5 files changed, 67 insertions, 0 deletions

diff --git a/core/extension/gdextension.cpp b/core/extension/gdextension.cpp
index 9a735f5aa6..1e4cd81034 100644
--- a/core/extension/gdextension.cpp
+++ b/core/extension/gdextension.cpp
@@ -485,6 +485,13 @@ void GDExtension::close_library() {
 	ERR_FAIL_COND(library == nullptr);
 	OS::get_singleton()->close_dynamic_library(library);
 
+#if defined(TOOLS_ENABLED) && defined(WINDOWS_ENABLED)
+	// Delete temporary copy of library if it exists.
+	if (!temp_lib_path.is_empty() && Engine::get_singleton()->is_editor_hint()) {
+		DirAccess::remove_absolute(temp_lib_path);
+	}
+#endif
+
 	library = nullptr;
 }
 
@@ -641,6 +648,40 @@ Ref<Resource> GDExtensionResourceLoader::load(const String &p_path, const String
 	Ref<GDExtension> lib;
 	lib.instantiate();
 	String abs_path = ProjectSettings::get_singleton()->globalize_path(library_path);
+
+#if defined(WINDOWS_ENABLED) && defined(TOOLS_ENABLED)
+	// If running on the editor on Windows, we copy the library and open the copy.
+	// This is so the original file isn't locked and can be updated by a compiler.
+	if (Engine::get_singleton()->is_editor_hint()) {
+		if (!FileAccess::exists(abs_path)) {
+			if (r_error) {
+				*r_error = ERR_FILE_NOT_FOUND;
+			}
+			ERR_PRINT("GDExtension library not found: " + library_path);
+			return Ref<Resource>();
+		}
+
+		// Copy the file to the same directory as the original with a prefix in the name.
+		// This is so relative path to dependencies are satisfied.
+		String copy_path = abs_path.get_base_dir().path_join("~" + abs_path.get_file());
+
+		Error copy_err = DirAccess::copy_absolute(abs_path, copy_path);
+		if (copy_err) {
+			if (r_error) {
+				*r_error = ERR_CANT_CREATE;
+			}
+			ERR_PRINT("Error copying GDExtension library: " + library_path);
+			return Ref<Resource>();
+		}
+		FileAccess::set_hidden_attribute(copy_path, true);
+
+		// Save the copied path so it can be deleted later.
+		lib->set_temp_library_path(copy_path);
+
+		// Use the copy to open the library.
+		abs_path = copy_path;
+	}
+#endif
 	err = lib->open_library(abs_path, entry_symbol);
 
 	if (r_error) {
diff --git a/core/extension/gdextension.h b/core/extension/gdextension.h
index b935f8706f..5a4dd3d5f5 100644
--- a/core/extension/gdextension.h
+++ b/core/extension/gdextension.h
@@ -43,6 +43,9 @@ class GDExtension : public Resource {
 
 	void *library = nullptr; // pointer if valid,
 	String library_path;
+#if defined(WINDOWS_ENABLED) && defined(TOOLS_ENABLED)
+	String temp_lib_path;
+#endif
 
 	struct Extension {
 		ObjectGDExtension gdextension;
@@ -76,6 +79,10 @@ public:
 	Error open_library(const String &p_path, const String &p_entry_symbol);
 	void close_library();
 
+#if defined(WINDOWS_ENABLED) && defined(TOOLS_ENABLED)
+	void set_temp_library_path(const String &p_path) { temp_lib_path = p_path; }
+#endif
+
 	enum InitializationLevel {
 		INITIALIZATION_LEVEL_CORE = GDEXTENSION_INITIALIZATION_CORE,
 		INITIALIZATION_LEVEL_SERVERS = GDEXTENSION_INITIALIZATION_SERVERS,
diff --git a/core/string/ustring.cpp b/core/string/ustring.cpp
index 376d0832d4..80ca51573c 100644
--- a/core/string/ustring.cpp
+++ b/core/string/ustring.cpp
@@ -3635,6 +3635,23 @@ String String::repeat(int p_count) const {
 	return new_string;
 }
 
+String String::reverse() const {
+	int len = length();
+	if (len <= 1) {
+		return *this;
+	}
+	String new_string;
+	new_string.resize(len + 1);
+
+	const char32_t *src = ptr();
+	char32_t *dst = new_string.ptrw();
+	for (int i = 0; i < len; i++) {
+		dst[i] = src[len - i - 1];
+	}
+	dst[len] = _null;
+	return new_string;
+}
+
 String String::left(int p_len) const {
 	if (p_len < 0) {
 		p_len = length() + p_len;
diff --git a/core/string/ustring.h b/core/string/ustring.h
index 295625395d..f45392eee1 100644
--- a/core/string/ustring.h
+++ b/core/string/ustring.h
@@ -305,6 +305,7 @@ public:
 	String replace(const char *p_key, const char *p_with) const;
 	String replacen(const String &p_key, const String &p_with) const;
 	String repeat(int p_count) const;
+	String reverse() const;
 	String insert(int p_at_pos, const String &p_string) const;
 	String erase(int p_pos, int p_chars = 1) const;
 	String pad_decimals(int p_digits) const;
diff --git a/core/variant/variant_call.cpp b/core/variant/variant_call.cpp
index dad9183216..ccf9b82022 100644
--- a/core/variant/variant_call.cpp
+++ b/core/variant/variant_call.cpp
@@ -1659,6 +1659,7 @@ static void _register_variant_builtin_methods() {
 	bind_string_methodv(replace, static_cast<String (String::*)(const String &, const String &) const>(&String::replace), sarray("what", "forwhat"), varray());
 	bind_string_method(replacen, sarray("what", "forwhat"), varray());
 	bind_string_method(repeat, sarray("count"), varray());
+	bind_string_method(reverse, sarray(), varray());
 	bind_string_method(insert, sarray("position", "what"), varray());
 	bind_string_method(erase, sarray("position", "chars"), varray(1));
 	bind_string_method(capitalize, sarray(), varray());