added test coverage; refactor

Author: engcom-Charlie

app/code/Magento/Config/Model/Config/PathValidator.php

@@ -6,6 +6,7 @@
 
 namespace Magento\Config\Model\Config;
 
+use Magento\Config\Model\Config\Structure\Element\Field;
 use Magento\Framework\Exception\ValidatorException;
 
 /**
@@ -41,10 +42,10 @@ public function __construct(Structure $structure)
     public function validate($path)
     {
         $element = $this->structure->getElementByConfigPath($path);
-        if ($element->getConfigPath()) {
+        if ($element instanceof Field && $element->getConfigPath()) {
             $path = $element->getConfigPath();
         }
-        
+
         $allPaths = $this->structure->getFieldPaths();
 
         if (!array_key_exists($path, $allPaths)) {

dev/tests/integration/testsuite/Magento/Config/Console/Command/ConfigSetCommandTest.php

@@ -7,6 +7,7 @@
 namespace Magento\Config\Console\Command;
 
 use Magento\Config\Model\Config\Backend\Admin\Custom;
+use Magento\Config\Model\Config\PathValidator;
 use Magento\Config\Model\Config\Structure\Converter;
 use Magento\Config\Model\Config\Structure\Data as StructureData;
 use Magento\Directory\Model\Currency;
@@ -444,6 +445,15 @@ public function configSetValidDataProvider()
         ];
     }
 
+    /**
+     * Test validate path when field has custom config_path
+     */
+    public function testValidatePathWithCustomConfigPath(): void
+    {
+        $pathValidator = $this->objectManager->get(PathValidator::class);
+        $this->assertTrue($pathValidator->validate('general/group/subgroup/second_field'));
+    }
+
     /**
      * Set configuration and check this value from DB with success message this command should display
      *

dev/tests/integration/testsuite/Magento/Config/_files/system.xml

@@ -13,6 +13,10 @@
                     <field id="field" translate="label" type="text" sortOrder="100" showInDefault="1" showInWebsite="1" showInStore="0">
                         <label>Label</label>
                     </field>
+                    <field id="second_field" translate="label" type="text" sortOrder="10" showInDefault="1" showInWebsite="1" showInStore="0">
+                        <label>Label Second</label>
+                        <config_path>custom/config_path/second_field</config_path>
+                    </field>
                 </group>
             </group>
         </section>