fix everything but why does it not work

src/runner/instance.rs

@@ -8,7 +8,8 @@ use super::vector3::Vector3;
 
 pub fn set_globals(lua:&mlua::Lua,globals:&mlua::Table)->Result<(),mlua::Error>{
 	//class functions store
-	lua.set_app_data(ClassFunctions::default());
+	lua.set_app_data(ClassMethodsStore::default());
+	lua.set_app_data(InstanceValueStore::default());
 
 	let instance_table=lua.create_table()?;
 
@@ -30,14 +31,10 @@ pub fn set_globals(lua:&mlua::Lua,globals:&mlua::Table)->Result<(),mlua::Error>{
 }
 
 // LMAO look at this function!
-fn dom_mut<T>(lua:&mlua::Lua,mut f:impl FnMut(&mut WeakDom)->mlua::Result<T>)->mlua::Result<T>{
+pub fn dom_mut<T>(lua:&mlua::Lua,mut f:impl FnMut(&mut WeakDom)->mlua::Result<T>)->mlua::Result<T>{
 	let mut dom=lua.app_data_mut::<&'static mut WeakDom>().ok_or(mlua::Error::runtime("DataModel missing"))?;
 	f(&mut *dom)
 }
-fn class_functions_mut<T>(lua:&mlua::Lua,mut f:impl FnMut(&mut ClassFunctions)->mlua::Result<T>)->mlua::Result<T>{
-	let mut cf=lua.app_data_mut::<ClassFunctions>().ok_or(mlua::Error::runtime("ClassFunctions missing"))?;
-	f(&mut *cf)
-}
 
 fn coerce_float32(value:&mlua::Value)->Option<f32>{
 	match value{
@@ -262,7 +259,7 @@ impl mlua::UserData for Instance{
 					other=>return Err(mlua::Error::runtime(format!("Instance.__index Unsupported property type instance={} index={index_str} value={other:?}",instance.name))),
 				}
 				//find a function with a matching name
-				if let Some(function)=class_functions_mut(lua,|cf|{
+				if let Some(function)=class_methods_store_mut(lua,|cf|{
 					let mut iter=SuperClassIter{
 						database:db,
 						descriptor:Some(class),
@@ -275,6 +272,17 @@ impl mlua::UserData for Instance{
 				})?{
 					return function.into_lua(lua);
 				}
+				//find or create an associated userdata object
+
+				if let Some(value)=instance_value_store_mut(lua,|ivs|{
+					//TODO: walk class tree somehow
+					match ivs.get_or_create_instance_values(&instance){
+						Some(mut instance_values)=>instance_values.get_or_create_value(lua,index_str),
+						None=>Ok(None)
+					}
+				})?{
+					return value.into_lua(lua);
+				}
 				//find a child with a matching name
 				find_first_child(dom,instance,index_str)
 				.map(|instance|Instance::new(instance.referent()))
@@ -369,12 +377,13 @@ static CLASS_FUNCTION_DATABASE:CFD=phf::phf_map!{
 		"GetService"=>cf!(|lua,_this,service:mlua::String|{
 			dom_mut(lua,|dom|{
 				//dom.root_ref()==this.referent ?
-				match &*service.to_str()?{
-					"Lighting"=>{
-						let referent=find_first_child_of_class(dom,dom.root(),"Lighting")
+				let service=&*service.to_str()?;
+				match service{
+					"Lighting"|"RunService"=>{
+						let referent=find_first_child_of_class(dom,dom.root(),service)
         				.map(|instance|instance.referent())
 						.unwrap_or_else(||
-							dom.insert(dom.root_ref(),InstanceBuilder::new("Lighting"))
+							dom.insert(dom.root_ref(),InstanceBuilder::new(service))
 						);
 						Ok(Instance::new(referent))
 					},
@@ -391,14 +400,14 @@ static CLASS_FUNCTION_DATABASE:CFD=phf::phf_map!{
 /// A store of created functions for each Roblox class.
 /// Functions are created the first time they are accessed and stored in this data structure.
 #[derive(Default)]
-struct ClassFunctions{
+struct ClassMethodsStore{
 	classes:HashMap<&'static str,//ClassName
 		HashMap<&'static str,//Method name
 			mlua::Function
 		>
 	>
 }
-impl ClassFunctions{
+impl ClassMethodsStore{
 	/// return self.classes[class] or create the ClassMethods and then return it
 	fn get_or_create_class_methods(&mut self,class:&str)->Option<ClassMethods>{
 		// Use get_entry to get the &'static str keys of the database
@@ -433,6 +442,10 @@ impl ClassMethods<'_>{
 		})
 	}
 }
+fn class_methods_store_mut<T>(lua:&mlua::Lua,mut f:impl FnMut(&mut ClassMethodsStore)->mlua::Result<T>)->mlua::Result<T>{
+	let mut cf=lua.app_data_mut::<ClassMethodsStore>().ok_or(mlua::Error::runtime("ClassMethodsStore missing"))?;
+	f(&mut *cf)
+}
 
