Add fix for missing @required params.

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 d6bd2db659c3a682a8e929ed8b544a6d3f96e969..57ff0c67387c3ee180f65cba8bfe05806d2a09a0 100644
--- a/pkg/analysis_server/test/services/correction/fix_test.dart
+++ b/pkg/analysis_server/test/services/correction/fix_test.dart
@@ -427,6 +427,102 @@ class A {
 ''');
   }
 
+  test_addMissingRequiredArg_cons_single() async {
+    _addMetaPackageSource();
+
+    await resolveTestUnit('''
+import 'package:meta/meta.dart';
+
+class A {
+  A({@required int a}) {}
+}
+main() {
+  A a = new A();
+}
+''');
+    await assertHasFix(
+        DartFixKind.ADD_MISSING_REQUIRED_ARGUMENT,
+        '''
+import 'package:meta/meta.dart';
+
+class A {
+  A({@required int a}) {}
+}
+main() {
+  A a = new A(a: null);
+}
+''');
+  }
+
+  test_addMissingRequiredArg_multiple() async {
+    _addMetaPackageSource();
+
+    await resolveTestUnit('''
+import 'package:meta/meta.dart';
+
+test({@required int a, @required int bcd}) {}
+main() {
+  test(a: 3);
+}
+''');
+    await assertHasFix(
+        DartFixKind.ADD_MISSING_REQUIRED_ARGUMENT,
+        '''
+import 'package:meta/meta.dart';
+
+test({@required int a, @required int bcd}) {}
+main() {
+  test(a: 3, bcd: null);
+}
+''');
+  }
+
+  test_addMissingRequiredArg_single() async {
+    _addMetaPackageSource();
+
+    await resolveTestUnit('''
+import 'package:meta/meta.dart';
+
+test({@required int abc}) {}
+main() {
+  test();
+}
+''');
+    await assertHasFix(
+        DartFixKind.ADD_MISSING_REQUIRED_ARGUMENT,
+        '''
+import 'package:meta/meta.dart';
+
+test({@required int abc}) {}
+main() {
+  test(abc: null);
+}
+''');
+  }
+
+  test_addMissingRequiredArg_single_normal() async {
+    _addMetaPackageSource();
+
+    await resolveTestUnit('''
+import 'package:meta/meta.dart';
+
+test(String x, {@required int abc}) {}
+main() {
+  test("foo");
+}
+''');
+    await assertHasFix(
+        DartFixKind.ADD_MISSING_REQUIRED_ARGUMENT,
+        '''
+import 'package:meta/meta.dart';
+
+test(String x, {@required int abc}) {}
+main() {
+  test("foo", abc: null);
+}
+''');
+  }
+
   test_addSync_asyncFor() async {
     await resolveTestUnit('''
 import 'dart:async';
@@ -5336,6 +5432,19 @@ main() {
 }
 ''');
   }
+
+  void _addMetaPackageSource() {
+    addPackageSource('meta', 'meta.dart', r'''
+library meta;
+
+const Required required = const Required();
+
+class Required {
+  final String reason;
+  const Required([this.reason]);
+}
+''');
+  }
 }
 
 @reflectiveTest