QwikDev · Varixo · Jul 22, 2026
@@ -0,0 +1,5 @@
+---
+'@qwik.dev/optimizer': patch
+---
+
+fix: track props initialized with function call defaults
@@ -8,7 +8,7 @@ use swc_atoms::Atom;
 use swc_common::DUMMY_SP;
 use swc_ecmascript::ast;
 use swc_ecmascript::utils::private_ident;
-use swc_ecmascript::visit::{VisitMut, VisitMutWith};
+use swc_ecmascript::visit::{Visit, VisitMut, VisitMutWith, VisitWith};
 
 struct PropsDestructuring<'a> {
 	component_ident: Option<Id>,
@@ -82,8 +82,8 @@ impl<'a> PropsDestructuring<'a> {
 			}
 
 			let new_ident = private_ident!("_rawProps");
-			if let Some((rest_id_opt, local)) =
-				transform_pat(ast::Expr::Ident(new_ident.clone()), obj, self)
+			if let Some((rest_id_opt, local, default_stmts)) =
+				transform_pat(ast::Expr::Ident(new_ident.clone()), obj, self, true)
 			{
 				if let Some(rest_id) = rest_id_opt {
 					let omit_fn = self.global_collect.import(&_REST_PROPS, self.core_module);
@@ -100,6 +100,7 @@ impl<'a> PropsDestructuring<'a> {
 					self.identifiers.insert(id, expr);
 				}
 				arrow.params[0] = ast::Pat::Ident(ast::BindingIdent::from(new_ident));
+				prepend_stmts(arrow, default_stmts);
 			}
 		}
 		if let ast::BlockStmtOrExpr::BlockStmt(body) = &mut *arrow.body {
@@ -240,8 +241,8 @@ impl<'a> PropsDestructuring<'a> {
 									}
 								}
 								ast::Pat::Object(obj_pat) => {
-									if let Some((rest_id, local)) =
-										transform_pat(new_ref.clone(), obj_pat, self)
+									if let Some((rest_id, local, _)) =
+										transform_pat(new_ref.clone(), obj_pat, self, false)
 									{
 										if let Some(rest_id) = rest_id {
 											let omit_fn = self
@@ -377,15 +378,18 @@ impl<'a> VisitMut for PropsDestructuring<'a> {
 	}
 }
 
-type TransformPatReturn = (Option<Id>, Vec<(Id, Atom, ast::Expr)>);
+type TransformPatReturn = (Option<Id>, Vec<(Id, Atom, ast::Expr)>, Vec<ast::Stmt>);
 fn transform_pat(
 	new_ident: ast::Expr,
 	obj: &ast::ObjectPat,
 	props_transform: &mut PropsDestructuring,
+	allow_dynamic_defaults: bool,
 ) -> Option<TransformPatReturn> {
 	let mut local = vec![];
+	let mut default_stmts = vec![];
 	let mut skip = false;
 	let mut rest_id = None;
+	let destructured_names = collect_destructured_names(obj);
 	for prop in &obj.props {
 		match prop {
 			ast::ObjectPatProp::Assign(ref v) => {
@@ -406,6 +410,13 @@ fn transform_pat(
 								right: value.clone(),
 							}),
 						));
+					} else if allow_dynamic_defaults
+						&& !references_destructured_name(value, &destructured_names)
+					{
+						let (default_expr, default_stmt) =
+							create_dynamic_default(access, value.clone());
+						local.push((id!(v.key), v.key.sym.clone(), default_expr));
+						default_stmts.push(default_stmt);
 					} else {
 						skip = true;
 					}
@@ -469,6 +480,18 @@ fn transform_pat(
 										right: value.clone(),
 									}),
 								));
+							} else if allow_dynamic_defaults
+								&& !references_destructured_name(value, &destructured_names)
+							{
+								let access = ast::Expr::Member(ast::MemberExpr {
+									obj: Box::new(new_ident.clone()),
+									prop,
+									span: DUMMY_SP,
+								});
+								let (default_expr, default_stmt) =
+									create_dynamic_default(access, value.clone());
+								local.push((id!(ident.id), key_atom.clone(), default_expr));
+								default_stmts.push(default_stmt);
 							} else {
 								skip = true;
 							}
@@ -494,7 +517,65 @@ fn transform_pat(
 		return None;
 	}
 	// Allow case with only rest binding (no local fields)
-	Some((rest_id, local))
+	Some((rest_id, local, default_stmts))
+}
+
+fn create_dynamic_default(access: ast::Expr, value: Box<ast::Expr>) -> (ast::Expr, ast::Stmt) {
+	let default_ident = private_ident!("_defaultValue");
+	let default_stmt = ast::Stmt::Decl(ast::Decl::Var(Box::new(ast::VarDecl {
+		kind: ast::VarDeclKind::Const,
+		decls: vec![ast::VarDeclarator {
+			definite: false,
+			span: DUMMY_SP,
+			init: Some(Box::new(ast::Expr::Cond(ast::CondExpr {
+				span: DUMMY_SP,
+				test: Box::new(is_undefined(access.clone())),
+				cons: value,
+				alt: ast::Expr::undefined(DUMMY_SP),
+			}))),
+			name: ast::Pat::Ident(ast::BindingIdent::from(default_ident.clone())),
+		}],
+		..Default::default()
+	})));
+	let default_expr = ast::Expr::Cond(ast::CondExpr {
+		span: DUMMY_SP,
+		test: Box::new(is_undefined(access.clone())),
+		cons: Box::new(ast::Expr::Ident(default_ident)),
+		alt: Box::new(access),
+	});
+
+	(default_expr, default_stmt)
+}
+
+fn is_undefined(expr: ast::Expr) -> ast::Expr {
+	ast::Expr::Bin(ast::BinExpr {
+		span: DUMMY_SP,
+		op: ast::BinaryOp::EqEqEq,
+		left: Box::new(expr),
+		right: ast::Expr::undefined(DUMMY_SP),
+	})
+}
+
+fn references_destructured_name(expr: &ast::Expr, names: &HashSet<Id>) -> bool {
+	struct Finder<'a> {
+		names: &'a HashSet<Id>,
+		found: bool,
+	}
+
+	impl Visit for Finder<'_> {
+		fn visit_ident(&mut self, ident: &ast::Ident) {
+			if self.names.contains(&id!(ident)) {
+				self.found = true;
+			}
+		}
+	}
+
+	let mut finder = Finder {
+		names,
+		found: false,
+	};
+	expr.visit_with(&mut finder);
+	finder.found
 }
 
