lint rules: Migrate tests for type_init_formals

Change-Id: I409a639518dd165e4f422eef664fda7601b2e75c
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/398820
Reviewed-by: Phil Quitslund <pquitslund@google.com>
Auto-Submit: Samuel Rawlins <srawlins@google.com>
Commit-Queue: Phil Quitslund <pquitslund@google.com>
diff --git a/pkg/linter/test/rules/type_init_formals_test.dart b/pkg/linter/test/rules/type_init_formals_test.dart
index 97394ad..93e8d79 100644
--- a/pkg/linter/test/rules/type_init_formals_test.dart
+++ b/pkg/linter/test/rules/type_init_formals_test.dart
@@ -88,4 +88,43 @@
       lint(66, 7),
     ]);
   }
+
+  test_typed_fieldIsDynamic() async {
+    await assertNoDiagnostics(r'''
+class C {
+  var x;
+  C(int this.x);
+}
+''');
+  }
+
+  test_typed_sameAsField() async {
+    await assertDiagnostics(r'''
+class C {
+  int x;
+  C(int this.x);
+}
+''', [
+      lint(23, 3),
+    ]);
+  }
+
+  test_typed_subtypeOfField() async {
+    await assertNoDiagnostics(r'''
+class C {
+  num x;
+  C.i(int this.x);
+  C.d(double this.x);
+}
+''');
+  }
+
+  test_untyped() async {
+    await assertNoDiagnostics(r'''
+class C {
+  int x;
+  C(this.x);
+}
+''');
+  }
 }
diff --git a/pkg/linter/test_data/rules/type_init_formals.dart b/pkg/linter/test_data/rules/type_init_formals.dart
deleted file mode 100644
index 12681a8..0000000
--- a/pkg/linter/test_data/rules/type_init_formals.dart
+++ /dev/null
@@ -1,25 +0,0 @@
-// Copyright (c) 2015, the Dart project authors. Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-class Good {
-  String name;
-  Good(this.name); // OK
-}
-
-class Bad {
-  String name;
-  Bad(String this.name); //LINT [7:6]
-}
-
-class Good2 {
-  num a;
-  Good2.i(int this.a); // OK
-  Good2.d(double this.a); // OK
-}
-
-class Good3 {
-  var a;
-  Good3(int this.a); // OK
-}
-