Added check for section pattern in key and moved

invalid key checks to seperate function
python · jaraco · Feb 23, 2025 · Jan 16, 2025 · Jan 22, 2025 · Jan 22, 2025
commit 9cc3506b9ef43a8f21300f5ef82e572312ea70ad
@@ -163,7 +163,7 @@
            "MultilineContinuationError", "UnnamedSectionDisabledError",
            "ConfigParser", "RawConfigParser",
            "Interpolation", "BasicInterpolation",  "ExtendedInterpolation",
-           "SectionProxy", "ConverterMapping", "InvalidKeyError",
+           "SectionProxy", "ConverterMapping", "InvalidInputError",
            "DEFAULTSECT", "MAX_INTERPOLATION_DEPTH", "UNNAMED_SECTION")
 
 _default_dict = dict
@@ -375,10 +375,11 @@ class _UnnamedSection:
     def __repr__(self):
         return "<UNNAMED_SECTION>"
 
-class InvalidKeyError(Error):
+class InvalidInputError(Error):
     """Raised when attempting to write a key which contains any delimiters"""
-    def __init__(self):
-        Error.__init__(self, "Cannot write key that contains a delimiter")
+
+    def __init__(self, msg=''):
+        Error.__init__(self, msg)
 
 
 UNNAMED_SECTION = _UnnamedSection()
@@ -978,6 +979,7 @@ def _write_section(self, fp, section_name, section_items, delimiter, unnamed=Fal
         if not unnamed:
             fp.write("[{}]\n".format(section_name))
         for key, value in section_items:
+            self._validate_key_contents(key)
             value = self._interpolation.before_write(self, section_name, key,
                                                      value)
             if value is not None or not self._allow_no_value:
@@ -1218,6 +1220,15 @@ def _convert_to_boolean(self, value):
         if value.lower() not in self.BOOLEAN_STATES:
             raise ValueError('Not a boolean: %s' % value)
         return self.BOOLEAN_STATES[value.lower()]
+
+    def _validate_key_contents(self, key):
+        """Raises an InvalidInputError for any keys containing 
+        delimiters or a leading '['"""
+        if re.match(self.SECTCRE, key):
+            raise InvalidInputError("Cannot write keys matching section pattern")
+        for delim in self._delimiters:
+            if delim in key:
+                raise InvalidInputError("Cannot write key that contains delimiters")
 
     def _validate_value_types(self, *, section="", option="", value=""):
         """Raises a TypeError for illegal non-string values.
@@ -1239,9 +1250,6 @@ def _validate_value_types(self, *, section="", option="", value=""):
         if not self._allow_no_value or value:
             if not isinstance(value, str):
                 raise TypeError("option values must be strings")
-        for delim in self._delimiters:
-            if delim in option:
-                raise InvalidKeyError()
 
     @property
     def converters(self):

@@ -2173,16 +2173,29 @@ def test_disabled_error(self):
 
         with self.assertRaises(configparser.UnnamedSectionDisabledError):
             configparser.ConfigParser().add_section(configparser.UNNAMED_SECTION)
+
+class InvalidInputTestCase(unittest.TestCase):
+    """Tests for issue #65697, where configparser will write configs 
+    it parses back differently. Ex: keys containing delimiters or 
+    matching the section pattern"""
+
+    def test_delimiter_in_key(self):
+        cfg = configparser.ConfigParser(delimiters=('='))
+        cfg.add_section('section1')
+        cfg.set('section1', 'a=b', 'c')
+        output = io.StringIO()
+        with self.assertRaises(configparser.InvalidInputError):
+            cfg.write(output)
+        output.close()
 
-    def test_invalid_key(self):
-        cfg2file = configparser.ConfigParser()
-        cfg2file.add_section("section1")
-        with self.assertRaises(configparser.InvalidKeyError): 
-            cfg2file.set("section1", "one=two", "three")
-
-        with self.assertRaises(configparser.InvalidKeyError): 
-            cfg2file.set("section1", "one:two", "three")
-
+    def test_section_bracket_in_key(self):
+        cfg = configparser.ConfigParser()
+        cfg.add_section('section1')
+        cfg.set('section1', '[this parses back as a section]', 'foo')
+        output = io.StringIO()
+        with self.assertRaises(configparser.InvalidInputError):
+            cfg.write(output)
+        output.close()
 
 class MiscTestCase(unittest.TestCase):
     def test__all__(self):