_chunk(chunk):
     # type: (Any) -> str
     if isinstance(chunk, (list, tuple)):
         if len(chunk) == 1:
-            return text_type(chunk[0])
+            return str(chunk[0])
         return '%s .. %s' % (chunk[0], chunk[-1])
-    return text_type(chunk)
+    return str(chunk)
 
 
 def old_status_iterator(iterable, summary, color="darkgreen", stringify_func=display_chunk):
diff --git a/sphinx/util/images.py b/sphinx/util/images.py
index c74394c81..eaa188496 100644
--- a/sphinx/util/images.py
+++ b/sphinx/util/images.py
@@ -17,7 +17,6 @@ from os import path
 from typing import NamedTuple
 
 import imagesize
-from six import text_type
 
 from sphinx.deprecation import RemovedInSphinx30Warning
 
@@ -42,8 +41,8 @@ mime_suffixes = OrderedDict([
     ('.svgz', 'image/svg+xml'),
 ])
 
-DataURI = NamedTuple('DataURI', [('mimetype', text_type),
-                                 ('charset', text_type),
+DataURI = NamedTuple('DataURI', [('mimetype', str),
+                                 ('charset', str),
                                  ('data', bytes)])
 
 
diff --git a/sphinx/util/jsonimpl.py b/sphinx/util/jsonimpl.py
index eb4117f90..8054be0d7 100644
--- a/sphinx/util/jsonimpl.py
+++ b/sphinx/util/jsonimpl.py
@@ -11,8 +11,6 @@
 import json
 from collections import UserString
 
-from six import text_type
-
 if False:
     # For type annotation
     from typing import Any, IO  # NOQA
@@ -23,7 +21,7 @@ class SphinxJSONEncoder(json.JSONEncoder):
     def default(self, obj):
         # type: (Any) -> str
         if isinstance(obj, UserString):
-            return text_type(obj)
+            return str(obj)
         return super().default(obj)
 
 
diff --git a/sphinx/util/nodes.py b/sphinx/util/nodes.py
index e95313745..ddf78185e 100644
--- a/sphinx/util/nodes.py
+++ b/sphinx/util/nodes.py
@@ -12,7 +12,6 @@ import re
 from typing import Any, cast
 
 from docutils import nodes
-from six import text_type
 
 from sphinx import addnodes
 from sphinx.locale import __
@@ -115,7 +114,7 @@ def repr_domxml(node, length=80):
     try:
         text = node.asdom().toxml()
     except Exception:
-        text = text_type(node)
+        text = str(node)
     if length and len(text) > length:
         text = text[:length] + '...'
     return text
@@ -398,7 +397,7 @@ def inline_all_toctrees(builder, docnameset, docname, tree, colorfunc, traversed
     tree = cast(nodes.document, tree.deepcopy())
     for toctreenode in tree.traverse(addnodes.toctree):
         newnodes = []
-        includefiles = map(text_type, toctreenode['includefiles'])
+        includefiles = map(str, toctreenode['includefiles'])
         for includefile in includefiles:
             if includefile not in traversed:
                 try:
diff --git a/sphinx/util/pycompat.py b/sphinx/util/pycompat.py
index 0256ce0c2..df310368e 100644
--- a/sphinx/util/pycompat.py
+++ b/sphinx/util/pycompat.py
@@ -14,8 +14,6 @@ from html import escape as htmlescape  # NOQA
 from io import TextIOWrapper  # NOQA
 from textwrap import indent  # NOQA
 
-from six import text_type
-
 from sphinx.deprecation import RemovedInSphinx40Warning
 from sphinx.locale import __
 from sphinx.util import logging
@@ -64,7 +62,7 @@ def convert_with_2to3(filepath):
         lineno, offset = err.context[1]
         # try to match ParseError details with SyntaxError details
         raise SyntaxError(err.msg, (filepath, lineno, offset, err.value))
-    return text_type(tree)
+    return str(tree)
 
 
 class UnicodeMixin:
diff --git a/sphinx/util/typing.py b/sphinx/util/typing.py
index cf6c49daf..ecfd61f01 100644
--- a/sphinx/util/typing.py
+++ b/sphinx/util/typing.py
@@ -12,7 +12,6 @@ from typing import Any, Callable, Dict, List, Tuple, Union
 
 from docutils import nodes
 from docutils.parsers.rst.states import Inliner
-from six import text_type
 
