2 files changed, 12 insertions, 3 deletions

diff --git a/src/intercopycontext.cpp b/src/intercopycontext.cpp
index 0ccd619..4be1883 100644
--- a/src/intercopycontext.cpp
+++ b/src/intercopycontext.cpp
@@ -494,8 +494,12 @@ void InterCopyContext::interCopyKeyValuePair() const
             *std::format_to(_valPath, "{}[U:{}]", name, _key) = 0;
         } else if (luaW_type(L1, _key_i) == LuaType::BOOLEAN) {
             int const _key{ lua_toboolean(L1, _key_i) };
-            _valPath = static_cast<char*>(alloca(name.size() + 8)); // +8 for [], 'false' and terminating 0
+            _valPath = static_cast<char*>(alloca(name.size() + 8)); // +8 for [false] and terminating 0
             *std::format_to(_valPath, "{}[{}]", name, _key ? "true" : "false") = 0;
+        } else if (luaW_type(L1, _key_i) == LuaType::USERDATA) {
+            // I don't want to invoke tostring on the userdata to get its name
+            _valPath = static_cast<char*>(alloca(name.size() + 11)); // +11 for [U:<FULL>] and terminating 0
+            *std::format_to(_valPath, "{}[U:<FULL>]", name) = 0;
         }
     }
 
diff --git a/unit_tests/scripts/misc/verbose_errors.lua b/unit_tests/scripts/misc/verbose_errors.lua
index b38bf4c..8127980 100644
--- a/unit_tests/scripts/misc/verbose_errors.lua
+++ b/unit_tests/scripts/misc/verbose_errors.lua
@@ -21,9 +21,13 @@ local do_test = function(key_)
                 local x, y = string.find(e, "arg#2.subtable[" .. key_ .. "].ud", 1, true)
                 assert(x and y, "got " .. e)
         elseif t_key == "userdata" then
-                local t_name
+                -- light userdata results in "userdata: <some uppercase hex value>"
+                local stringified_key = tostring(key_)
+                local hex = string.match(stringified_key, "userdata: (%x+)")
+                -- full userdata results in something else
+                local t_name = hex and ("0x" .. string.lower(hex)) or "<FULL>"
                 -- light userdata is formatted by std::format, where the pointer is written as a lowercase hex literal
-                local expected = "arg#2.subtable[U:0x" .. string.lower(string.match(tostring(key_), "userdata: (%x+)")) .. "].ud"
+                local expected = "arg#2.subtable[U:" .. t_name .. "].ud"
                 -- expecting an error about arg#2.subtable[U:0x<some hex value>].ud
                 local x, y = string.find(e, expected, 1, true)
                 assert(x and y, "expecting " .. expected .. " got " .. e)
@@ -36,3 +40,4 @@ do_test(false)
 do_test(42)
 do_test(42.44)
 do_test(lanes.null)
+do_test(l)