1 files changed, 41 insertions, 0 deletions
diff --git a/setuptools/tests/test_setopt.py b/setuptools/tests/test_setopt.py
new file mode 100644
index 00000000..36008632
--- /dev/null
+++ b/setuptools/tests/test_setopt.py
@@ -0,0 +1,41 @@
+import io
+import configparser
+
+from setuptools.command import setopt
+
+
+class TestEdit:
+    @staticmethod
+    def parse_config(filename):
+        parser = configparser.ConfigParser()
+        with io.open(filename, encoding='utf-8') as reader:
+            parser.read_file(reader)
+        return parser
+
+    @staticmethod
+    def write_text(file, content):
+        with io.open(file, 'wb') as strm:
+            strm.write(content.encode('utf-8'))
+
+    def test_utf8_encoding_retained(self, tmpdir):
+        """
+        When editing a file, non-ASCII characters encoded in
+        UTF-8 should be retained.
+        """
+        config = tmpdir.join('setup.cfg')
+        self.write_text(str(config), '[names]\njaraco=джарако')
+        setopt.edit_config(str(config), dict(names=dict(other='yes')))
+        parser = self.parse_config(str(config))
+        assert parser.get('names', 'jaraco') == 'джарако'
+        assert parser.get('names', 'other') == 'yes'
+
+    def test_case_retained(self, tmpdir):
+        """
+        When editing a file, case of keys should be retained.
+        """
+        config = tmpdir.join('setup.cfg')
+        self.write_text(str(config), '[names]\nFoO=bAr')
+        setopt.edit_config(str(config), dict(names=dict(oTher='yes')))
+        actual = config.read_text(encoding='ascii')
+        assert 'FoO' in actual
+        assert 'oTher' in actual