[Tests] TypeWrappers/NFC: Add a tests to round-trip type wrappers in swift interfaces

Author: xedin

test/Serialization/type_wrapper_in_swiftinterface.swift

@@ -0,0 +1,95 @@
+// RUN: %empty-directory(%t/src)
+// RUN: %empty-directory(%t/sdk)
+// RUN: split-file %s %t/src
+
+/// Build the library.
+// RUN: %target-swift-frontend -emit-module %t/src/PublicModule.swift \
+// RUN:   -module-name PublicModule -swift-version 5 -enable-library-evolution \
+// RUN:   -emit-module-path %t/PublicModule.swiftmodule \
+// RUN:   -emit-module-interface-path %t/PublicModule.swiftinterface \
+// RUN:   -emit-private-module-interface-path %t/PublicModule.private.swiftinterface \
+// RUN:   -enable-experimental-feature TypeWrappers
+
+/// Verify swiftinterfaces.
+// RUN: %target-swift-typecheck-module-from-interface(%t/PublicModule.swiftinterface) -module-name PublicModule
+// RUN: %target-swift-typecheck-module-from-interface(%t/PublicModule.private.swiftinterface) -module-name PublicModule
+
+/// Test the client against the binary swiftmodule.
+// RUN: %target-swift-frontend -typecheck %t/src/Client.swift \
+// RUN:   -enable-experimental-feature TypeWrappers \
+// RUN:   -module-name Client -I %t
+
+/// Test the client against the private swiftinterface.
+// RUN: rm %t/PublicModule.swiftmodule
+// RUN: %target-swift-frontend -typecheck %t/src/Client.swift \
+// RUN:   -module-name Client -I %t \
+// RUN:   -enable-experimental-feature TypeWrappers
+
+/// Test the client against the public swiftinterface.
+// RUN: rm %t/PublicModule.private.swiftinterface
+// RUN: %target-swift-frontend -typecheck %t/src/Client.swift \
+// RUN:   -module-name Client -I %t \
+// RUN:   -enable-experimental-feature TypeWrappers
+
+//--- PublicModule.swift
+@typeWrapper
+public struct Wrapper<W, S> {
+  public init(for: W.Type, storage: S) {}
+
+  public subscript<V>(propertyKeyPath _: KeyPath<W, V>, storageKeyPath path: KeyPath<S, V>) -> V {
+    get { fatalError() }
+  }
+
+  public subscript<V>(propertyKeyPath _: KeyPath<W, V>, storageKeyPath path: WritableKeyPath<S, V>) -> V {
+    get { fatalError() }
+    set { }
+  }
+}
+
+@Wrapper
+public protocol Wrapped {}
+
+@Wrapper
+public struct MyWrappedType {
+  var x: Int = 0
+
+  public init() {}
+}
+
+@propertyWrapper
+public struct PropWrapper<T> {
+  typealias Wrapped = T
+
+  public var wrappedValue: T {
+    get { fatalError() }
+    set { value = newValue }
+  }
+
+  var value: T?
+
+  public init() {}
+
+  public init(wrappedValue: T) {
+    self.value = wrappedValue
+  }
+}
+
+//--- Client.swift
+
+import PublicModule
+
+@Wrapper
+final class S {
+  @PropWrapper var x: Int
+
+  required init() {}
+
+  required init(x: Int) {
+    self.x = x
+  }
+}
+
+let s = S()
+_ = s.$storage
+
+_ = MyWrappedType()