#2956. Update and rename existing tests for type void (#2978)

Update and rename existing tests for type `void`. Part 1 & 2.

Language/Types/Type_Void/permitted_use_A13_t01.dart

@@ -0,0 +1,34 @@
+// Copyright (c) 2011, 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 In support of the notion that the value of an expression with
+/// static type `void` should be discarded, such objects can only be used in
+/// specific situations: The occurrence of an expression of type `void` is a
+/// compile-time error unless it is permitted according to one of the following
+/// rules.
+/// ...
+/// - An actual parameter expression corresponding to a formal parameter whose
+///   statically known type annotation is `void` may have type `void`.
+///
+/// @description Checks that it is not an error to declare a function with a
+/// formal parameter which has a type `void`.
+/// @author iefremov
+
+void topLevelFunction(void v) {}
+
+class C {
+  static void staticMethod(void v) {}
+   void instanceMethod(void v) {}
+}
+
+main() {
+  localFunction(void a) {};
+  var f = (void v) {};
+
+  topLevelFunction(null);
+  C.staticMethod(0);
+  C().instanceMethod(Object());
+  localFunction("");
+  f(42 as dynamic);
+}

Language/Types/Type_Void/permitted_use_A13_t02.dart

@@ -0,0 +1,30 @@
+// Copyright (c) 2024, 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 In support of the notion that the value of an expression with
+/// static type `void` should be discarded, such objects can only be used in
+/// specific situations: The occurrence of an expression of type `void` is a
+/// compile-time error unless it is permitted according to one of the following
+/// rules.
+/// ...
+/// - An actual parameter expression corresponding to a formal parameter whose
+///   statically known type annotation is `void` may have type `void`.
+///
+/// @description Checks that it is not an error to declare a record with a
+/// parameter which has a type `void`.
+/// @author [email protected]
+
+typedef R1 = (void v,);
+typedef R2 = ({void v});
+
+main() {
+  R1 r1 = (1,);
+  R2 r2 = (v: 2);
+  (void v,) r3 = (3,);
+  ({void v}) r4 = (v: 4);
+  print(r1);
+  print(r2);
+  print(r3);
+  print(r4);
+}

Language/Types/Type_Void/permitted_use_A13_t03.dart

@@ -0,0 +1,23 @@
+// Copyright (c) 2024, 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 In support of the notion that the value of an expression with
+/// static type `void` should be discarded, such objects can only be used in
+/// specific situations: The occurrence of an expression of type `void` is a
+/// compile-time error unless it is permitted according to one of the following
+/// rules.
+/// ...
+/// - An actual parameter expression corresponding to a formal parameter whose
+///   statically known type annotation is `void` may have type `void`.
+///
+/// @description Checks that it is not an error to declare an extension type
+/// with a representation type `void`.
+/// @author [email protected]
+
+extension type ET(void v) {}
+
+main() {
+  ET et = ET(42);
+  print(et);
+}

Language/Types/Type_Void/type_void_A01_t01.dart

@@ -0,0 +1,17 @@
+// Copyright (c) 2011, 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 The special type `void` is used to indicate that the value of an
+/// expression is meaningless and intended to be discarded.
+///
+/// @description Checks that specifying `void` as a function's parameter type
+/// (without the parameter name) causes a syntax error.
+/// @author iefremov
+
+main() {
+  f(void) {};
+//      ^
+// [analyzer] unspecified
+// [cfe] unspecified
+}