 fn transform_rest(
@@ -528,13 +609,21 @@ fn transform_rest(
 	} else {
 		create_omit_props(omit_fn, rest_id, props_expr, omit)
 	};
+	prepend_stmts(arrow, vec![new_stmt]);
+}
+
+fn prepend_stmts(arrow: &mut ast::ArrowExpr, mut stmts: Vec<ast::Stmt>) {
+	if stmts.is_empty() {
+		return;
+	}
 	match &mut arrow.body {
 		box ast::BlockStmtOrExpr::BlockStmt(block) => {
-			block.stmts.insert(0, new_stmt);
+			block.stmts.splice(0..0, stmts);
 		}
 		box ast::BlockStmtOrExpr::Expr(ref expr) => {
+			stmts.push(create_return_stmt(expr.clone()));
 			arrow.body = Box::new(ast::BlockStmtOrExpr::BlockStmt(ast::BlockStmt {
-				stmts: vec![new_stmt, create_return_stmt(expr.clone())],
+				stmts,
 				..Default::default()
 			}));
 		}

@@ -8,6 +8,7 @@ expression: output
 
 import { $, component$, useTask$ } from '@qwik.dev/core';
 import { CONST } from 'const';
+const getValue = () => 0;
 export const Works = component$(({
 	count,
 	some = 1+2,
@@ -36,17 +37,22 @@ export const NoWorks2 = component$(({count, stuff: {hey}}) => {
 	);
 });
 
-export const NoWorks3 = component$(({count, stuff = hola()}) => {
+export const DynamicDefaults = component$(({count, stuff = getValue(), other: value = getValue()}) => {
 	console.log(stuff);
 	useTask$(({track}) => {
-		track(() => count);
-		console.log(count);
+		track(() => stuff);
+		track(() => value);
+		console.log(count, stuff, value);
 	});
 	return (
-		<div class={count}>{count}</div>
+		<div class={stuff}>{value}</div>
 	);
 });
 
