From a6e6b53e1871cc2338cf2ef689e44665922ddc5e Mon Sep 17 00:00:00 2001
From: Serhii Snitsaruk <limbonaut@pm.me>
Date: Tue, 12 Mar 2024 00:30:38 +0100
Subject: [PATCH] Improve prefetching

---
 blackboard/blackboard.cpp      |  3 +--
 blackboard/blackboard.h        |  2 +-
 blackboard/blackboard_plan.cpp | 12 +++++++-----
 3 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/blackboard/blackboard.cpp b/blackboard/blackboard.cpp
index 820b7b1..db43265 100644
--- a/blackboard/blackboard.cpp
+++ b/blackboard/blackboard.cpp
@@ -74,8 +74,7 @@ void Blackboard::unbind_var(const StringName &p_name) {
 	data[p_name].unbind();
 }
 
-void Blackboard::add_var(const StringName &p_name, const BBVariable &p_var) {
-	ERR_FAIL_COND(data.has(p_name));
+void Blackboard::assign_var(const StringName &p_name, const BBVariable &p_var) {
 	data.insert(p_name, p_var);
 }
 
diff --git a/blackboard/blackboard.h b/blackboard/blackboard.h
index 0e8d7cb..2b55396 100644
--- a/blackboard/blackboard.h
+++ b/blackboard/blackboard.h
@@ -54,7 +54,7 @@ public:
 	void bind_var_to_property(const StringName &p_name, Object *p_object, const StringName &p_property);
 	void unbind_var(const StringName &p_name);
 
-	void add_var(const StringName &p_name, const BBVariable &p_var);
+	void assign_var(const StringName &p_name, const BBVariable &p_var);
 
 	// TODO: Add serialization API.
 };
diff --git a/blackboard/blackboard_plan.cpp b/blackboard/blackboard_plan.cpp
index 8d85512..7708088 100644
--- a/blackboard/blackboard_plan.cpp
+++ b/blackboard/blackboard_plan.cpp
@@ -284,14 +284,16 @@ inline void bb_add_var_dup_with_prefetch(const Ref<Blackboard> &p_blackboard, co
 		if (n != nullptr) {
 			var.set_value(n);
 		} else {
-			// Print error only if the variable is not present (it can be initialized by the user or in the parent scope).
-			if (!p_blackboard->has_var(p_name)) {
-				ERR_PRINT(vformat("BlackboardPlan: Prefetch failed for variable $%s with value: %s", p_name, p_var.get_value()));
+			if (p_blackboard->has_var(p_name)) {
+				// Not adding: Assuming variable was initialized by the user or in the parent scope.
+				return;
 			}
+			ERR_PRINT(vformat("BlackboardPlan: Prefetch failed for variable $%s with value: %s", p_name, p_var.get_value()));
+			var.set_value(Variant());
 		}
-		p_blackboard->add_var(p_name, var);
+		p_blackboard->assign_var(p_name, var);
 	} else {
-		p_blackboard->add_var(p_name, p_var.duplicate());
+		p_blackboard->assign_var(p_name, p_var.duplicate());
 	}
 }