[tests] Dot Shorthands: .call() tests.

Adding tests for calling .call() on the dot shorthand getters/fields.

Bug: #57038
Change-Id: Ibdacd2bb9feba617f96996dd467328dbdb55c7b6
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/417904
Reviewed-by: Erik Ernst <[email protected]>

Author: kallentu

tests/language/dot_shorthands/simple/call_error_test.dart

@@ -0,0 +1,26 @@
+// Copyright (c) 2025, 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.
+
+// `id()` calls the `call()` method of the type of `id` if `id` is a getter or
+// field. It's a compile-time error if that `call` method does not exist.
+
+// SharedOptions=--enable-experiment=dot-shorthands
+
+class C {
+  const C();
+  static C get id1 => const C();
+  static C id2 = const C();
+}
+
+void main() {
+  C c1 = .id1();
+  // ^
+  // [analyzer] unspecified
+  // [cfe] unspecified
+
+  C c2 = .id2();
+  // ^
+  // [analyzer] unspecified
+  // [cfe] unspecified
+}

tests/language/dot_shorthands/simple/call_test.dart

@@ -0,0 +1,21 @@
+// Copyright (c) 2025, 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.
+
+// `id()` calls the `call()` method of the type of `id` if `id` is a getter or
+// field.
+
+// SharedOptions=--enable-experiment=dot-shorthands
+
+class C {
+  const C();
+  static C get id1 => const C();
+  static C id2 = const C();
+
+  C call() => const C();
+}
+
+void main() {
+  C c1 = .id1();
+  C c2 = .id2();
+}