fix: registering new user with a name longer than 255 characters

openedx/core/djangoapps/user_authn/views/registration_form.py

@@ -148,6 +148,7 @@ class AccountCreationForm(forms.Form):
 
     _EMAIL_INVALID_MSG = _("A properly formatted e-mail is required")
     _NAME_TOO_SHORT_MSG = _("Your legal name must be a minimum of one character long")
+    _NAME_TOO_LONG_MSG = _("Your legal name is too long. It must not exceed %(max_length)s characters")
 
     # TODO: Resolve repetition
 
@@ -167,9 +168,11 @@ class AccountCreationForm(forms.Form):
 
     name = forms.CharField(
         min_length=accounts.NAME_MIN_LENGTH,
+        max_length=accounts.NAME_MAX_LENGTH,
         error_messages={
             "required": _NAME_TOO_SHORT_MSG,
             "min_length": _NAME_TOO_SHORT_MSG,
+            "max_length": _NAME_TOO_LONG_MSG % {"max_length": accounts.NAME_MAX_LENGTH},
         },
         validators=[validate_name]
     )

openedx/core/djangoapps/user_authn/views/tests/test_register.py

@@ -316,6 +316,30 @@ class RegistrationViewValidationErrorTest(
             }
         )
 
+    def test_register_fullname_max_lenghth_validation_error(self):
+        """
+        Full name error detection test if the length exceeds 255 characters.
+        """
+        expected_error_message = f"Your legal name is too long. It must not exceed {NAME_MAX_LENGTH} characters"
+
+        response = self.client.post(self.url, {
+            "email": self.EMAIL,
+            "name": "x" * 256,
+            "username": self.USERNAME,
+            "password": self.PASSWORD,
+            "honor_code": "true",
+        })
+        assert response.status_code == 400
+
+        response_json = json.loads(response.content.decode('utf-8'))
+        self.assertDictEqual(
+            response_json,
+            {
+                "name": [{"user_message": expected_error_message}],
+                "error_code": "validation-error"
+            }
+        )
+
     def test_register_fullname_html_validation_error(self):
         """
         Test for catching invalid full name errors