Fix issue with self in functional components

packages/imba/changelog.md

@@ -2,6 +2,11 @@
 
 ## Unreleased
 
+* Fix issue with self in functional components.
+
+    Event handlers inside functional components could refer to to the wrong
+    `self` if called multiple times with different `self` values.
+
 * Major performance fix for certain css selectors.
 
     When using selectors like `^@hover prop:value` Imba would compile

packages/imba/src/compiler/nodes.imba1

@@ -4448,8 +4448,11 @@ export class IsolatedFunc < Func
 		if let leaks = @scope.@leaks
 			@leaks = []
 			leaks.forEach do |shadow,source|
-				shadow.@proxy = @params.at(@params.count,yes)
-				@leaks.push(source)
+				if shadow.@name == 'self'
+					@useSelf = shadow
+				else
+					shadow.@proxy = @params.at(@params.count,yes)
+					@leaks.push(source)
 		self
 
 export class IifeFunc < Func
@@ -9373,6 +9376,13 @@ export class TagModifier < TagPart
 
 		if @name isa IsolatedFunc
 			@value = @name
+
+			let root = STACK.parents(TagLike)[0]
+			if root
+				root.set(memoSelf: yes)
+				# should only be needed _if_ self is referenced? But this is a micro optimization
+				let op = @value.@scope.@context = OP('.',root.parentCache,STR('this'))
+
 			@name = STR('$_')
 			@params = ListNode.new([@value].concat(@value.leaks or []))
 
@@ -9590,6 +9600,7 @@ export class TagHandlerCallback < ValueNode
 			val = val.value
 
 		if val isa Func
+			# TODO Warn / error if func has arguments
 			val = val.body
 
 		# If the value is just a variable we can add it directly?
@@ -10772,6 +10783,10 @@ export class Tag < TagLike
 
 		# console.log "IS INLINE? {o:inline} {STACK.isExpression} {!!@consumedBy} {!!@parent} {isDetached}"
 
+		# if option(:memoSelf)
+		if !parent and option(:memoSelf) # scope__.@context # and scope__.@context.@reference
+			add "{parentCache}.this=this"
+
 		if !@consumedBy
 			@ref = "{tvar}"
 

packages/imba/src/imba/events/core.imba

@@ -201,6 +201,7 @@ export def use_events
 	yes
 
 # could cache similar event handlers with the same parts
+# Should be possible to remove closure from EventHandler
 export class EventHandler
 	def constructor params,closure
 		self.params = params

packages/imba/test/apps/rendering/functional-self.imba

@@ -0,0 +1,26 @@
+
+class Item
+	count = 0
+	def node val
+		<div @click=(count++)>
+
+tag App
+	# the default value of label will be inherited
+	# from the closest parent that has a label property
+	prop label = #context.label
+	item = new Item
+	options = {}
+
+	def render
+		<self>	
+			<(item.node(options))>
+
+test do
+	let app = new <App>
+	ok app.item.count == 0
+	app.children[0].click()
+	ok app.item.count == 1
+	app.item = new Item
+	app.render!
+	app.children[0].click()
+	ok app.item.count == 1