 /// A virtual property pointer definition shorthand.
 type VirtualPropertyFunctionPointer=fn(&rbx_types::Variant)->Option<rbx_types::Variant>;
@@ -481,3 +494,64 @@ fn find_virtual_property(
 	//Transform Source property with provided function
 	(virtual_property.pointer)(variant)
 }
+
+// lazy-loaded per-instance userdata values
+// This whole thing is a bad idea and a garbage collection nightmare.
+// TODO: recreate rbx_dom_weak with my own instance type that owns this data.
+type CreateUserData=fn(&mlua::Lua)->mlua::Result<mlua::AnyUserData>;
+type LUD=phf::Map<&'static str,// Class name
+	phf::Map<&'static str,// Value name
+		CreateUserData
+	>
+>;
+static LAZY_USER_DATA:LUD=phf::phf_map!{
+	"RunService"=>phf::phf_map!{
+		"RenderStepped"=>|lua|{
+			lua.create_any_userdata(super::script_signal::ScriptSignal::new())
+		},
+	},
+};
+#[derive(Default)]
+pub struct InstanceValueStore{
+	values:HashMap<Ref,
+		HashMap<&'static str,
+			mlua::AnyUserData
+		>
+	>,
+}
+pub struct InstanceValues<'a>{
+	named_values:&'static phf::Map<&'static str,CreateUserData>,
+	values:&'a mut HashMap<&'static str,mlua::AnyUserData>,
+}
+impl InstanceValueStore{
+	pub fn get_or_create_instance_values(&mut self,instance:&rbx_dom_weak::Instance)->Option<InstanceValues>{
+		LAZY_USER_DATA.get(instance.class.as_str())
+			.map(|named_values|
+				InstanceValues{
+					named_values,
+					values:self.values.entry(instance.referent())
+					.or_insert_with(||HashMap::new()),
+				}
+			)
+	}
+}
+impl InstanceValues<'_>{
+	pub fn get_or_create_value(&mut self,lua:&mlua::Lua,index:&str)->mlua::Result<Option<mlua::AnyUserData>>{
+		Ok(match self.named_values.get_entry(index){
+			Some((&static_index_str,&function_pointer))=>Some(
+				match self.values.entry(static_index_str){
+					Entry::Occupied(entry)=>entry.get().clone(),
+					Entry::Vacant(entry)=>entry.insert(
+						function_pointer(lua)?
+					).clone(),
+				}
+			),
+			None=>None,
+		})
+	}
+}
+
+pub fn instance_value_store_mut<T>(lua:&mlua::Lua,mut f:impl FnMut(&mut InstanceValueStore)->mlua::Result<T>)->mlua::Result<T>{
+	let mut cf=lua.app_data_mut::<InstanceValueStore>().ok_or(mlua::Error::runtime("InstanceValueStore missing"))?;
+	f(&mut *cf)
+}

src/runner/mod.rs

@@ -7,7 +7,8 @@ mod color3;
 mod cframe;
 mod vector3;
 pub mod instance;
-mod number_sequence;
+mod script_signal;
 mod color_sequence;
+mod number_sequence;
 
 pub use runner::{Runner,Runnable,Error};

src/runner/runner.rs

@@ -120,4 +120,23 @@ impl Runnable<'_>{
 		}
 		Ok(())
 	}
+	#[cfg(feature="run-service")]
+	pub fn run_service_step(&self)->Result<(),mlua::Error>{
+		let render_stepped=super::instance::dom_mut(&self.lua,|dom|{
+			let run_service=super::instance::find_first_child_of_class(dom,dom.root(),"RunService").ok_or_else(||mlua::Error::runtime("RunService missing"))?;
+			super::instance::instance_value_store_mut(&self.lua,|instance_value_store|{
+				//unwrap because I trust my find_first_child_of_class function to
+				let mut instance_values=instance_value_store.get_or_create_instance_values(run_service).unwrap();
+				let render_stepped=instance_values.get_or_create_value(&self.lua,"RenderStepped")?;
+				//let stepped=instance_values.get_or_create_value(&self.lua,"Stepped")?;
+				//let heartbeat=instance_values.get_or_create_value(&self.lua,"Heartbeat")?;
+				Ok(render_stepped)
+			})
+		})?;
+		if let Some(render_stepped)=render_stepped{
+			let signal:&super::script_signal::ScriptSignal=&*render_stepped.borrow()?;
+			signal.fire(mlua::MultiValue::new());
+		}
+		Ok(())
+	}
 }

