fix(mask): Correct auto-fill handling with literals

When the browser auto-fills a masked input field, it may include literal characters
as part of the filled value. The previous implementation did not correctly handle
such cases, leading to incorrect parsing and display of the input value.

Author: rkaraivanov

src/components/mask-input/mask-input-base.ts

@@ -119,8 +119,9 @@ export abstract class IgcMaskInputBaseComponent extends IgcInputBaseComponent {
 
       // Potential browser auto-fill behavior
       case undefined:
+      case '':
         return this._updateInput(
-          value.substring(start, this._inputSelection.end),
+          this._parser.parse(value.substring(start, this._inputSelection.end)),
           {
             start,
             end: this._inputSelection.end,

src/components/mask-input/mask-input.spec.ts

@@ -622,6 +622,23 @@ describe('Masked input', () => {
       expect(element.value).to.equal('xxba');
       expect(input.value).to.equal(parser.apply(element.value));
     });
+
+    it('auto-fill behavior for mask with literals', async () => {
+      element.mask = '(+35\\9) CCC-CCC';
+
+      await elementUpdated(element);
+      syncParser();
+
+      simulateInput(input, {
+        inputType: undefined, // auto-fill event
+        skipValueProperty: false,
+        value: '(+359) 123-456',
+      });
+      await elementUpdated(element);
+
+      expect(element.value).to.equal('123456');
+      expect(input.value).to.equal(parser.apply(element.value));
+    });
   });
 
   describe('Form integration', () => {