From 70f05ac06884c1fe6742f73b103014beae7e4554 Mon Sep 17 00:00:00 2001
From: Jonas Schievink <jonasschievink@gmail.com>
Date: Wed, 2 Aug 2017 14:01:00 +0200
Subject: [PATCH] Remove ErrorError

---
 src/error.rs | 7 -------
 src/util.rs  | 7 ++++++-
 2 files changed, 6 insertions(+), 8 deletions(-)

diff --git a/src/error.rs b/src/error.rs
index 73cfd3f..ec2c95f 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -22,11 +22,6 @@ pub enum Error {
     /// Among other things, this includes invoking operators on wrong types (such as calling or
     /// indexing a `nil` value).
     RuntimeError(String),
-    /// Lua error from inside an error handler, aka `LUA_ERRERR`.
-    ///
-    /// To prevent an infinite recursion when invoking an error handler, this error will be returned
-    /// instead of invoking the error handler.
-    ErrorError(String),
     /// A Rust value could not be converted to a Lua value.
     ToLuaConversionError {
         /// Name of the Rust type that could not be converted.
@@ -108,7 +103,6 @@ impl fmt::Display for Error {
         match *self {
             Error::SyntaxError { ref message, .. } => write!(fmt, "syntax error: {}", message),
             Error::RuntimeError(ref msg) => write!(fmt, "runtime error: {}", msg),
-            Error::ErrorError(ref msg) => write!(fmt, "error in error handler: {}", msg),
             Error::ToLuaConversionError { from, to, ref message } => {
                 write!(fmt, "error converting {} to Lua {}", from, to)?;
                 match *message {
@@ -138,7 +132,6 @@ impl StdError for Error {
         match *self {
             Error::SyntaxError { .. } => "syntax error",
             Error::RuntimeError(_) => "runtime error",
-            Error::ErrorError(_) => "error inside error handler",
             Error::ToLuaConversionError { .. } => "conversion error to lua",
             Error::FromLuaConversionError { .. } => "conversion error from lua",
             Error::CoroutineInactive => "attempt to resume inactive coroutine",
diff --git a/src/util.rs b/src/util.rs
index 345db98..e91b955 100644
--- a/src/util.rs
+++ b/src/util.rs
@@ -287,7 +287,12 @@ pub unsafe fn handle_error(state: *mut ffi::lua_State, err: c_int) -> Result<()>
                         message: err_string,
                     }
                 }
-                ffi::LUA_ERRERR => Error::ErrorError(err_string),
+                ffi::LUA_ERRERR => {
+                    // This can only happen when rlua's own message handler raises an error, which
+                    // should never happen unless there's a bug. This would also be dangerous as it
+                    // longjmps over Rust frames.
+                    lua_panic!(state, "message handler raised error: {}", err_string);
+                }
                 ffi::LUA_ERRMEM => {
                     // This is not impossible to hit, but this library is not set up
                     // to handle this properly.  Lua does a longjmp on out of memory