 
 # An entry of Directive.option_spec
@@ -22,11 +21,11 @@ DirectiveOption = Callable[[str], Any]
 TextlikeNode = Union[nodes.Text, nodes.TextElement]
 
 # common role functions
-RoleFunction = Callable[[text_type, text_type, text_type, int, Inliner, Dict, List[text_type]],
+RoleFunction = Callable[[str, str, str, int, Inliner, Dict, List[str]],
                         Tuple[List[nodes.Node], List[nodes.system_message]]]
 
 # title getter functions for enumerable nodes (see sphinx.domains.std)
-TitleGetter = Callable[[nodes.Node], text_type]
+TitleGetter = Callable[[nodes.Node], str]
 
 # inventory data on memory
 Inventory = Dict[str, Dict[str, Tuple[str, str, str, str]]]
diff --git a/sphinx/writers/latex.py b/sphinx/writers/latex.py
index 4b0914a16..e6a3f0440 100644
--- a/sphinx/writers/latex.py
+++ b/sphinx/writers/latex.py
@@ -20,7 +20,6 @@ from typing import Iterable, cast
 
 from docutils import nodes, writers
 from docutils.writers.latex2e import Babel
-from six import text_type
 
 from sphinx import addnodes
 from sphinx import highlighting
@@ -784,7 +783,7 @@ class LaTeXTranslator(SphinxTranslator):
 
     def idescape(self, id):
         # type: (str) -> str
-        return '\\detokenize{%s}' % text_type(id).translate(tex_replace_map).\
+        return '\\detokenize{%s}' % str(id).translate(tex_replace_map).\
             encode('ascii', 'backslashreplace').decode('ascii').\
             replace('\\', '_')
 
@@ -805,34 +804,34 @@ class LaTeXTranslator(SphinxTranslator):
         figure = self.builder.config.numfig_format['figure'].split('%s', 1)
         if len(figure) == 1:
             ret.append('\\def\\fnum@figure{%s}\n' %
-                       text_type(figure[0]).strip().translate(tex_escape_map))
+                       str(figure[0]).strip().translate(tex_escape_map))
         else:
-            definition = text_type(figure[0]).strip().translate(tex_escape_map)
+            definition = str(figure[0]).strip().translate(tex_escape_map)
             ret.append(self.babel_renewcommand('\\figurename', definition))
             if figure[1]:
                 ret.append('\\makeatletter\n')
                 ret.append('\\def\\fnum@figure{\\figurename\\thefigure%s}\n' %
-                           text_type(figure[1]).strip().translate(tex_escape_map))
+                           str(figure[1]).strip().translate(tex_escape_map))
                 ret.append('\\makeatother\n')
 
         table = self.builder.config.numfig_format['table'].split('%s', 1)
         if len(table) == 1:
             ret.append('\\def\\fnum@table{%s}\n' %
-                       text_type(table[0]).strip().translate(tex_escape_map))
+                       str(table[0]).strip().translate(tex_escape_map))
         else:
-            definition = text_type(table[0]).strip().translate(tex_escape_map)
+            definition = str(table[0]).strip().translate(tex_escape_map)
             ret.append(self.babel_renewcommand('\\tablename', definition))
             if table[1]:
                 ret.append('\\makeatletter\n')
                 ret.append('\\def\\fnum@table{\\tablename\\thetable%s}\n' %
-                           text_type(table[1]).strip().translate(tex_escape_map))
+                           str(table[1]).strip().translate(tex_escape_map))
                 ret.append('\\makeatother\n')
 
         codeblock = self.builder.config.numfig_format['code-block'].split('%s', 1)
         if len(codeblock) == 1:
             pass  # FIXME
         else:
-            definition = text_type(codeblock[0]).strip().translate(tex_escape_map)
+            definition = str(codeblock[0]).strip().translate(tex_escape_map)
             ret.append(self.babel_renewcommand('\\literalblockname', definition))
             if codeblock[1]:
                 pass  # FIXME
@@ -849,7 +848,7 @@ class LaTeXTranslator(SphinxTranslator):
                 if i > 0:
                     ret.append('\\indexspace\n')
                 ret.append('\\bigletter{%s}\n' %
-                           text_type(letter).translate(tex_escape_map))
+                           str(letter).translate(tex_escape_map))
                 for entry in entries:
                     if not entry[3]:
                         continue
@@ -2028,7 +2027,7 @@ class LaTeXTranslator(SphinxTranslator):
             id = node.get('refuri', '')[1:].replace('#', ':')
 
