From 8d34ffb9f571e43bd220b93eb3738a7cc0188319 Mon Sep 17 00:00:00 2001
From: Stephen Chung <schungx@live.com>
Date: Mon, 24 Jan 2022 08:34:21 +0800
Subject: [PATCH] Fix bug in try block.

---
 CHANGELOG.md     |  7 +++++-
 src/eval/stmt.rs | 10 +++++---
 tests/get_set.rs | 65 ++++++++++++++++++++++++++++++++++++++++++++++++
 tests/throw.rs   |  5 ++++
 4 files changed, 83 insertions(+), 4 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 19e31808..80fc04b2 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,9 +1,14 @@
 Rhai Release Notes
 ==================
 
-Version 1.5.0
+Version 1.4.2
 =============
 
+Bug fixes
+---------
+
+* Variables introduced inside `try` blocks are now properly cleaned up upon an exception.
+
 
 Version 1.4.1
 =============
diff --git a/src/eval/stmt.rs b/src/eval/stmt.rs
index 47760a04..96aa85bc 100644
--- a/src/eval/stmt.rs
+++ b/src/eval/stmt.rs
@@ -35,7 +35,7 @@ impl Engine {
             state.scope_level += 1;
         }
 
-        let mut result = Dynamic::UNIT;
+        let mut result = Ok(Dynamic::UNIT);
 
         for stmt in statements {
             let _mods_len = global.num_imports();
@@ -49,7 +49,11 @@ impl Engine {
                 stmt,
                 restore_orig_state,
                 level,
-            )?;
+            );
+
+            if result.is_err() {
+                break;
+            }
 
             #[cfg(not(feature = "no_module"))]
             if matches!(stmt, Stmt::Import(_, _, _)) {
@@ -89,7 +93,7 @@ impl Engine {
             state.always_search_scope = orig_always_search_scope;
         }
 
-        Ok(result)
+        result
     }
 
     /// Evaluate an op-assignment statement.
diff --git a/tests/get_set.rs b/tests/get_set.rs
index ee8e55f5..7ec97451 100644
--- a/tests/get_set.rs
+++ b/tests/get_set.rs
@@ -302,3 +302,68 @@ fn test_get_set_collection() -> Result<(), Box<EvalAltResult>> {
 
     Ok(())
 }
+
+#[cfg(not(feature = "no_index"))]
+#[test]
+fn test_get_set_indexer() -> Result<(), Box<EvalAltResult>> {
+    type MyMap = std::collections::BTreeMap<String, INT>;
+
+    let mut engine = Engine::new();
+
+    engine
+        .register_type_with_name::<MyMap>("MyMap")
+        .register_fn("new_map", || MyMap::new())
+        .register_indexer_get_result(|map: &mut MyMap, index: &str| {
+            map.get(index)
+                .cloned()
+                .ok_or_else(|| format!("Index `{}` not found!", index).into())
+        })
+        .register_indexer_set(|map: &mut MyMap, index: &str, value: INT| {
+            map.insert(index.to_string(), value);
+        })
+        .register_fn("to_string", |map: &mut MyMap| format!("{:?}", map));
+
+    assert_eq!(
+        engine.eval::<INT>(
+            r#"
+                let my_map = new_map();
+                my_map["eggs"] = 42;
+                my_map["eggs"]
+            "#,
+        )?,
+        42
+    );
+
+    assert!(engine
+        .eval::<INT>(
+            r#"
+                let my_map = new_map();
+                my_map["eggs"] = 42;
+                my_map["not_found"]
+            "#,
+        )
+        .is_err());
+
+    assert_eq!(
+        engine.eval::<INT>(
+            r#"
+                let my_map = new_map();
+                my_map["eggs"] = 42;
+            
+                try {
+                    let eggs = my_map["eggs"];
+                    let eggs = my_map["not found"];
+                }
+                catch(x)
+                {
+                    print("Not found!");
+                }
+            
+                my_map["eggs"]
+            "#,
+        )?,
+        42
+    );
+
+    Ok(())
+}
diff --git a/tests/throw.rs b/tests/throw.rs
index e0617559..9aaccab0 100644
--- a/tests/throw.rs
+++ b/tests/throw.rs
@@ -29,6 +29,11 @@ fn test_try_catch() -> Result<(), Box<EvalAltResult>> {
         123
     );
 
+    assert_eq!(
+        engine.eval::<INT>("let x = 42; try { let y = 123; print(x/0); } catch { x = 0 } x")?,
+        0
+    );
+
     #[cfg(not(feature = "no_function"))]
     assert_eq!(
         engine.eval::<INT>(