From 70f4c53854fa759b9d466026e3b23163fc57b371 Mon Sep 17 00:00:00 2001
From: Stephen Chung <schungx@live.com>
Date: Thu, 2 Dec 2021 13:09:59 +0800
Subject: [PATCH] Trap out-of-bounds panic for BLOB's.

---
 CHANGELOG.md  | 1 +
 src/engine.rs | 7 ++++++-
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index d7eeb3e8..020403dd 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -13,6 +13,7 @@ Bug fixes
 ---------
 
 * `from_dynamic` now supports deserializing `Option`.
+* BLOB's no longer panic when accessed with an out-of-bounds index.
 
 Enhancements
 ------------
diff --git a/src/engine.rs b/src/engine.rs
index ac5956bc..aea6638a 100644
--- a/src/engine.rs
+++ b/src/engine.rs
@@ -2052,7 +2052,12 @@ impl Engine {
                     index as usize
                 };
 
-                let value = (arr[arr_idx] as INT).into();
+                let value = arr
+                    .get(arr_idx)
+                    .map(|&v| (v as INT).into())
+                    .ok_or_else(|| {
+                        Box::new(EvalAltResult::ErrorArrayBounds(arr_len, index, idx_pos))
+                    })?;
                 Ok(Target::BlobByte(target, arr_idx, value))
             }