src/runner/script_signal.rs

@@ -0,0 +1,79 @@
+use std::{cell::RefCell,rc::Rc};
+
+#[derive(Clone)]
+pub struct ScriptSignal{
+	// Emulate the garbage roblox api.
+	// ScriptConnection should not exist.
+	// :Disconnect should be a method on ScriptSignal, and this would be avoided entirely.
+	callbacks:Rc<RefCell<Vec<mlua::Function>>>,
+}
+pub struct ScriptConnection{
+	signal:ScriptSignal,
+	function:mlua::Function,
+}
+impl ScriptSignal{
+	pub fn new()->Self{
+		Self{
+			callbacks:Rc::new(RefCell::new(Vec::new())),
+		}
+	}
+	// This eats the Lua error
+	pub fn fire(&self,args:mlua::MultiValue){
+		// Make a copy of the list in case Lua attempts to modify it during the loop
+		let functions=self.callbacks.borrow().clone();
+		for function in functions{
+			//wee let's allocate for our function calls
+			if let Err(e)=function.call::<mlua::MultiValue>(args.clone()){
+				println!("Script Signal Error: {e}");
+			}
+		}
+	}
+	pub fn connect(&self,function:mlua::Function)->ScriptConnection{
+		self.callbacks.borrow_mut().push(function.clone());
+		ScriptConnection{
+			signal:self.clone(),
+			function,
+		}
+	}
+}
+impl ScriptConnection{
+	pub fn position(&self)->Option<usize>{
+		self.signal.callbacks.borrow().iter().position(|function|function==&self.function)
+	}
+}
+
+impl mlua::UserData for ScriptSignal{
+	fn add_methods<M:mlua::UserDataMethods<Self>>(methods:&mut M){
+		methods.add_method("Connect",|_lua,this,f:mlua::Function|
+			Ok(this.connect(f))
+		);
+		// Fire is not allowed to be called from Lua
+		// methods.add_method("Fire",|_lua,this,args:mlua::MultiValue|
+		// 	Ok(this.fire(args))
+		// );
+	}
+}
+impl mlua::FromLua for ScriptSignal{
+	fn from_lua(value:mlua::Value,_lua:&mlua::Lua)->Result<Self,mlua::Error>{
+		match value{
+			mlua::Value::UserData(ud)=>Ok(ud.borrow::<Self>()?.clone()),
+			other=>Err(mlua::Error::runtime(format!("Expected {} got {:?}",stringify!(ScriptSignal),other))),
+		}
+	}
+}
+
+impl mlua::UserData for ScriptConnection{
+	fn add_fields<F:mlua::UserDataFields<Self>>(fields:&mut F){
+		fields.add_field_method_get("Connected",|_,this|{
+			Ok(this.position().is_some())
+		});
+	}
+	fn add_methods<M:mlua::UserDataMethods<Self>>(methods:&mut M){
+		methods.add_method("Disconnect",|_,this,_:()|{
+			if let Some(index)=this.position(){
+				this.signal.callbacks.borrow_mut().remove(index);
+			}
+			Ok(())
+		});
+	}
+}

src/scheduler.rs

@@ -61,8 +61,8 @@ pub fn scheduler_mut<T>(lua:&mlua::Lua,mut f:impl FnMut(&mut crate::scheduler::S
 	let mut scheduler=lua.app_data_mut::<crate::scheduler::Scheduler>().ok_or(mlua::Error::runtime("Scheduler missing"))?;
 	f(&mut *scheduler)
 }
-pub fn set_globals(lua:&mlua::Lua,globals:&mlua::Table)->Result<(),mlua::Error>{
-	let schedule_thread=lua.create_function(|lua,dt:mlua::Value|{
+
+fn schedule_thread(lua:&mlua::Lua,dt:mlua::Value)->Result<(),mlua::Error>{
 	let delay=match dt{
 		mlua::Value::Integer(i)=>i.max(0) as u64*60,
 		mlua::Value::Number(f)=>{
@@ -85,21 +85,32 @@ pub fn set_globals(lua:&mlua::Lua,globals:&mlua::Table)->Result<(),mlua::Error>{
 		scheduler.schedule_thread(delay.max(2),lua.current_thread());
 		Ok(())
 	})
-	})?;
-	let wait_env=lua.create_table()?;
-	wait_env.raw_set("coroutine",globals.get::<mlua::Table>("coroutine")?)?;
-	wait_env.raw_set("schedule_thread",schedule_thread)?;
-	let wait=lua.load("
-		local coroutine_yield=coroutine.yield
+}
+
+// This is used to avoid calling coroutine.yield from the rust side.
+const LUA_WAIT:&str=
+"local coroutine_yield=coroutine.yield
 local schedule_thread=schedule_thread
 return function(dt)
 	schedule_thread(dt)
 	return coroutine_yield()
-		end
-	")
+end";
+
+pub fn set_globals(lua:&mlua::Lua,globals:&mlua::Table)->Result<(),mlua::Error>{
+	let coroutine_table=globals.get::<mlua::Table>("coroutine")?;
+	let schedule_thread=lua.create_function(schedule_thread)?;
+
+	//create wait function environment
+	let wait_env=lua.create_table()?;
+	wait_env.raw_set("coroutine",coroutine_table)?;
+	wait_env.raw_set("schedule_thread",schedule_thread)?;
+
+	//construct wait function from Lua code
+	let wait=lua.load(LUA_WAIT)
 	.set_name("wait")
 	.set_environment(wait_env)
 	.call::<mlua::Function>(())?;
+
 	globals.raw_set("wait",wait)?;
 
 	Ok(())