1 files changed, 50 insertions, 16 deletions
diff --git a/setuptools/config.py b/setuptools/config.py
index 9b9a0c45..af3a3bcb 100644
--- a/setuptools/config.py
+++ b/setuptools/config.py
@@ -1,22 +1,58 @@
-from __future__ import absolute_import, unicode_literals
+import ast
 import io
 import os
 import sys
 
 import warnings
 import functools
+import importlib
 from collections import defaultdict
 from functools import partial
 from functools import wraps
-from importlib import import_module
+import contextlib
 
 from distutils.errors import DistutilsOptionError, DistutilsFileError
 from setuptools.extern.packaging.version import LegacyVersion, parse
 from setuptools.extern.packaging.specifiers import SpecifierSet
-from setuptools.extern.six import string_types, PY3
 
 
-__metaclass__ = type
+class StaticModule:
+    """
+    Attempt to load the module by the name
+    """
+    def __init__(self, name):
+        spec = importlib.util.find_spec(name)
+        with open(spec.origin) as strm:
+            src = strm.read()
+        module = ast.parse(src)
+        vars(self).update(locals())
+        del self.self
+
+    def __getattr__(self, attr):
+        try:
+            return next(
+                ast.literal_eval(statement.value)
+                for statement in self.module.body
+                if isinstance(statement, ast.Assign)
+                for target in statement.targets
+                if isinstance(target, ast.Name) and target.id == attr
+            )
+        except Exception as e:
+            raise AttributeError(
+                "{self.name} has no attribute {attr}".format(**locals())
+            ) from e
+
+
+@contextlib.contextmanager
+def patch_path(path):
+    """
+    Add path to front of sys.path for the duration of the context.
+    """
+    try:
+        sys.path.insert(0, path)
+        yield
+    finally:
+        sys.path.remove(path)
 
 
 def read_configuration(
@@ -283,7 +319,7 @@ class ConfigHandler:
         """
         include_directive = 'file:'
 
-        if not isinstance(value, string_types):
+        if not isinstance(value, str):
             return value
 
         if not value.startswith(include_directive):
@@ -344,15 +380,16 @@ class ConfigHandler:
             elif '' in package_dir:
                 # A custom parent directory was specified for all root modules
                 parent_path = os.path.join(os.getcwd(), package_dir[''])
-        sys.path.insert(0, parent_path)
-        try:
-            module = import_module(module_name)
-            value = getattr(module, attr_name)
 
-        finally:
-            sys.path = sys.path[1:]
+        with patch_path(parent_path):
+            try:
+                # attempt to load value statically
+                return getattr(StaticModule(module_name), attr_name)
+            except Exception:
+                # fallback to simple import
+                module = importlib.import_module(module_name)
 
-        return value
+        return getattr(module, attr_name)
 
     @classmethod
     def _get_parser_compound(cls, *parse_methods):
@@ -517,7 +554,7 @@ class ConfigMetadataHandler(ConfigHandler):
         if callable(version):
             version = version()
 
-        if not isinstance(version, string_types):
+        if not isinstance(version, str):
             if hasattr(version, '__iter__'):
                 version = '.'.join(map(str, version))
             else:
@@ -572,9 +609,6 @@ class ConfigOptionsHandler(ConfigHandler):
             return self._parse_list(value)
 
         findns = trimmed_value == find_directives[1]
-        if findns and not PY3:
-            raise DistutilsOptionError(
-                'find_namespace: directive is unsupported on Python < 3.3')
 
         # Read function arguments from a dedicated section.
         find_kwargs = self.parse_section_packages__find(