From dc43481fbf967957d60429594607466c968558fb Mon Sep 17 00:00:00 2001
From: Stephen Chung <schungx@live.com>
Date: Thu, 23 May 2024 02:06:37 +0800
Subject: [PATCH] Fix stack overflow bug.

---
 CHANGELOG.md     |  1 +
 src/func/call.rs |  8 ++++++++
 tests/stack.rs   | 17 +++++++++++++++++
 3 files changed, 26 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index ccff89562..4a7d3699a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -13,6 +13,7 @@ Bug fixes
 * The `sync` feature now works properly in `no-std` builds (thanks [`@misssonder`](https://github.com/misssonder) [874](https://github.com/rhaiscript/rhai/pull/874)).
 * More data-race conditions are caught and returned as errors instead of panicking.
 * Missing `min` and `max` functions where both operands are floats or `Decimal` are added.
+* Fixed stack overflow when calling closures recursively (thanks [`@MageWeiG`](https://github.com/MageWeiG) [880](https://github.com/rhaiscript/rhai/issues/880)).
 
 New features
 ------------
diff --git a/src/func/call.rs b/src/func/call.rs
index 3ab5fe92c..3c002b89e 100644
--- a/src/func/call.rs
+++ b/src/func/call.rs
@@ -754,6 +754,8 @@ impl Engine {
                         let scope = &mut Scope::new();
                         let environ = fn_ptr.environ.as_ref().map(<_>::as_ref);
 
+                        defer! { let orig_level = global.level; global.level += 1 }
+
                         self.call_script_fn(
                             global, caches, scope, None, environ, fn_def, args, true, pos,
                         )
@@ -832,6 +834,8 @@ impl Engine {
                         let this_ptr = Some(target.as_mut());
                         let environ = environ.as_deref();
 
+                        defer! { let orig_level = global.level; global.level += 1 }
+
                         self.call_script_fn(
                             global, caches, scope, this_ptr, environ, &fn_def, args, true, pos,
                         )
@@ -973,6 +977,8 @@ impl Engine {
                         let this_ptr = Some(target.as_mut());
                         let args = &mut call_args.iter_mut().collect::<FnArgsVec<_>>();
 
+                        defer! { let orig_level = global.level; global.level += 1 }
+
                         self.call_script_fn(
                             global, caches, scope, this_ptr, environ, &fn_def, args, true, pos,
                         )
@@ -1083,6 +1089,8 @@ impl Engine {
                         let scope = &mut Scope::new();
                         let environ = environ.as_deref();
 
+                        defer! { let orig_level = global.level; global.level += 1 }
+
                         return self.call_script_fn(
                             global, caches, scope, None, environ, &fn_def, args, true, pos,
                         );
diff --git a/tests/stack.rs b/tests/stack.rs
index 1128d2544..f3746abc5 100644
--- a/tests/stack.rs
+++ b/tests/stack.rs
@@ -32,6 +32,23 @@ fn test_stack_overflow_fn_calls() {
             .unwrap_err(),
         EvalAltResult::ErrorStackOverflow(..)
     ));
+
+    #[cfg(not(feature = "no_function"))]
+    #[cfg(not(feature = "no_object"))]
+    assert!(matches!(
+        *engine
+            .run(
+                "
+                    let obj1 = #{
+                        action: || this.action(),	
+                        update: |x| this.action()
+                    };
+                    obj1.update(1)
+                "
+            )
+            .unwrap_err(),
+        EvalAltResult::ErrorStackOverflow(..)
+    ));
 }
 
 #[test]