ENGCOM-5545: 'New Tax Rate' missing validation => data is automatically changed when saving issue 23967 #23968

 - Merge Pull Request #23968 from edenduong/magento2:2.3-bugfix/fix-validate-tax-rate-issue23967
 - Merged commits:
   1. e1197cb

Author: magento-engcom-team

app/code/Magento/Tax/Block/Adminhtml/Rate/Form.php

@@ -9,6 +9,8 @@
  *
  * @author      Magento Core Team <core@magentocommerce.com>
  */
+declare(strict_types=1);
+
 namespace Magento\Tax\Block\Adminhtml\Rate;
 
 use Magento\Framework\Exception\NoSuchEntityException;
@@ -228,7 +230,8 @@ protected function _prepareForm()
                 'note' => __(
                     "'*' - matches any; 'xyz*' - matches any that begins on 'xyz' and are not longer than %1.",
                     $this->_taxData->getPostCodeSubStringLength()
-                )
+                ),
+                'class' => 'validate-length maximum-length-' . $this->_taxData->getPostCodeSubStringLength()
             ]
         );
 

app/code/Magento/Tax/Test/Mftf/Data/TaxRateData.xml

@@ -117,4 +117,14 @@
         <data key="zip_is_range">0</data>
         <data key="rate">10</data>
     </entity>
+    <entity name="taxRateWithInvalidPostCodeLength" type="taxRate">
+        <data key="code" unique="suffix">Tax Rate </data>
+        <data key="tax_country_id">US</data>
+        <data key="tax_country">United States</data>
+        <data key="tax_region_id">12</data>
+        <data key="tax_region">California</data>
+        <data key="tax_postcode">12345678901</data>
+        <data key="zip_is_range">0</data>
+        <data key="rate">100.0000</data>
+    </entity>
 </entities>

app/code/Magento/Tax/Test/Mftf/Section/AdminTaxRateFormSection.xml

@@ -20,5 +20,6 @@
         <element name="rangeFrom" type="text" selector="#zip_from"/>
         <element name="rangeTo" type="text" selector="#zip_to"/>
         <element name="zipCode" type="input" selector="#tax_postcode"/>
+        <element name="fieldError" type="text" selector="//input[@name='{{fieldName}}']/following-sibling::label[@class='mage-error']" parameterized="true"/>
     </section>
 </sections>

app/code/Magento/Tax/Test/Mftf/Test/AdminCreateTaxRateInvalidPostcodeTestLength.xml

@@ -0,0 +1,37 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+ /**
+  * Copyright © Magento, Inc. All rights reserved.
+  * See COPYING.txt for license details.
+  */
+-->
+
+<tests xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+       xsi:noNamespaceSchemaLocation="urn:magento:mftf:Test/etc/testSchema.xsd">
+    <test name="AdminCreateTaxRateInvalidPostcodeTestLength">
+        <annotations>
+            <stories value="Create tax rate"/>
+            <title value="Create tax rate, invalid post code length"/>
+            <description value="Test log in to Create Tax Rate and Create Tax Rate with invalid post code length"/>
+            <testCaseId value="MC-18817"/>
+            <severity value="AVERAGE"/>
+            <group value="tax"/>
+            <group value="mtf_migrated"/>
+        </annotations>
+        <before>
+            <actionGroup ref="LoginAsAdmin" stepKey="loginAsAdmin"/>
+        </before>
+
+        <amOnPage url="{{AdminTaxRateGridPage.url}}" stepKey="goToTaxRateIndex1"/>
+        <waitForPageLoad stepKey="waitForTaxRateIndex1"/>
+        <!-- Create a tax rate for large postcodes -->
+        <click selector="{{AdminTaxRateGridSection.add}}" stepKey="clickAddNewTaxRateButton"/>
+        <fillField selector="{{AdminTaxRateFormSection.taxIdentifier}}" userInput="{{taxRateWithInvalidPostCodeLength.code}}" stepKey="fillRuleName"/>
+        <fillField selector="{{AdminTaxRateFormSection.zipCode}}" userInput="{{taxRateWithInvalidPostCodeLength.tax_postcode}}" stepKey="fillPostCode"/>
+        <selectOption selector="{{AdminTaxRateFormSection.country}}" userInput="{{taxRateWithInvalidPostCodeLength.tax_country}}" stepKey="selectCountry1"/>
+        <selectOption selector="{{AdminTaxRateFormSection.state}}" userInput="{{taxRateWithInvalidPostCodeLength.tax_region}}" stepKey="selectState" />
+        <fillField selector="{{AdminTaxRateFormSection.rate}}" userInput="{{taxRateWithInvalidPostCodeLength.rate}}" stepKey="fillRate"/>
+        <click selector="{{AdminTaxRateFormSection.save}}" stepKey="clickSave"/>
+        <see selector="{{AdminTaxRateFormSection.fieldError('tax_postcode')}}" userInput="Please enter less or equal than 10 symbols." stepKey="seeErrorMessage"/>
+    </test>
+</tests>