N°6414 Move existing AbstractSimpleField::Validate impl to custom validators

- LinkedSetField
- SelectObjectField
- MultipleChoicesField (warning this hierarchy contains non multiple value fields like SelectField !)

Also change AbstractValidator::Validate signature : now we are returning an array of error messages, so that we can return multiple ones

sources/Form/Validator/MultipleChoicesValidator.php

@@ -0,0 +1,59 @@
+<?php
+/*
+ * @copyright   Copyright (C) 2010-2023 Combodo SARL
+ * @license     http://opensource.org/licenses/AGPL-3.0
+ */
+
+namespace Combodo\iTop\Form\Validator;
+
+use utils;
+
+class MultipleChoicesValidator extends AbstractValidator
+{
+    public const VALIDATOR_NAME = 'multiple_choices_validator';
+
+    /** @var array List of possible choices */
+    private array $aChoices;
+
+    public function __construct(array $aChoices)
+    {
+        parent::__construct();
+        $this->aChoices = $aChoices;
+    }
+
+    /**
+     * @param mixed $value Warning can either be an array (if multiple values are allowed in the field) or a primitive : {@see \Combodo\iTop\Form\Field\MultipleChoicesField::GetCurrentValue()}
+     *
+     * @return array|string[]
+     */
+    public function Validate($value): array
+    {
+        $aErrorMessages = [];
+        if (false === is_array($value)) {
+            $this->CheckValueAgainstChoices($value, $aErrorMessages);
+
+            return $aErrorMessages;
+        }
+
+        if (count($value) === 0) {
+            return [];
+        }
+
+        /** @noinspection PhpUnusedLocalVariableInspection */
+        foreach ($value as $sCode => $valueItem) {
+            if (utils::IsNullOrEmptyString($valueItem)) {
+                continue;
+            }
+            $this->CheckValueAgainstChoices($valueItem, $aErrorMessages);
+        }
+
+        return $aErrorMessages;
+    }
+
+    private function CheckValueAgainstChoices(string $sValue, array &$aErrorMessages): void
+    {
+        if (false === array_key_exists($sValue, $this->aChoices)) {
+            $aErrorMessages[] = "Value ({$sValue}) is not part of the field possible values list";
+        }
+    }
+}