MAGETWO-69922: #9139 Unable to set negative product's quantity fixes commit. #9770

 - Merge Pull Request #9770 from poongud/magento2:negative-product-qty
 - Merged commits:
   1. 0c691f4

Author: Oleksii Korshenko

app/code/Magento/CatalogInventory/Ui/DataProvider/Product/Form/Modifier/AdvancedInventory.php

@@ -213,7 +213,7 @@ private function prepareMeta()
                 'dataScope' => 'qty',
                 'validation' => [
                     'validate-number' => true,
-                    'validate-digits' => true,
+                    'validate-integer' => true,
                     'less-than-equals-to' => StockDataFilter::MAX_QTY_VALUE,
                 ],
                 'imports' => [

app/code/Magento/CatalogInventory/view/adminhtml/ui_component/product_form.xml

@@ -95,7 +95,7 @@
                         <item name="dataScope" xsi:type="string">quantity_and_stock_status.qty</item>
                         <item name="validation" xsi:type="array">
                             <item name="validate-number" xsi:type="boolean">true</item>
-                            <item name="validate-digits" xsi:type="boolean">true</item>
+                            <item name="validate-integer" xsi:type="boolean">true</item>
                             <item name="less-than-equals-to" xsi:type="number">99999999</item>
                         </item>
                         <item name="sortOrder" xsi:type="number">200</item>

app/code/Magento/CatalogInventory/view/adminhtml/web/js/components/qty-validator-changer.js

@@ -19,8 +19,7 @@ define([
         handleChanges: function (value) {
             var isDigits = value !== 1;
 
-            this.validation['validate-number'] = !isDigits;
-            this.validation['validate-digits'] = isDigits;
+            this.validation['validate-integer'] = isDigits;
             this.validation['less-than-equals-to'] = isDigits ? 99999999 : 99999999.9999;
             this.validate();
         }

app/code/Magento/Ui/view/base/web/js/lib/validation/rules.js

@@ -572,6 +572,15 @@ define([
             },
             $.mage.__('Please enter a valid number in this field.')
         ],
+        "validate-integer": [
+            function(value) {
+                return (
+                     utils.isEmptyNoTrim(value)
+                      || (!isNaN(utils.parseNumber(value)) && /^\s*-?\d*\s*$/.test(value))
+               );
+             },
+            $.mage.__('Please enter a valid integer in this field.')
+         ],
         "validate-number-range": [
             function(value, param) {
                 if (utils.isEmptyNoTrim(value)) {