From 71711998f19702d6f3532852e9ae97ac66751bd1 Mon Sep 17 00:00:00 2001
From: Stephen Chung <schungx@live.com>
Date: Fri, 3 Sep 2021 10:05:58 +0800
Subject: [PATCH] Fix bug in catch error variable.

---
 CHANGELOG.md   |  2 +-
 src/parse.rs   | 12 ++++++++++--
 tests/throw.rs | 12 ++++++++++++
 3 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7084cebb..121f589e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,7 +1,7 @@
 Rhai Release Notes
 ==================
 
-Version 1.0.3
+Version 1.0.4
 =============
 
 Bug fixes
diff --git a/src/parse.rs b/src/parse.rs
index e383d597..3750599f 100644
--- a/src/parse.rs
+++ b/src/parse.rs
@@ -2902,7 +2902,7 @@ fn parse_try_catch(
     }
 
     // try { body } catch (
-    let var_def = if match_token(input, Token::LeftParen).0 {
+    let err_var = if match_token(input, Token::LeftParen).0 {
         let (name, pos) = parse_var_name(input)?;
         let (matched, err_pos) = match_token(input, Token::RightParen);
 
@@ -2924,8 +2924,16 @@ fn parse_try_catch(
     // try { body } catch ( var ) { catch_block }
     let catch_body = parse_block(input, state, lib, settings.level_up())?;
 
+    if err_var.is_some() {
+        // Remove the error variable from the stack
+        state
+            .stack
+            .pop()
+            .expect("stack contains at least one entry");
+    }
+
     Ok(Stmt::TryCatch(
-        (body.into(), var_def, catch_body.into()).into(),
+        (body.into(), err_var, catch_body.into()).into(),
         settings.pos,
     ))
 }
diff --git a/tests/throw.rs b/tests/throw.rs
index a93cfd04..2ef82dd2 100644
--- a/tests/throw.rs
+++ b/tests/throw.rs
@@ -51,6 +51,18 @@ fn test_try_catch() -> Result<(), Box<EvalAltResult>> {
         42
     );
 
+    assert_eq!(
+        engine.eval::<INT>(
+            "
+                let err = 123;
+                let x = 0;
+                try { throw 42; } catch(err) { print(err); }
+                err
+            "
+        )?,
+        123
+    );
+
     assert_eq!(
         engine.eval::<INT>(
             "