From 63674648fb97c297a0e516c2bbb108274721a21a Mon Sep 17 00:00:00 2001
From: Paul Joannon <hello@pauljoannon.com>
Date: Thu, 7 Mar 2024 20:19:05 +0100
Subject: [PATCH] Fix how scripts reload outside of ScriptEditor

---
 core/io/resource.cpp            |  1 +
 core/object/script_language.cpp | 19 +++++++++++++++++++
 core/object/script_language.h   |  2 ++
 3 files changed, 22 insertions(+)

diff --git a/core/io/resource.cpp b/core/io/resource.cpp
index 7e8d0b43cd2..e2b43096e18 100644
--- a/core/io/resource.cpp
+++ b/core/io/resource.cpp
@@ -204,6 +204,7 @@ Error Resource::copy_from(const Ref<Resource> &p_resource) {
 	}
 	return OK;
 }
+
 void Resource::reload_from_file() {
 	String path = get_path();
 	if (!path.is_resource_file()) {
diff --git a/core/object/script_language.cpp b/core/object/script_language.cpp
index 693c6819d47..0b6c9c7057c 100644
--- a/core/object/script_language.cpp
+++ b/core/object/script_language.cpp
@@ -34,6 +34,7 @@
 #include "core/core_string_names.h"
 #include "core/debugger/engine_debugger.h"
 #include "core/debugger/script_debugger.h"
+#include "core/io/resource_loader.h"
 
 #include <stdint.h>
 
@@ -154,6 +155,24 @@ void Script::_bind_methods() {
 	ADD_PROPERTY(PropertyInfo(Variant::STRING, "source_code", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_NONE), "set_source_code", "get_source_code");
 }
 
+void Script::reload_from_file() {
+#ifdef TOOLS_ENABLED
+	// Replicates how the ScriptEditor reloads script resources, which generally handles it.
+	// However, when scripts are to be reloaded but aren't open in the internal editor, we go through here instead.
+	const Ref<Script> rel = ResourceLoader::load(ResourceLoader::path_remap(get_path()), get_class(), ResourceFormatLoader::CACHE_MODE_IGNORE);
+	if (rel.is_null()) {
+		return;
+	}
+
+	set_source_code(rel->get_source_code());
+	set_last_modified_time(rel->get_last_modified_time());
+
+	reload();
+#else
+	Resource::reload_from_file();
+#endif
+}
+
 void ScriptServer::set_scripting_enabled(bool p_enabled) {
 	scripting_enabled = p_enabled;
 }
diff --git a/core/object/script_language.h b/core/object/script_language.h
index 95e9d2b4aff..2ddc6a2590b 100644
--- a/core/object/script_language.h
+++ b/core/object/script_language.h
@@ -125,6 +125,8 @@ protected:
 	Dictionary _get_script_constant_map();
 
 public:
+	virtual void reload_from_file() override;
+
 	virtual bool can_instantiate() const = 0;
 
 	virtual Ref<Script> get_base_script() const = 0; //for script inheritance