Quick fix to ignore a specific error (#25915).

pkg/analysis_server/test/services/correction/fix_test.dart

Index: pkg/analysis_server/test/services/correction/fix_test.dart
diff --git a/pkg/analysis_server/test/services/correction/fix_test.dart b/pkg/analysis_server/test/services/correction/fix_test.dart
index 853a4488837dafc316da747af9ec0f5dcc30426f..c69487ea5bc2bff57f1cee3335b99a47e0ac1894 100644
--- a/pkg/analysis_server/test/services/correction/fix_test.dart
+++ b/pkg/analysis_server/test/services/correction/fix_test.dart
@@ -252,6 +252,22 @@ class Test {
 ''');
   }
 
+  test_addIgnoreWarning() async {
+    resolveTestUnit('''
+main() {
+  int x = ''; //invalid_assignment
+}
+''');
+    await assertHasFix(
+        DartFixKind.IGNORE_ERROR,
+        '''
+main() {
+  //ignore: invalid_assignment
+  int x = ''; //invalid_assignment
+}
+''');
+  }
+
   test_addMissingParameter_function_positional_hasNamed() async {
     resolveTestUnit('''
 test({int a}) {}
@@ -473,6 +489,8 @@ main() {
       }
       if (error.message == message2) {
         List<Fix> fixes = await _computeFixes(error);
+        // remove ignore fix
+        fixes.removeWhere((Fix fix) => fix.kind == DartFixKind.IGNORE_ERROR);
         // has exactly one fix
         expect(fixes, hasLength(1));
         Fix fix = fixes[0];