Merge ~cjwatson/lazr.restful:remove-py2-only-code into lazr.restful:main

[Colin Watson]

Remove some Python-2-only code and dependencies

[Jürgen Gmach (jugmac00)]

LGTM - many occurrences of six left, but I assume there was no intention to remove six with this MP.

review: Approve

[Colin Watson (cjwatson)]

Yeah, I have a whole series that ultimately involves removing six, but it was a bit much to propose all at once.

diff --git a/setup.py b/setup.py
index 7f0ed89..1017963 100755
--- a/setup.py
+++ b/setup.py
@@ -65,7 +65,6 @@ setup(
         "six>=1.13.0",
         "testtools",
         "van.testing",
-        'wsgiref; python_version < "3"',
         "zope.component [zcml]",
         "zope.configuration",
         "zope.datetime",
@@ -74,8 +73,7 @@ setup(
         "zope.pagetemplate",
         "zope.processlifetime",
         "zope.proxy",
-        'zope.publisher; python_version < "3"',
-        'zope.publisher>=6.0.0; python_version >= "3"',
+        "zope.publisher>=6.0.0",
         "zope.schema",
         "zope.security",
         "zope.traversing",
diff --git a/src/lazr/restful/_resource.py b/src/lazr/restful/_resource.py
index 45f717e..2d4a486 100644
--- a/src/lazr/restful/_resource.py
+++ b/src/lazr/restful/_resource.py
@@ -29,6 +29,8 @@ __all__ = [
 from collections import OrderedDict
 from email.utils import formatdate
 import copy
+import hashlib
+import html
 from operator import itemgetter
 import os
 import simplejson
@@ -36,21 +38,6 @@ import simplejson.encoder
 import sys
 import time
 
-# Import SHA in a way compatible with both Python 2.4 and Python 2.6.
-try:
-    import hashlib
-
-    sha_constructor = hashlib.sha1
-except ImportError:
-    import sha
-
-    sha_constructor = sha.new
-
-try:
-    from html import escape
-except ImportError:
-    from cgi import escape
-
 from zope.component import (
     adapter,
     getAdapters,
@@ -167,7 +154,7 @@ def decode_value(value):
 
 def _default_html_renderer(value):
     """The default technique for rendering a value as an HTML snippet."""
-    return escape(str(value), quote=False)
+    return html.escape(str(value), quote=False)
 
 
 @adapter(Interface, IField, IWebServiceClientRequest)
@@ -442,7 +429,7 @@ class HTTPResource:
 
         core_hashes = []
         for core in etag_cores:
-            hash_object = sha_constructor()
+            hash_object = hashlib.sha1()
             hash_object.update(core)
             core_hashes.append(hash_object)
 
diff --git a/src/lazr/restful/declarations.py b/src/lazr/restful/declarations.py
index 886eedb..1ea9e21 100644
--- a/src/lazr/restful/declarations.py
+++ b/src/lazr/restful/declarations.py
@@ -56,7 +56,6 @@ from zope.schema import (
 from zope.schema.interfaces import (
     IField,
     IObject,
-    IText,
 )
 from zope.security.checker import CheckerPublic
 from zope.traversing.browser import absoluteURL
@@ -707,17 +706,6 @@ def _update_default_and_required_params(params, method_info):
         # a default, set it to the same as the method.
         if name in optional and param_def.default is None:
             default = optional[name]
-
-            # This is to work around the fact that all strings in
-            # zope schema are expected to be unicode, whereas it's
-            # really possible that the method's default is a simple
-            # string.
-            if (
-                six.PY2
-                and isinstance(default, str)
-                and IText.providedBy(param_def)
-            ):
-                default = unicode(default)  # noqa: F821
             param_def.default = default
             param_def.required = False
         elif name in required and param_def.default is not None:
diff --git a/src/lazr/restful/docs/webservice-declarations.rst b/src/lazr/restful/docs/webservice-declarations.rst
index 2db2286..964f5ff 100644
--- a/src/lazr/restful/docs/webservice-declarations.rst
+++ b/src/lazr/restful/docs/webservice-declarations.rst
@@ -910,9 +910,8 @@ The created interface is named with 'Entry' appended to the original
 name, and is in the same module
 
