Include setup_requires directive in Distribution attributes and metadata. Fixes #239.

CHANGES.txt

@@ -2,6 +2,14 @@
 CHANGES
 =======
 
+---
+5.5
+---
+
+* Issue #239: Setuptools now includes the setup_requires directive on
+  Distribution objects and validates the syntax just like install_requires
+  and tests_require directives.
+
 -----
 5.4.2
 -----

setup.py

@@ -144,6 +144,7 @@ setup_params = dict(
             "extras_require         = setuptools.dist:check_extras",
             "install_requires       = setuptools.dist:check_requirements",
             "tests_require          = setuptools.dist:check_requirements",
+            "setup_reqires          = setuptools.dist:check_requirements",
             "entry_points           = setuptools.dist:check_entry_points",
             "test_suite             = setuptools.dist:check_test_suite",
             "zip_safe               = setuptools.dist:assert_bool",

setuptools/dist.py

@@ -259,7 +259,7 @@ class Distribution(_Distribution):
             self.dependency_links = attrs.pop('dependency_links', [])
             assert_string_list(self,'dependency_links',self.dependency_links)
         if attrs and 'setup_requires' in attrs:
-            self.fetch_build_eggs(attrs.pop('setup_requires'))
+            self.fetch_build_eggs(attrs['setup_requires'])
         for ep in pkg_resources.iter_entry_points('distutils.setup_keywords'):
             if not hasattr(self,ep.name):
                 setattr(self,ep.name,None)