feat: Validation::run() accepts DB connection

deptrac.yaml

@@ -219,6 +219,7 @@ parameters:
       - I18n
     Validation:
       - HTTP
+      - Database
     View:
       - Cache
   skip_violations:

system/Validation/Validation.php

@@ -14,6 +14,7 @@
 namespace CodeIgniter\Validation;
 
 use Closure;
+use CodeIgniter\Database\BaseConnection;
 use CodeIgniter\HTTP\Exceptions\HTTPException;
 use CodeIgniter\HTTP\IncomingRequest;
 use CodeIgniter\HTTP\Method;
@@ -128,14 +129,11 @@ public function __construct($config, RendererInterface $view)
      * Runs the validation process, returning true/false determining whether
      * validation was successful or not.
      *
-     * @param array|null  $data    The array of data to validate.
-     * @param string|null $group   The predefined group of rules to apply.
-     * @param string|null $dbGroup The database group to use.
-     *
-     * @TODO Type ?string for $dbGroup should be removed.
-     *      See https://github.com/codeigniter4/CodeIgniter4/issues/6723
+     * @param array|null                                 $data    The array of data to validate.
+     * @param string|null                                $group   The predefined group of rules to apply.
+     * @param array|BaseConnection|non-empty-string|null $dbGroup The database group to use.
      */
-    public function run(?array $data = null, ?string $group = null, ?string $dbGroup = null): bool
+    public function run(?array $data = null, ?string $group = null, $dbGroup = null): bool
     {
         if ($data === null) {
             $data = $this->data;

system/Validation/ValidationInterface.php

@@ -13,6 +13,7 @@
 
 namespace CodeIgniter\Validation;
 
+use CodeIgniter\Database\BaseConnection;
 use CodeIgniter\HTTP\RequestInterface;
 
 /**
@@ -24,11 +25,11 @@ interface ValidationInterface
      * Runs the validation process, returning true/false determining whether
      * validation was successful or not.
      *
-     * @param array|null  $data    The array of data to validate.
-     * @param string|null $group   The predefined group of rules to apply.
-     * @param string|null $dbGroup The database group to use.
+     * @param array|null                                 $data    The array of data to validate.
+     * @param string|null                                $group   The predefined group of rules to apply.
+     * @param array|BaseConnection|non-empty-string|null $dbGroup The database group to use.
      */
-    public function run(?array $data = null, ?string $group = null, ?string $dbGroup = null): bool;
+    public function run(?array $data = null, ?string $group = null, $dbGroup = null): bool;
 
     /**
      * Check; runs the validation process, returning true or false

tests/system/Validation/StrictRules/DatabaseRelatedRulesTest.php

@@ -85,6 +85,17 @@ public function testIsUniqueTrue(): void
         $this->assertTrue($this->validation->run($data));
     }
 
+    public function testIsUniqueWithDBConnection(): void
+    {
+        $db = db_connect();
+        $this->validation->setRules(['email' => 'is_unique[user.email]']);
+
+        $data   = ['email' => 'derek@world.co.uk'];
+        $result = $this->validation->run($data, null, $db);
+
+        $this->assertTrue($result);
+    }
+
     public function testIsUniqueWithInvalidDBGroup(): void
     {
         $this->expectException(InvalidArgumentException::class);

user_guide_src/source/changelogs/v4.5.0.rst

@@ -80,6 +80,8 @@ Interface Changes
   the ``ResponseInterface::setCookie()`` has been fixed from ``''`` to ``0``.
 - **Logger:** The `psr/log <https://packagist.org/packages/psr/log>`_ package has
   been upgraded to v3.0.0.
+- **Validation:** The method signature of ``ValidationInterface::run()`` has been
+  changed. The ``?string`` typehint on the ``$dbGroup`` parameter was removed.
 
 .. _v450-method-signature-changes:
 
@@ -129,6 +131,8 @@ Others
   that implements the PSR-3 interface have been fixed. The ``bool`` return
   types are changed to ``void``. The ``$message`` parameters now have
   ``string|Stringable`` types.
+- **Validation:** The method signature of ``Validation::run()`` has been
+  changed. The ``?string`` typehint on the ``$dbGroup`` parameter was removed.
 
 .. _v450-removed-deprecated-items:
 
@@ -294,8 +298,12 @@ findAll(0) Behavior
 Libraries
 =========
 
-- **Validation:** Added the new rule ``field_exists`` that checks the filed
-  exists in the data to be validated.
+- **Validation:**
+    - Added the new rule ``field_exists`` that checks the filed exists in the
+      data to be validated.
+    - The ``$dbGroup`` parameter of ``Validation::run()`` now accepts not only
+      a database group name, but also a database connection instance or an array
+      of database settings.
 
 Helpers and Functions
 =====================

user_guide_src/source/installation/upgrade_450.rst

@@ -199,6 +199,11 @@ using them, upgrade your code. See :ref:`ChangeLog <v450-removed-deprecated-item
 Breaking Enhancements
 *********************
 
+- The method signatures of ``Validation::run()`` and ``ValidationInterface::run()``
+  have been changed. The ``?string`` typehint on the ``$dbGroup`` parameter was
+  removed. Extending classes should likewise remove the parameter so as not to
+  break LSP.
+
 Project Files
 *************