Recognize LuaJIT TCDATA type to generate correct panic message.

Relates to #127
Should be fixed in a next major release by adding support of TCDATA type.

4 files changed, 35 insertions, 0 deletions

diff --git a/src/ffi/lua.rs b/src/ffi/lua.rs
index 12ec1cc..f96b989 100644
--- a/src/ffi/lua.rs
+++ b/src/ffi/lua.rs
@@ -101,6 +101,10 @@ pub const LUA_TFUNCTION: c_int = 6;
 pub const LUA_TUSERDATA: c_int = 7;
 pub const LUA_TTHREAD: c_int = 8;
 
+// Type produced by LuaJIT FFI module
+#[cfg(feature = "luajit")]
+pub const LUA_TCDATA: c_int = 10;
+
 #[cfg(feature = "lua54")]
 pub const LUA_NUMTYPES: c_int = 9;
 #[cfg(any(feature = "lua53", feature = "lua52"))]
diff --git a/src/ffi/mod.rs b/src/ffi/mod.rs
index c166ca6..0f49697 100644
--- a/src/ffi/mod.rs
+++ b/src/ffi/mod.rs
@@ -236,6 +236,9 @@ pub use self::lua::LUA_ERRGCMM;
 #[cfg(any(feature = "lua51", feature = "luajit"))]
 pub use self::lua::{LUA_ENVIRONINDEX, LUA_GLOBALSINDEX};
 
+#[cfg(feature = "luajit")]
+pub use self::lua::LUA_TCDATA;
+
 // constants from lauxlib.h
 pub use self::lauxlib::{LUA_ERRFILE, LUA_NOREF, LUA_REFNIL};
 
diff --git a/src/lua.rs b/src/lua.rs
index a768248..0138de7 100644
--- a/src/lua.rs
+++ b/src/lua.rs
@@ -1988,6 +1988,13 @@ impl Lua {
 
             ffi::LUA_TTHREAD => Value::Thread(Thread(self.pop_ref())),
 
+            #[cfg(feature = "luajit")]
+            ffi::LUA_TCDATA => {
+                ffi::lua_pop(state, 1);
+                // TODO: Fix this in a next major release
+                panic!("cdata objects cannot be handled by mlua yet");
+            }
+
             _ => mlua_panic!("LUA_TNONE in pop_value"),
         }
     }
diff --git a/tests/tests.rs b/tests/tests.rs
index 95c41ad..4b92d4f 100644
--- a/tests/tests.rs
+++ b/tests/tests.rs
@@ -1256,3 +1256,24 @@ fn test_warnings() -> Result<()> {
 
     Ok(())
 }
+
+#[test]
+#[cfg(feature = "luajit")]
+#[should_panic]
+fn test_luajit_cdata() {
+    let lua = unsafe { Lua::unsafe_new() };
+    let _v: Result<Value> = lua
+        .load(
+            r#"
+        local ffi = require("ffi")
+        ffi.cdef[[
+            void *malloc(size_t size);
+            void free(void *ptr);
+        ]]
+        local ptr = ffi.C.malloc(1)
+        ffi.C.free(ptr)
+        return ptr
+    "#,
+        )
+        .eval();
+}