A lot of corner case bugfixes

1 files changed, 17 insertions, 23 deletions

diff --git a/src/util.rs b/src/util.rs
index d043248..32161c0 100644
--- a/src/util.rs
+++ b/src/util.rs
@@ -113,11 +113,10 @@ where
 }
 
 // If the return code indicates an error, pops the error off of the stack and
-// returns Err. If the error was actually a rust panic, clears the current lua
-// stack and panics.  If the error on the top of the stack is actually a
-// WrappedError::Error, just returns it.  If the error on the top of the stack
-// is a WrappedError::Panic, clears the rust stack and resumes the panic,
-// otherwise interprets the error as the appropriate lua error.
+// returns Err. If the error is actually a WrappedPaic, clears the current lua
+// stack continues the panic.  If the error on the top of the stack is actually
+// a WrappedError, just returns it.  Otherwise, interprets the error as the
+// appropriate lua error.
 pub unsafe fn handle_error(state: *mut ffi::lua_State, err: c_int) -> LuaResult<()> {
     if err == ffi::LUA_OK || err == ffi::LUA_YIELD {
         Ok(())
@@ -126,12 +125,19 @@ pub unsafe fn handle_error(state: *mut ffi::lua_State, err: c_int) -> LuaResult<
             Err(pop_wrapped_error(state).unwrap())
 
         } else if is_wrapped_panic(state, -1) {
-            resume_unwind(pop_wrapped_panic(state).unwrap())
+            let userdata = ffi::lua_touserdata(state, -1);
+            let panic = &mut *(userdata as *mut WrappedPanic);
+            resume_unwind(panic.0.take().expect(
+                "internal error: panic was resumed twice",
+            ))
 
         } else {
             let err_string =
                 if let Some(s) = ffi::lua_tolstring(state, -1, ptr::null_mut()).as_ref() {
-                    CStr::from_ptr(s).to_str().unwrap().to_owned()
+                    CStr::from_ptr(s)
+                        .to_str()
+                        .unwrap_or_else(|_| "<unprintable error>")
+                        .to_owned()
                 } else {
                     "<unprintable error>".to_owned()
                 };
@@ -227,7 +233,7 @@ pub unsafe fn pcall_with_traceback(
             ffi::luaL_traceback(state, state, ptr::null(), 0);
             let traceback = CStr::from_ptr(ffi::lua_tolstring(state, -1, ptr::null_mut()))
                 .to_str()
-                .unwrap()
+                .unwrap_or_else(|_| "<could not capture traceback>")
                 .to_owned();
             push_wrapped_error(state, LuaError::CallbackError(traceback, Arc::new(error)));
         } else if !is_wrapped_panic(state, 1) {
@@ -261,7 +267,7 @@ pub unsafe fn resume_with_traceback(
             ffi::luaL_traceback(from, state, ptr::null(), 0);
             let traceback = CStr::from_ptr(ffi::lua_tolstring(from, -1, ptr::null_mut()))
                 .to_str()
-                .unwrap()
+                .unwrap_or_else(|_| "<could not capture traceback>")
                 .to_owned();
             push_wrapped_error(from, LuaError::CallbackError(traceback, Arc::new(error)));
         } else if !is_wrapped_panic(state, 1) {
@@ -321,8 +327,8 @@ pub unsafe fn main_state(state: *mut ffi::lua_State) -> *mut ffi::lua_State {
     state
 }
 
-pub struct WrappedError(LuaError);
-pub struct WrappedPanic(Option<Box<Any + Send>>);
+pub struct WrappedError(pub LuaError);
+pub struct WrappedPanic(pub Option<Box<Any + Send>>);
 
 // Pushes a WrappedError::Error to the top of the stack
 pub unsafe fn push_wrapped_error(state: *mut ffi::lua_State, err: LuaError) {
@@ -427,18 +433,6 @@ pub unsafe fn pop_wrapped_error(state: *mut ffi::lua_State) -> Option<LuaError>
     }
 }
 
-// Pops a WrappedError off of the top of the stack, if it is a WrappedError.  If
-// it is not a WrappedError, returns None and does not pop anything.
-pub unsafe fn pop_wrapped_panic(state: *mut ffi::lua_State) -> Option<Box<Any + Send>> {
-    if ffi::lua_gettop(state) == 0 || !is_wrapped_panic(state, -1) {
-        None
-    } else {
-        let userdata = ffi::lua_touserdata(state, -1);
-        let panic = &mut *(userdata as *mut WrappedPanic);
-        panic.0.take()
-    }
-}
-
 // Checks if the value at the given index is a WrappedError
 pub unsafe fn is_wrapped_error(state: *mut ffi::lua_State, index: c_int) -> bool {
     assert_ne!(