Include the details also in the invalid default value case too.

2 files changed, 25 insertions, 6 deletions

diff --git a/src/zope/configuration/config.py b/src/zope/configuration/config.py
index 4b843a9..0123021 100644
--- a/src/zope/configuration/config.py
+++ b/src/zope/configuration/config.py
@@ -1685,15 +1685,16 @@ def toargs(context, schema, data):
             try:
                 args[str(name)] = field.fromUnicode(s)
             except ValidationError as v:
-                reraise(ConfigurationError("Invalid value for %r: %r" % (n, v)).add_details(v),
+                reraise(ConfigurationError("Invalid value for %r" % (n)).add_details(v),
                         None, sys.exc_info()[2])
         elif field.required:
             # if the default is valid, we can use that:
             default = field.default
             try:
                 field.validate(default)
-            except ValidationError:
-                raise ConfigurationError("Missing parameter:", n)
+            except ValidationError as v:
+                reraise(ConfigurationError("Missing parameter: %r" % (n,)).add_details(v),
+                        None, sys.exc_info()[2])
             args[str(name)] = default
 
     if data:
diff --git a/src/zope/configuration/tests/test_config.py b/src/zope/configuration/tests/test_config.py
index 4a62ea0..f8bebe7 100644
--- a/src/zope/configuration/tests/test_config.py
+++ b/src/zope/configuration/tests/test_config.py
@@ -1789,7 +1789,18 @@ class Test_toargs(unittest.TestCase):
         with self.assertRaises(ConfigurationError) as exc:
             self._callFUT(context, ISchema, {})
         self.assertEqual(exc.exception.args,
-                         ('Missing parameter:', 'no_default'))
+                         ("Missing parameter: 'no_default'",))
+
+        # It includes the details of any validation failure;
+        # The rendering of the nested exception varies by Python version,
+        # sadly.
+        exception_str = str(exc.exception)
+        self.assertTrue(exception_str.startswith(
+            "Missing parameter: 'no_default'\n"
+        ), exception_str)
+        self.assertTrue(exception_str.endswith(
+            "RequiredMissing: no_default"
+        ), exception_str)
 
     def test_w_field_missing_but_default(self):
         from zope.interface import Interface
@@ -1810,8 +1821,15 @@ class Test_toargs(unittest.TestCase):
         with self.assertRaises(ConfigurationError) as exc:
             self._callFUT(context, ISchema, {'count': '-1'})
         self.assertEqual(exc.exception.args,
-                         ("Invalid value for 'count': TooSmall(-1, 0)",))
-
+                         ("Invalid value for 'count'",))
+
+        exception_str = str(exc.exception)
+        self.assertTrue(exception_str.startswith(
+            "Invalid value for 'count'\n"
+        ), exception_str)
+        self.assertTrue(exception_str.endswith(
+            "TooSmall: (-1, 0)"
+        ), exception_str)
 
 class Test_expand_action(unittest.TestCase):