[tests] Enum shorthands - Import prefixes.

Testing that enum shorthands work even with import prefixes of declarations.

Bug: #57038
Change-Id: I8026f062a2b405d4f92efff7abad1a03fa229eda
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/402425
Commit-Queue: Kallen Tu <[email protected]>
Reviewed-by: Erik Ernst <[email protected]>

Author: kallentu

tests/language/enum_shorthands/multiple/import_prefix_test.dart

@@ -0,0 +1,20 @@
+// 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.
+
+// Contexts with a prefix import should still work with enum shorthands.
+
+// SharedOptions=--enable-experiment=enum-shorthands
+
+import '../enum_shorthand_helper.dart' as prefix;
+
+void main() {
+  prefix.Integer integer = .one;
+  const prefix.Integer constInteger = .constOne;
+
+  // Nested
+  prefix.ConstructorClass ctorMemberCtor = .staticMember(.ctor(.named(x: 1)));
+
+  // Selector chain
+  prefix.StaticMember memberMixed2 = .member().field.method();
+}