From 810fcc74318a4fcb12997d20d3738cd5e349430c Mon Sep 17 00:00:00 2001
From: baptr <1522777+baptr@users.noreply.github.com>
Date: Sun, 26 Feb 2023 19:42:55 -0800
Subject: [PATCH] Fix gdscript analyzer error when instantiating EditorPlugins.

Editor code is not instantiable outside of the editor
(https://github.com/godotengine/godot/blob/1d14c054a12dacdc193b589e4afb0ef319ee2aae/core/object/class_db.cpp#L369).
This is fine for editor plugins and the like, but the GDScript analyzer
balks at it, causing F5 runs to fail: #73525.

Instead, we really just want to know if the type is abstract - so add
a new ClassDB method to check that and nothing else.

Update core/object/class_db.cpp

Apply code review comments

Co-Authored-By: Bryce <1522777+baptr@users.noreply.github.com>
---
 core/object/class_db.cpp               | 15 +++++++++++++++
 core/object/class_db.h                 |  1 +
 modules/gdscript/gdscript_analyzer.cpp |  2 +-
 3 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/core/object/class_db.cpp b/core/object/class_db.cpp
index fe4345aa0d9..cca83b514d6 100644
--- a/core/object/class_db.cpp
+++ b/core/object/class_db.cpp
@@ -671,6 +671,21 @@ bool ClassDB::can_instantiate(const StringName &p_class) {
 	return (!ti->disabled && ti->creation_func != nullptr && !(ti->gdextension && !ti->gdextension->create_instance));
 }
 
+bool ClassDB::is_abstract(const StringName &p_class) {
+	OBJTYPE_RLOCK;
+
+	ClassInfo *ti = classes.getptr(p_class);
+	if (!ti) {
+		if (!ScriptServer::is_global_class(p_class)) {
+			ERR_FAIL_V_MSG(false, "Cannot get class '" + String(p_class) + "'.");
+		}
+		String path = ScriptServer::get_global_class_path(p_class);
+		Ref<Script> scr = ResourceLoader::load(path);
+		return scr.is_valid() && scr->is_valid() && scr->is_abstract();
+	}
+	return ti->creation_func == nullptr && (!ti->gdextension || ti->gdextension->create_instance == nullptr);
+}
+
 bool ClassDB::is_virtual(const StringName &p_class) {
 	OBJTYPE_RLOCK;
 
diff --git a/core/object/class_db.h b/core/object/class_db.h
index 37a864c1090..caee2e8e107 100644
--- a/core/object/class_db.h
+++ b/core/object/class_db.h
@@ -287,6 +287,7 @@ public:
 	static bool class_exists(const StringName &p_class);
 	static bool is_parent_class(const StringName &p_class, const StringName &p_inherits);
 	static bool can_instantiate(const StringName &p_class);
+	static bool is_abstract(const StringName &p_class);
 	static bool is_virtual(const StringName &p_class);
 	static Object *instantiate(const StringName &p_class);
 	static Object *instantiate_no_placeholders(const StringName &p_class);
diff --git a/modules/gdscript/gdscript_analyzer.cpp b/modules/gdscript/gdscript_analyzer.cpp
index a6b4bce000d..67b40a6198f 100644
--- a/modules/gdscript/gdscript_analyzer.cpp
+++ b/modules/gdscript/gdscript_analyzer.cpp
@@ -5180,7 +5180,7 @@ bool GDScriptAnalyzer::get_function_signature(GDScriptParser::Node *p_source, bo
 		if (!class_exists(base_native)) {
 			push_error(vformat("Native class %s used in script doesn't exist or isn't exposed.", base_native), p_source);
 			return false;
-		} else if (p_is_constructor && !ClassDB::can_instantiate(base_native)) {
+		} else if (p_is_constructor && ClassDB::is_abstract(base_native)) {
 			if (p_base_type.kind == GDScriptParser::DataType::CLASS) {
 				push_error(vformat(R"(Class "%s" cannot be constructed as it is based on abstract native class "%s".)", p_base_type.class_type->fqcn.get_file(), base_native), p_source);
 			} else if (p_base_type.kind == GDScriptParser::DataType::SCRIPT) {