Implemented find() configuration support for `packages`.

docs/setuptools.txt

@@ -2448,6 +2448,11 @@ boilerplate code in some cases.
     pdf = ReportLab>=1.2; RXP
     rest = docutils>=0.3; pack ==1.1, ==1.3
 
+    [options.packages.find]
+    exclude =
+        src.subpackage1
+        src.subpackage2
+
 
 Metadata and options could be set in sections with the same names.
 
@@ -2486,13 +2491,13 @@ Type names used below:
 * ``list-semi`` - dangling list or semicolon-separated values string
 * ``bool`` -  ``True`` is 1, yes, true
 * ``dict`` - list-comma where keys from values are separated by =
+* ``section`` - values could be read from a dedicated (sub)section
 
 
 Special directives:
 
 * ``attr:`` - value could be read from module attribute
 * ``file:`` - value could be read from a file
-* ``section:`` - values could be read from a dedicated (sub)section
 
 
 .. note::
@@ -2529,8 +2534,10 @@ requires                              list-comma
 obsoletes                             list-comma
 =================  =================  =====
 
-**version** - ``attr:`` supports callables; supports iterables;
-unsupported types are casted using ``str()``.
+.. note::
+
+    **version** - ``attr:`` supports callables; supports iterables;
+    unsupported types are casted using ``str()``.
 
 
 Options
@@ -2560,6 +2567,13 @@ exclude_package_data     section
 namespace_packages       list-comma
 =======================  =====
 
+.. note::
+
+    **packages** - ``find:`` directive can be further configured
+    in a dedicated subsection `options.packages.find`. This subsection
+    accepts the same keys as `setuptools.find` function:
+    `where`, `include`, `exclude`.
+
 
 Configuration API
 =================

setuptools/config.py

@@ -361,7 +361,10 @@ class ConfigHandler(object):
                 method_postfix = '_%s' % section_name
 
             section_parser_method = getattr(
-                self, 'parse_section%s' % method_postfix, None)
+                self,
+                # Dots in section names are tranlsated into dunderscores.
+                ('parse_section%s' % method_postfix).replace('.', '__'),
+                None)
 
             if section_parser_method is None:
                 raise DistutilsOptionError(
@@ -481,8 +484,34 @@ class ConfigOptionsHandler(ConfigHandler):
         if not value.startswith(find_directive):
             return self._parse_list(value)
 
+        # Read function arguments from a dedicated section.
+        find_kwargs = self.parse_section_packages__find(
+            self.sections.get('packages.find', {}))
+
         from setuptools import find_packages
-        return find_packages()
+
+        return find_packages(**find_kwargs)
+
+    def parse_section_packages__find(self, section_options):
+        """Parses `packages.find` configuration file section.
+
+        To be used in conjunction with _parse_packages().
+
+        :param dict section_options:
+        """
+        section_data = self._parse_section_to_dict(
+            section_options, self._parse_list)
+
+        valid_keys = ['where', 'include', 'exclude']
+
+        find_kwargs = dict(
+            [(k, v) for k, v in section_data.items() if k in valid_keys and v])
+
+        where = find_kwargs.get('where')
+        if where is not None:
+            find_kwargs['where'] = where[0]  # cast list to single val
+
+        return find_kwargs
 
     def parse_section_entry_points(self, section_options):
         """Parses `entry_points` configuration file section.

setuptools/tests/test_config.py

@@ -446,6 +446,44 @@ class TestOptions:
         with get_dist(tmpdir) as dist:
             assert dist.packages == ['fake_package']
 
+    def test_find_directive(self, tmpdir):
+        dir_package, config = fake_env(
+            tmpdir,
+            '[options]\n'
+            'packages = find:\n'
+        )
+
+        dir_sub_one, _ = make_package_dir('sub_one', dir_package)
+        dir_sub_two, _ = make_package_dir('sub_two', dir_package)
+
+        with get_dist(tmpdir) as dist:
+            assert dist.packages == [
+                'fake_package', 'fake_package.sub_two', 'fake_package.sub_one']
+
+        config.write(
+            '[options]\n'
+            'packages = find:\n'
+            '\n'
+            '[options.packages.find]\n'
+            'where = .\n'
+            'include =\n'
+            '    fake_package.sub_one\n'
+            '    two\n'
+        )
+        with get_dist(tmpdir) as dist:
+            assert dist.packages == ['fake_package.sub_one']
+
+        config.write(
+            '[options]\n'
+            'packages = find:\n'
+            '\n'
+            '[options.packages.find]\n'
+            'exclude =\n'
+            '    fake_package.sub_one\n'
+        )
+        with get_dist(tmpdir) as dist:
+            assert dist.packages == ['fake_package',  'fake_package.sub_two']
+
     def test_extras_require(self, tmpdir):
         fake_env(
             tmpdir,