dart-lang#1400. Add object pattern tests for extension types

LanguageFeatures/Extension-types/static_analysis_extension_types_A32_t01.dart

@@ -0,0 +1,38 @@
+// Copyright (c) 2023, 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.
+
+/// @assertion An extension type V (which may include actual type arguments) can
+/// be used in an object pattern (e.g., case V(): ... where V is an extension
+/// type). Exhaustiveness analysis will treat such patterns as if they had been
+/// an object pattern matching the extension type erasure of V.
+///
+/// @description Check that an extension type can be used in an object pattern
+/// @author sgrekhov22@gmail.com
+
+// SharedOptions=--enable-experiment=inline-class
+
+import "../../Utils/expect.dart";
+
+class C {
+  int x;
+  C(this.x);
+}
+
+extension type ET1(C id) {}
+extension type ET2(C id) implements C {}
+
+main() {
+  var ET1() = ET1(C(0));
+  var ET2(x: v1) = ET2(C(1));
+  Expect.equals(1, v1);
+
+  var C(x: v2) = ET2(C(2));
+  Expect.equals(2, v2);
+
+  var ET1(id: v3) = ET1(C(3));
+  Expect.equals(3, v3.x);
+
+  var ET2(id: v4) = ET2(C(4));
+  Expect.equals(4, v4.x);
+}

LanguageFeatures/Extension-types/static_analysis_extension_types_A32_t02.dart

@@ -0,0 +1,39 @@
+// Copyright (c) 2023, 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.
+
+/// @assertion An extension type V (which may include actual type arguments) can
+/// be used in an object pattern (e.g., case V(): ... where V is an extension
+/// type). Exhaustiveness analysis will treat such patterns as if they had been
+/// an object pattern matching the extension type erasure of V.
+///
+/// @description Check that an extension type can be used in an object pattern.
+/// Test generics
+/// @author sgrekhov22@gmail.com
+
+// SharedOptions=--enable-experiment=inline-class
+
+import "../../Utils/expect.dart";
+
+class C<T> {
+  T x;
+  C(this.x);
+}
+
+extension type ET1<T>(C<T> id) {}
+extension type ET2<T>(C<T> id) implements C<T> {}
+
+main() {
+  var ET1<num>() = ET1(C(3.14));
+  var ET2<int>(x: v1) = ET2<int>(C(1));
+  Expect.equals(1, v1);
+
+  var C<String>(x: v2) = ET2<String>(C<String>("2"));
+  Expect.equals("2", v2);
+
+  var ET1<String>(id: v3) = ET1(C<String>("3"));
+  Expect.equals("3", v3.x);
+
+  var ET2<int>(id: v4) = ET2<int>(C(4));
+  Expect.equals(4, v4.x);
+}

LanguageFeatures/Extension-types/static_analysis_extension_types_A32_t03.dart

@@ -0,0 +1,50 @@
+// Copyright (c) 2023, 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.
+
+/// @assertion An extension type V (which may include actual type arguments) can
+/// be used in an object pattern (e.g., case V(): ... where V is an extension
+/// type). Exhaustiveness analysis will treat such patterns as if they had been
+/// an object pattern matching the extension type erasure of V.
+///
+/// @description Check that an extension type erasure is not used in an object
+/// pattern outside of switch statements and expressions
+/// @author sgrekhov22@gmail.com
+
+// SharedOptions=--enable-experiment=inline-class
+
+class C {
+  int x;
+  C(this.x);
+}
+
+extension type ET1(C id) {}
+extension type ET2(C id) {}
+extension type ET3(C id) implements C {}
+
+main() {
+  var C(x: v1) = ET1(C(1));
+//    ^^^^^^^^
+// [analyzer] unspecified
+// [cfe] unspecified
+  var ET1(x: v2) = ET1(C(2));
+//        ^
+// [analyzer] unspecified
+// [cfe] unspecified
+  var ET1() = C(42);
+//    ^^^^^
+// [analyzer] unspecified
+// [cfe] unspecified
+  var ET1() = ET2(C(42));
+//    ^^^^^
+// [analyzer] unspecified
+// [cfe] unspecified
+  var ET3(x: v3) = C(42);
+//    ^^^^^^^^^^
+// [analyzer] unspecified
+// [cfe] unspecified
+  var ET3(x: v4) = ET1(C(42));
+//    ^^^^^^^^^^
+// [analyzer] unspecified
+// [cfe] unspecified
+}