From bfc4e5048e495dccab7bb670a7b8773430ac189c Mon Sep 17 00:00:00 2001
From: Gabor Horvath <gaborh@apple.com>
Date: Fri, 28 Jun 2024 15:32:17 +0100
Subject: [PATCH] [cxx-interop] Add new tests for consuming shared foreign
 reference types

Check semantics for functions creating FRTs, and wrapping FRTs.
---
 ...struct-parameter-back-to-cxx-execution.cpp | 57 +++++++++++++++++--
 ...-not-supported-on-foreign-references.swift | 40 +++++++++++++
 2 files changed, 91 insertions(+), 6 deletions(-)
 create mode 100644 test/Interop/CxxToSwiftToCxx/consuming-not-supported-on-foreign-references.swift

diff --git a/test/Interop/CxxToSwiftToCxx/consuming-cxx-struct-parameter-back-to-cxx-execution.cpp b/test/Interop/CxxToSwiftToCxx/consuming-cxx-struct-parameter-back-to-cxx-execution.cpp
index 88105d62db56d..ce57d07d8be71 100644
--- a/test/Interop/CxxToSwiftToCxx/consuming-cxx-struct-parameter-back-to-cxx-execution.cpp
+++ b/test/Interop/CxxToSwiftToCxx/consuming-cxx-struct-parameter-back-to-cxx-execution.cpp
@@ -63,6 +63,8 @@ __attribute__((swift_attr("release:releaseShared")));
 inline void retainShared(SharedFRT *r) { puts("retainShared"); }
 inline void releaseShared(SharedFRT *r) { puts("releaseShared"); }
 
+inline SharedFRT* createSharedFRT() { return new SharedFRT(); }
+
 //--- module.modulemap
 module CxxTest {
     header "header.h"
@@ -89,20 +91,38 @@ public func consumeImmortalFRT(_ x: consuming ImmortalFRT) {
   print("immortal frt x \(x.x)")
 }
 
-public
-func consumeSharedFRT(_ x : consuming SharedFRT) {
+public func consumeSharedFRT(_ x : consuming SharedFRT) {
   print("consume shared frt x \(x.x)")
 }
 
-public
-func takeSharedFRT(_ x : SharedFRT) { print("take shared frt x \(x.x)") }
+public func takeSharedFRT(_ x : SharedFRT) {
+  print("take shared frt x \(x.x)")
+}
+
+public func genericConsumingFunc<T>(_ p: consuming T) {
+  print("generic consuming function")
+}
 
-public
-func returnSharedFRT(_ x : SharedFRT) -> SharedFRT {
+public func returnSharedFRT(_ x : SharedFRT) -> SharedFRT {
   print("return shared frt x \(x.x)")
   return x
 }
 
+public func returnSharedFRT2() -> SharedFRT {
+  return createSharedFRT()
+}
+
+public struct ValueWrapper {
+  let sharedFRT: SharedFRT
+  public init(_ x: SharedFRT) {
+    self.sharedFRT = x
+  }
+}
+
+public func consumeValueWrapper(_ x: consuming  ValueWrapper) {
+  print("return shared frt x \(x.sharedFRT.x)")
+}
+
 //--- use-swift-cxx-types.cpp
 
 #include "header.h"
@@ -160,6 +180,31 @@ int main() {
     SharedFRT *sfrtptr = UseCxx::returnSharedFRT(&sfrt);
     // CHECK-NEXT: retainShared
     // CHECK-NEXT: return shared frt x 2
+    SharedFRT *sfrtptr2 = UseCxx::returnSharedFRT2();
+    // No retain or release here.
+  }
+  {
+    SharedFRT sfrt;
+    sfrt.x = 4;
+    auto wrapper = UseCxx::ValueWrapper::init(&sfrt);
+    // consumeValueWrapper creates a defensive copy in the thunk.
+    UseCxx::consumeValueWrapper(wrapper);
+    // CHECK-NEXT: retainShared
+    // CHECK-NEXT: retainShared
+    // CHECK-NEXT: releaseShared
+    // CHECK-NEXT: return shared frt x 4
+    // CHECK-NEXT: releaseShared
+  }
+  {
+    SharedFRT sfrt;
+    sfrt.x = 4;
+    auto wrapper = UseCxx::ValueWrapper::init(&sfrt);
+    UseCxx::genericConsumingFunc(wrapper);
+    // CHECK-NEXT: retainShared
+    // CHECK-NEXT: retainShared
+    // CHECK-DAG: releaseShared
+    // CHECK-DAG: generic consuming function
+    // CHECK-NEXT: releaseShared
   }
   puts("EndOfTest");
 // CHECK-NEXT: EndOfTest
diff --git a/test/Interop/CxxToSwiftToCxx/consuming-not-supported-on-foreign-references.swift b/test/Interop/CxxToSwiftToCxx/consuming-not-supported-on-foreign-references.swift
new file mode 100644
index 0000000000000..01c26e6ff7f5d
--- /dev/null
+++ b/test/Interop/CxxToSwiftToCxx/consuming-not-supported-on-foreign-references.swift
@@ -0,0 +1,40 @@
+// RUN: %empty-directory(%t)
+// RUN: split-file %s %t
+
+// RUN: %target-interop-build-clangxx -std=c++20 -c %t/use-swift-cxx-types.cpp -I %t -o %t/swift-cxx-execution.o
+// RUN: not %target-interop-build-swift %t/use-cxx-types.swift -o %t/swift-cxx-execution -Xlinker %t/swift-cxx-execution.o -module-name UseCxx -Xfrontend -entry-point-function-name -Xfrontend swiftMain -I %t -O -Xfrontend -disable-availability-checking 2> %t/out
+
+// RUN: cat %t/out | %FileCheck %s
+
+//--- header.h
+
+class SharedFRT {
+public:
+    int x;
+} __attribute__((swift_attr("import_reference")))
+__attribute__((swift_attr("retain:retainShared")))
+__attribute__((swift_attr("release:releaseShared")));
+
+inline void retainShared(SharedFRT *r) { }
+inline void releaseShared(SharedFRT *r) { }
+
+//--- use-swift-cxx-types.cpp
+#include "header.h"
+
+int main() {}
+
+//--- module.modulemap
+module CxxTest {
+    header "header.h"
+    requires cplusplus
+}
+
+//--- use-cxx-types.swift
+import CxxTest
+
+public func consumeSharedFRT(_ x: consuming SharedFRT) {}
+public func takeSharedFRT(_ x: SharedFRT) {
+    consumeSharedFRT(consume x)
+    // CHECK: error: 'consume' applied to value that the compiler does not support. This is a compiler bug. Please file a bug with a small example of the bug
+    x.x = 10
+}