     >>> import sys
-    >>> entry_interface.__module__ == (
-    ...     'builtins' if sys.version_info[0] >= 3 else '__builtin__')
-    True
+    >>> entry_interface.__module__
+    'builtins'
     >>> entry_interface.__name__
     'IBookEntry_beta'
 
diff --git a/src/lazr/restful/docs/webservice-marshallers.rst b/src/lazr/restful/docs/webservice-marshallers.rst
index 20028f3..0d18d2a 100644
--- a/src/lazr/restful/docs/webservice-marshallers.rst
+++ b/src/lazr/restful/docs/webservice-marshallers.rst
@@ -31,11 +31,6 @@ across Python versions.
     ...             return '"%s"' % value
     ...         else:
     ...             return "'%s'" % value.replace("'", "\\'")
-    ...     elif isinstance(value, bytes):
-    ...         if six.PY2:
-    ...             return 'b%r' % value
-    ...         else:
-    ...             return repr(value)
     ...     else:
     ...         return repr(value)
 
diff --git a/src/lazr/restful/example/base/filemanager.py b/src/lazr/restful/example/base/filemanager.py
index 781bf88..98c70ce 100644
--- a/src/lazr/restful/example/base/filemanager.py
+++ b/src/lazr/restful/example/base/filemanager.py
@@ -5,20 +5,10 @@
 __all__ = ["FileManager", "ManagedFileResource"]
 
 import datetime
-
-# Import SHA in a way compatible with both Python 2.4 and Python 2.6.
-try:
-    import hashlib
-
-    sha_constructor = hashlib.sha1
-except ImportError:
-    import sha
-
-    sha_constructor = sha.new
-
-from zope.interface import implementer
+import hashlib
 
 import grokcore.component
+from zope.interface import implementer
 
 from lazr.restful import ReadOnlyResource
 from lazr.restful.example.base.interfaces import IFileManager
@@ -61,7 +51,7 @@ class ManagedFileResource(ReadOnlyResource):
         self.mediaType = mediaType
         self.filename = filename
         self.last_modified = last_modified
-        sum = sha_constructor()
+        sum = hashlib.sha1()
         sum.update(representation)
         self.etag = sum.hexdigest()
 
diff --git a/src/lazr/restful/testing/helpers.py b/src/lazr/restful/testing/helpers.py
index fc9c8b1..c0dd63c 100644
--- a/src/lazr/restful/testing/helpers.py
+++ b/src/lazr/restful/testing/helpers.py
@@ -52,10 +52,7 @@ def encode_response(response):
 
     :param response: an httplib HTTPResponse object.
     """
-    response_unicode = str(response)
-    if isinstance(response_unicode, bytes):  # Python 2
-        response_unicode = response_unicode.decode("utf-8")
-    return encode_unicode(response_unicode)
+    return encode_unicode(str(response))
 
 
 def encode_unicode(unicode_string):
diff --git a/src/lazr/restful/testing/webservice.py b/src/lazr/restful/testing/webservice.py
index a4405b1..148fd4c 100644
--- a/src/lazr/restful/testing/webservice.py
+++ b/src/lazr/restful/testing/webservice.py
@@ -572,19 +572,14 @@ class WebServiceResponseWrapper(ProxyBase):
         return self.getheader(key, default)
 
     def __str__(self):
-        if sys.version_info[0] >= 3:
-            # Reconstructing the original list of headers seems to involve a
-            # bit more effort on Python 3.
-            def normalize(key):
-                """Normalize an HTTP header name to title case."""
-                return "-".join(s.title() for s in key.split("-"))
-
-            headers = [
-                "%s: %s\n" % (normalize(key), value)
-                for key, value in self.msg.items()
-            ]
-        else:
-            headers = self.msg.headers
+        def normalize(key):
+            """Normalize an HTTP header name to title case."""
+            return "-".join(s.title() for s in key.split("-"))
+
+        headers = [
+            "%s: %s\n" % (normalize(key), value)
+            for key, value in self.msg.items()
+        ]
         body = self.body.decode("UTF-8")
         return "HTTP/1.1 %s %s\n%s\n%s" % (
             self.status,