From f4949a2beb805cc5531836de3a6768eea4e00c4f Mon Sep 17 00:00:00 2001
From: Stephen Chung <schungx@live.com>
Date: Fri, 27 Jan 2023 22:31:14 +0800
Subject: [PATCH] Always search scope after scope is modified.

---
 src/eval/debugger.rs | 11 +++++++++--
 src/eval/expr.rs     | 11 ++++++++++-
 src/eval/stmt.rs     |  9 ++++++++-
 3 files changed, 27 insertions(+), 4 deletions(-)

diff --git a/src/eval/debugger.rs b/src/eval/debugger.rs
index 1bc1a5a5..652134a3 100644
--- a/src/eval/debugger.rs
+++ b/src/eval/debugger.rs
@@ -505,14 +505,21 @@ impl Engine {
         event: DebuggerEvent,
     ) -> Result<Option<DebuggerStatus>, Box<crate::EvalAltResult>> {
         if let Some(ref x) = self.debugger_interface {
+            let orig_scope_len = scope.len();
+
             let src = global.source_raw().cloned();
             let src = src.as_ref().map(|s| s.as_str());
             let context = EvalContext::new(self, global, caches, scope, this_ptr);
             let (.., ref on_debugger) = **x;
 
-            let command = on_debugger(context, event, node, src, node.position())?;
+            let command = on_debugger(context, event, node, src, node.position());
 
-            match command {
+            if orig_scope_len != scope.len() {
+                // The scope is changed, always search from now on
+                global.always_search_scope = true;
+            }
+
+            match command? {
                 DebuggerCommand::Continue => {
                     global.debugger_mut().status = DebuggerStatus::CONTINUE;
                     Ok(None)
diff --git a/src/eval/expr.rs b/src/eval/expr.rs
index 75d9c0a5..925a8132 100644
--- a/src/eval/expr.rs
+++ b/src/eval/expr.rs
@@ -174,9 +174,18 @@ impl Engine {
 
         // Check the variable resolver, if any
         if let Some(ref resolve_var) = self.resolve_var {
+            let orig_scope_len = scope.len();
+
             let context = EvalContext::new(self, global, caches, scope, this_ptr);
             let var_name = expr.get_variable_name(true).expect("`Expr::Variable`");
-            match resolve_var(var_name, index, context) {
+            let resolved_var = resolve_var(var_name, index, context);
+
+            if orig_scope_len != scope.len() {
+                // The scope is changed, always search from now on
+                global.always_search_scope = true;
+            }
+
+            match resolved_var {
                 Ok(Some(mut result)) => {
                     result.set_access_mode(AccessMode::ReadOnly);
                     return Ok(result.into());
diff --git a/src/eval/stmt.rs b/src/eval/stmt.rs
index db2523ff..f9111ce6 100644
--- a/src/eval/stmt.rs
+++ b/src/eval/stmt.rs
@@ -728,10 +728,17 @@ impl Engine {
                         nesting_level: global.scope_level,
                         will_shadow,
                     };
+                    let orig_scope_len = scope.len();
                     let context =
                         EvalContext::new(self, global, caches, scope, this_ptr.as_deref_mut());
+                    let filter_result = filter(true, info, context);
 
-                    if !filter(true, info, context)? {
+                    if orig_scope_len != scope.len() {
+                        // The scope is changed, always search from now on
+                        global.always_search_scope = true;
+                    }
+
+                    if !filter_result? {
                         return Err(ERR::ErrorForbiddenVariable(var_name.to_string(), *pos).into());
                     }
                 }