Correctly parse cmdclass in setup.cfg. Fixes pypa#2570

changelog.d/2570.change.rst

@@ -0,0 +1 @@
+Correctly parse cmdclass in setup.cfg.

setuptools/config.py

@@ -574,6 +574,7 @@ def parsers(self):
         parse_list_semicolon = partial(self._parse_list, separator=';')
         parse_bool = self._parse_bool
         parse_dict = self._parse_dict
+        parse_cmdclass = self._parse_cmdclass
 
         return {
             'zip_safe': parse_bool,
@@ -594,6 +595,22 @@ def parsers(self):
             'entry_points': self._parse_file,
             'py_modules': parse_list,
             'python_requires': SpecifierSet,
+            'cmdclass': parse_cmdclass,
+        }
+
+    def _parse_cmdclass(self, value):
+        def resolve_class(qualified_class_name):
+            idx = qualified_class_name.rfind('.')
+            class_name = qualified_class_name[idx+1:]
+            pkg_name = qualified_class_name[:idx]
+
+            module = __import__(pkg_name)
+
+            return getattr(module, class_name)
+
+        return {
+            k: resolve_class(v)
+            for k, v in self._parse_dict(value).items()
         }
 
     def _parse_packages(self, value):

setuptools/tests/test_config.py

@@ -1,3 +1,6 @@
+import types
+import sys
+
 import contextlib
 import configparser
 
@@ -7,6 +10,7 @@
 from mock import patch
 from setuptools.dist import Distribution, _Distribution
 from setuptools.config import ConfigHandler, read_configuration
+from distutils.core import Command
 from .textwrap import DALS
 
 
@@ -853,6 +857,26 @@ def test_python_requires_invalid(self, tmpdir):
             with get_dist(tmpdir) as dist:
                 dist.parse_config_files()
 
+    def test_cmdclass(self, tmpdir):
+        class CustomCmd(Command):
+            pass
+
+        m = types.ModuleType('custom_build', 'test package')
+
+        m.__dict__['CustomCmd'] = CustomCmd
+
+        sys.modules['custom_build'] = m
+
+        fake_env(
+            tmpdir,
+            '[options]\n'
+            'cmdclass =\n'
+            '    customcmd = custom_build.CustomCmd\n'
+        )
+
+        with get_dist(tmpdir) as dist:
+            assert dist.cmdclass == {'customcmd': CustomCmd}
+
 
 saved_dist_init = _Distribution.__init__