From 955ea8115343695955bc55a4ff3d4bc6b6c01e3a Mon Sep 17 00:00:00 2001
From: Steve Boyd <emteknetnz@gmail.com>
Date: Fri, 7 Feb 2025 12:28:04 +1300
Subject: [PATCH] DOC Show more information in ValidationException message

---
 en/02_Developer_Guides/00_Model/09_Validation.md | 3 +++
 en/08_Changelogs/6.0.0.md                        | 9 +++++++++
 2 files changed, 12 insertions(+)

diff --git a/en/02_Developer_Guides/00_Model/09_Validation.md b/en/02_Developer_Guides/00_Model/09_Validation.md
index 57ce8d52..19327651 100644
--- a/en/02_Developer_Guides/00_Model/09_Validation.md
+++ b/en/02_Developer_Guides/00_Model/09_Validation.md
@@ -44,6 +44,9 @@ sub-classes to specify custom validation, or use the `updateValidate()` extensio
 
 Invalid objects won't be able to be written - a [`ValidationException`](api:SilverStripe\Core\Validation\ValidationException) will be thrown and no write will occur.
 
+If appropriate, you can call [`ValidationResult::setModelClass()`](api:SilverStripe\Core\Validation\ValidationResult::setModelClass())
+and [`ValidationResult::setRecordID()`](api:SilverStripe\Core\Validation\ValidationResult::setRecordID()) on your `ValidationResult` instance to set the class and ID of the object being validated. This additional info will show in the validation error messages in a CLI context, as well as in a non-CLI context if the current controller is an instance or a subclass of a controller configured in the [`ValidationException.show_additional_info_non_cli_controllers`](api:SilverStripe\Core\Validation\ValidationException->show_additional_info_non_cli_controllers) configuration.
+
 The return value of `validate()` is a [`ValidationResult`](api:SilverStripe\Core\Validation\ValidationResult) object.
 
 ```php
diff --git a/en/08_Changelogs/6.0.0.md b/en/08_Changelogs/6.0.0.md
index 966d70e9..994902db 100644
--- a/en/08_Changelogs/6.0.0.md
+++ b/en/08_Changelogs/6.0.0.md
@@ -50,6 +50,7 @@ title: 6.0.0 (unreleased)
   - [Update JS MIME type, remove `type` in `<script>` tags](#js-mime-type-update)
   - [`getSchemaDataDefaults()` now includes attributes](#formfield-schema-data)
   - [Remember me token rotation](#remember-me-token-rotation)
+  - [Validation exceptions shows additional info in some contexts](#validation-exception-info)
 - [Full list of removed and changed API (by module, alphabetically)](#api-removed-and-changed)
 
 ## Change to commercially supported modules {#changes-to-support}
@@ -1176,6 +1177,14 @@ If you were calling `getSchemaData()` in your `getAttributes()` method in a `For
 
 The related `onAfterRenewToken` extension hook has been renamed to `onAfterRenewSession`, and is triggered at the same logical step in the session renewal process.
 
+### Validation exceptions shows additional info in some contexts {#validation-exception-info}
+
+[`ValidationResult`](api:SilverStripe\Core\Validation\ValidationResult) objects created by [`DataObject::validate()`](api:SilverStripe\ORM\DataObject::validate()) now includes additional information about validation exceptions including the field name that failed validation, and if applicable the model class and record ID. This additional information will be included in the validation message by [`ValidationException`](api:SilverStripe\Core\Validation\ValidationException) if the validation exception happened in a CLI context, or in an HTTP context if the current controller is an instance contained in the [`ValidationException.show_additional_info_non_cli_controllers`](api:SilverStripe\Core\Validation\ValidationException->show_additional_info_non_cli_controllers) configuration or a subclass. By default only [`DevelopmentAdmin`](api:SilverStripe\Dev\DevelopmentAdmin) and subclasses are configured to show additonal information.
+
+This is done to help developers debug validation issues that happen outside of a UX context more easily, such as validation exceptions that occur during a `dev/build`.
+
+The value of the field that failed validation is intentially not included in the output, as it could contain sensitive information e.g. an API token.
+
 ### Full list of removed and changed API (by module, alphabetically) {#api-removed-and-changed}
 
 <!--- Changes below this line will be automatically regenerated -->