         title = node.get('title', '%s')
-        title = text_type(title).translate(tex_escape_map).replace('\\%s', '%s')
+        title = str(title).translate(tex_escape_map).replace('\\%s', '%s')
         if '\\{name\\}' in title or '\\{number\\}' in title:
             # new style format (cf. "Fig.%{number}")
             title = title.replace('\\{name\\}', '{name}').replace('\\{number\\}', '{number}')
@@ -2476,7 +2475,7 @@ class LaTeXTranslator(SphinxTranslator):
 
     def encode(self, text):
         # type: (str) -> str
-        text = text_type(text).translate(tex_escape_map)
+        text = str(text).translate(tex_escape_map)
         if self.literal_whitespace:
             # Insert a blank before the newline, to avoid
             # ! LaTeX Error: There's no line here to end.
diff --git a/tests/test_domain_cpp.py b/tests/test_domain_cpp.py
index ab9cf9be2..6da91df82 100644
--- a/tests/test_domain_cpp.py
+++ b/tests/test_domain_cpp.py
@@ -12,7 +12,6 @@ import re
 import sys
 
 import pytest
-from six import text_type
 
 import sphinx.domains.cpp as cppDomain
 from sphinx import addnodes
@@ -39,7 +38,7 @@ def check(name, input, idDict, output=None):
     if output is None:
         output = input
     ast = parse(name, input)
-    res = text_type(ast)
+    res = str(ast)
     if res != output:
         print("")
         print("Input:    ", input)
diff --git a/tests/test_domain_py.py b/tests/test_domain_py.py
index bdb9f5fec..9d24d138e 100644
--- a/tests/test_domain_py.py
+++ b/tests/test_domain_py.py
@@ -11,7 +11,6 @@
 import pytest
 from docutils import nodes
 from mock import Mock
-from six import text_type
 
 from sphinx import addnodes
 from sphinx.domains.python import py_sig_re, _pseudo_parse_arglist, PythonDomain
@@ -30,22 +29,22 @@ def parse(sig):
 
 def test_function_signatures():
     rv = parse('func(a=1) -> int object')
-    assert text_type(rv) == 'a=1'
+    assert rv == 'a=1'
 
     rv = parse('func(a=1, [b=None])')
-    assert text_type(rv) == 'a=1, [b=None]'
+    assert rv == 'a=1, [b=None]'
 
     rv = parse('func(a=1[, b=None])')
-    assert text_type(rv) == 'a=1, [b=None]'
+    assert rv == 'a=1, [b=None]'
 
     rv = parse("compile(source : string, filename, symbol='file')")
-    assert text_type(rv) == "source : string, filename, symbol='file'"
+    assert rv == "source : string, filename, symbol='file'"
 
     rv = parse('func(a=[], [b=None])')
-    assert text_type(rv) == 'a=[], [b=None]'
+    assert rv == 'a=[], [b=None]'
 
     rv = parse('func(a=[][, b=None])')
-    assert text_type(rv) == 'a=[], [b=None]'
+    assert rv == 'a=[], [b=None]'
 
 
 @pytest.mark.sphinx('dummy', testroot='domain-py')
diff --git a/tests/test_quickstart.py b/tests/test_quickstart.py
index f990de857..0085f257e 100644
--- a/tests/test_quickstart.py
+++ b/tests/test_quickstart.py
@@ -12,7 +12,6 @@ import time
 from io import StringIO
 
 import pytest
-from six import text_type
 
 from sphinx import application
 from sphinx.cmd import quickstart as qs
@@ -35,7 +34,6 @@ def mock_input(answers, needanswer=False):
             raise AssertionError('answer for %r missing and no default '
                                  'present' % prompt)
         called.add(prompt)
-        prompt = text_type(prompt)
         for question in answers:
             if prompt.startswith(qs.PROMPT_PREFIX + question):
                 return answers[question]