Add test for as with typesafety

Author: filipsajdak

regression-tests/mixed-as-with-typesafety.cpp2

@@ -0,0 +1,32 @@
+void throw_error(CPP2_MESSAGE_PARAM msg CPP2_SOURCE_LOCATION_PARAM) {
+    throw std::runtime_error(std::string("Type safety exception: ") + msg);
+}
+
+make_throwable: (inout cg : cpp2::contract_group) -> _ = {
+    h := cg.get_handler();
+    sh := :(pcg : *cpp2::contract_group) = {
+        pcg*.set_handler(h$);
+    };
+    cg.set_handler(throw_error);
+    return std::unique_ptr<cpp2::contract_group, decltype(sh)>(cg&, sh);
+}
+
+void expect_no_throw(auto&& fun) try {
+    fun();
+} catch(std::exception const& e) {
+    std::cout << e.what() << std::endl;
+} catch(...) {
+    std::cout << "Unknown exception!" << std::endl;
+}
+
+main: () = {
+    o : std::optional<int> = ();
+
+    (_ := make_throwable(cpp2::type_safety)) {
+        expect_no_throw( :() = {
+            std::cout << (o$ as int) << std::endl; // that will throw
+        });
+    }
+
+    std::cout << (o as int) << std::endl; // that will terminate
+}

regression-tests/test-results/apple-clang-14-c++2b/mixed-as-with-typesafety.cpp.execution

@@ -0,0 +1,3 @@
+Type safety exception: 'as' cast failed for 'std::optional'
+Type safety violation: 'as' cast failed for 'std::optional'
+libc++abi: terminating

regression-tests/test-results/mixed-as-with-typesafety.cpp

@@ -0,0 +1,63 @@
+
+
+//=== Cpp2 type declarations ====================================================
+
+
+#include "cpp2util.h"
+
+#line 1 "mixed-as-with-typesafety.cpp2"
+
+
+//=== Cpp2 type definitions and function declarations ===========================
+
+#line 1 "mixed-as-with-typesafety.cpp2"
+void throw_error(CPP2_MESSAGE_PARAM msg CPP2_SOURCE_LOCATION_PARAM) {
+    throw std::runtime_error(std::string("Type safety exception: ") + msg);
+}
+
+#line 5 "mixed-as-with-typesafety.cpp2"
+[[nodiscard]] auto make_throwable(cpp2::contract_group& cg) -> auto;
+#line 13 "mixed-as-with-typesafety.cpp2"
+
+void expect_no_throw(auto&& fun) try {
+    fun();
+} catch(std::exception const& e) {
+    std::cout << e.what() << std::endl;
+} catch(...) {
+    std::cout << "Unknown exception!" << std::endl;
+}
+
+auto main() -> int;
+
+//=== Cpp2 function definitions =================================================
+
+#line 1 "mixed-as-with-typesafety.cpp2"
+
+#line 5 "mixed-as-with-typesafety.cpp2"
+[[nodiscard]] auto make_throwable(cpp2::contract_group& cg) -> auto{
+    auto h {CPP2_UFCS(get_handler)(cg)}; 
+    auto sh {[_0 = cpp2::move(h)](cpp2::contract_group* pcg) mutable -> void{
+        CPP2_UFCS(set_handler)((*cpp2::impl::assert_not_null(pcg)), _0);
+    }}; 
+    CPP2_UFCS(set_handler)(cg, throw_error);
+    return std::unique_ptr<cpp2::contract_group,decltype(sh)>(&cg, cpp2::move(sh)); 
+}
+
+#line 22 "mixed-as-with-typesafety.cpp2"
+auto main() -> int{
+    std::optional<int> o {}; 
+{
+[[maybe_unused]] auto const& unnamed_param_1{make_throwable(cpp2::type_safety)};
+
+#line 25 "mixed-as-with-typesafety.cpp2"
+    {
+        expect_no_throw([_0 = o]() mutable -> void{
+            std::cout << (cpp2::impl::as_<int>(_0)) << std::endl;// that will throw
+        });
+    }
+}
+
+#line 31 "mixed-as-with-typesafety.cpp2"
+    std::cout << (cpp2::impl::as_<int>(cpp2::move(o))) << std::endl;// that will terminate
+}
+

regression-tests/test-results/mixed-as-with-typesafety.cpp2.output

@@ -0,0 +1,2 @@
+mixed-as-with-typesafety.cpp2... ok (mixed Cpp1/Cpp2, Cpp2 code passes safety checks)
+