Missing @required arg quick fix improvements.

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 57ff0c67387c3ee180f65cba8bfe05806d2a09a0..ecbd8803191473ccc177c3bb7f5e759350f43c3f 100644
--- a/pkg/analysis_server/test/services/correction/fix_test.dart
+++ b/pkg/analysis_server/test/services/correction/fix_test.dart
@@ -477,6 +477,48 @@ main() {
 ''');
   }
 
+  test_addMissingRequiredArg_multiple_2() async {
+    _addMetaPackageSource();
+
+    await resolveTestUnit('''
+import 'package:meta/meta.dart';
+
+test({@required int a, @required int bcd}) {}
+main() {
+  test();
+}
+''');
+
+    // For now we expect one error per missing arg (dartbug.com/28830).
+    List<AnalysisError> errors = await _computeErrors();
+    expect(errors, hasLength(2));
+
+    List<AnalysisError> filteredErrors = errors
+        .where((e) => e.message == "The parameter 'a' is required.")
+        .toList();
+    expect(filteredErrors, hasLength(1));
+
+    List<Fix> fixes = await _computeFixes(filteredErrors.first);
+
+    List<Fix> filteredFixes = fixes
+        .where((fix) => fix.change.message == "Add required argument 'a'")
+        .toList();
+    expect(filteredFixes, hasLength(1));
+    change = filteredFixes.first.change;
+    resultCode = SourceEdit.applySequence(testCode, change.edits[0].edits);
+    // verify
+    expect(
+        resultCode,
+        '''
+import 'package:meta/meta.dart';
+
+test({@required int a, @required int bcd}) {}
+main() {
+  test(a: null);
+}
+''');
+  }
+
   test_addMissingRequiredArg_single() async {
     _addMetaPackageSource();
 
@@ -523,6 +565,29 @@ main() {
 ''');
   }
 
+  test_addMissingRequiredArg_single_with_details() async {
+    _addMetaPackageSource();
+
+    await resolveTestUnit('''
+import 'package:meta/meta.dart';
+
+test({@Required("Really who doesn't need an abc?") int abc}) {}
+main() {
+  test();
+}
+''');
+    await assertHasFix(
+        DartFixKind.ADD_MISSING_REQUIRED_ARGUMENT,
+        '''
+import 'package:meta/meta.dart';
+
+test({@Required("Really who doesn't need an abc?") int abc}) {}
+main() {
+  test(abc: null);
+}
+''');
+  }
+
   test_addSync_asyncFor() async {
     await resolveTestUnit('''
 import 'dart:async';
@@ -5434,7 +5499,10 @@ main() {
   }
 
   void _addMetaPackageSource() {
-    addPackageSource('meta', 'meta.dart', r'''
+    addPackageSource(
+        'meta',
+        'meta.dart',
+        r'''
 library meta;
 
 const Required required = const Required();