From 20e1c69f58ba8955e2c7a99303145c68a9ea8500 Mon Sep 17 00:00:00 2001
From: Peter Ludemann <peter.ludemann@gmail.com>
Date: Tue, 6 Jan 2026 18:07:16 -0800
Subject: [PATCH] Add exception smoke tests, generalize PlUnknownError

---
 SWI-cpp2.cpp | 10 +++++++---
 SWI-cpp2.h   |  2 ++
 test_cpp.cpp |  8 ++++++++
 test_cpp.pl  |  5 +++++
 4 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/SWI-cpp2.cpp b/SWI-cpp2.cpp
index 5293977..8cd5997 100644
--- a/SWI-cpp2.cpp
+++ b/SWI-cpp2.cpp
@@ -267,11 +267,15 @@ PlResourceError(const std::string& resource)
 _SWI_CPP2_CPP_inline
 PlException
 PlUnknownError(const std::string& description)
-{ // For PlWrap()
-  return PlGeneralError(PlCompound("unknown_error",
-                                   PlTermv(PlTerm_atom(description))));
+{ return PlUnknownError(PlTerm_atom(description));
 }
 
+_SWI_CPP2_CPP_inline
+PlException
+PlUnknownError(PlTerm description)
+{  return PlGeneralError(PlCompound("unknown_error",
+                                    PlTermv(description)));
+}
 
 
 
diff --git a/SWI-cpp2.h b/SWI-cpp2.h
index 47c4db1..2ed7b5e 100644
--- a/SWI-cpp2.h
+++ b/SWI-cpp2.h
@@ -1306,6 +1306,8 @@ PlException PlResourceError(const std::string& resource);
 
 PlException PlUnknownError(const std::string& description);
 
+PlException PlUnknownError(PlTerm description);
+
 void PlWrap_fail(qid_t qid);
 
 template<typename C_t> C_t
diff --git a/test_cpp.cpp b/test_cpp.cpp
index e7f1b14..0a4dea5 100644
--- a/test_cpp.cpp
+++ b/test_cpp.cpp
@@ -114,6 +114,14 @@ PREDICATE(hello, 2)
   return A2.unify_string(buffer.str());
 }
 
+PREDICATE(helloex, 0)
+{ throw PlUnknownError("an exception");
+}
+
+PREDICATE(helloex, 1)
+{ throw PlUnknownError(A1);
+}
+
 PREDICATE(hello2, 2)
 { PlAtom atom_a1(A1.as_atom());
   std::stringstream buffer;
diff --git a/test_cpp.pl b/test_cpp.pl
index 8e0a5a5..a94d6ab 100644
--- a/test_cpp.pl
+++ b/test_cpp.pl
@@ -92,6 +92,11 @@
     % hello :- write('hello hello hello')
     with_output_to(string(Out), hello).
 
+test(helloex, error(unknown_error('an exception'))) :-
+    helloex.
+test(helloex, error(unknown_error(foo(bar)))) :-
+    helloex(foo(bar)).
+
 test(hello, Out == "Hello WORLD\nHello WORLD\nHello WORLD\nHello WORLD\nHello WORLD\n") :-
     hello("WORLD", Out).
 test(hello, error(representation_error(encoding))) :-