+export const ReferencedDefault = component$(({first = getValue(second), second}) => (
+	<div>{first}{second}</div>
+));
+
 ============================= test.js ==
 
 import { _restProps } from "@qwik.dev/core";
@@ -67,11 +73,16 @@ const _hf1 = (p0)=>({
         some: p0.some ?? 3
     });
 const _hf1_str = "{some:p0.some??1+2}";
+const _hf2 = (p0, p1)=>p1.stuff === void 0 ? p0 : p1.stuff;
+const _hf2_str = "p1.stuff===void 0?p0:p1.stuff";
+const _hf3 = (p0, p1)=>p1.other === void 0 ? p0 : p1.other;
+const _hf3_str = "p1.other===void 0?p0:p1.other";
 //
+const q_DynamicDefaults_component_nZOHO1uiqf4 = /*#__PURE__*/ _noopQrl("DynamicDefaults_component_nZOHO1uiqf4");
+const q_DynamicDefaults_component_useTask_Od2wjq7X07c = /*#__PURE__*/ _noopQrl("DynamicDefaults_component_useTask_Od2wjq7X07c");
 const q_NoWorks2_component_JPD9t2HyEKg = /*#__PURE__*/ _noopQrl("NoWorks2_component_JPD9t2HyEKg");
 const q_NoWorks2_component_useTask_lXiqwbxxjq0 = /*#__PURE__*/ _noopQrl("NoWorks2_component_useTask_lXiqwbxxjq0");
-const q_NoWorks3_component_fc13h5yYn14 = /*#__PURE__*/ _noopQrl("NoWorks3_component_fc13h5yYn14");
-const q_NoWorks3_component_useTask_3cQGU0s1VwU = /*#__PURE__*/ _noopQrl("NoWorks3_component_useTask_3cQGU0s1VwU");
+const q_ReferencedDefault_component_xTfXU3xq5Ow = /*#__PURE__*/ _noopQrl("ReferencedDefault_component_xTfXU3xq5Ow");
 const q_Works_component_t45qL4vNGv0 = /*#__PURE__*/ _noopQrl("Works_component_t45qL4vNGv0");
 const q_Works_component_useTask_pjo5U5Ikll0 = /*#__PURE__*/ _noopQrl("Works_component_useTask_pjo5U5Ikll0");
 //
@@ -121,26 +132,44 @@ q_NoWorks2_component_JPD9t2HyEKg.s(({ count, stuff: { hey } })=>{
         class: count
     }, null, count, 1, "u6_1");
 });
-q_NoWorks3_component_useTask_3cQGU0s1VwU.s(({ track })=>{
-    const count = _captures[0];
-    track(()=>count);
-    console.log(count);
+q_DynamicDefaults_component_useTask_Od2wjq7X07c.s(({ track })=>{
+    const _defaultValue = _captures[0], _defaultValue1 = _captures[1], _rawProps = _captures[2];
+    track(()=>_rawProps.stuff === void 0 ? _defaultValue : _rawProps.stuff);
+    track(()=>_rawProps.other === void 0 ? _defaultValue1 : _rawProps.other);
+    console.log(_rawProps.count, _rawProps.stuff === void 0 ? _defaultValue : _rawProps.stuff, _rawProps.other === void 0 ? _defaultValue1 : _rawProps.other);
 });
-q_NoWorks3_component_fc13h5yYn14.s(({ count, stuff = hola() })=>{
-    console.log(stuff);
-    useTaskQrl(q_NoWorks3_component_useTask_3cQGU0s1VwU.w([
-        count
+const getValue = ()=>0;
+q_DynamicDefaults_component_nZOHO1uiqf4.s((_rawProps)=>{
+    const _defaultValue = _rawProps.stuff === void 0 ? getValue() : void 0;
+    const _defaultValue1 = _rawProps.other === void 0 ? getValue() : void 0;
+    console.log(_rawProps.stuff === void 0 ? _defaultValue : _rawProps.stuff);
+    useTaskQrl(q_DynamicDefaults_component_useTask_Od2wjq7X07c.w([
+        _defaultValue,
+        _defaultValue1,
+        _rawProps
     ]));
     return /*#__PURE__*/ _jsxSorted("div", {
-        class: count
-    }, null, count, 1, "u6_2");
+        class: _fnSignal(_hf2, [
+            _defaultValue,
+            _rawProps
+        ], _hf2_str)
+    }, null, _fnSignal(_hf3, [
+        _defaultValue1,
+        _rawProps
+    ], _hf3_str), 1, "u6_2");
 });
+q_ReferencedDefault_component_xTfXU3xq5Ow.s(({ first = getValue(second), second })=>/*#__PURE__*/ _jsxSorted("div", null, null, [
+        first,
+        second
+    ], 1, "u6_3"));
 export const Works = /*#__PURE__*/ componentQrl(q_Works_component_t45qL4vNGv0);
 export const NoWorks2 = /*#__PURE__*/ componentQrl(q_NoWorks2_component_JPD9t2HyEKg);
-export const NoWorks3 = /*#__PURE__*/ componentQrl(q_NoWorks3_component_fc13h5yYn14);
+export const DynamicDefaults = /*#__PURE__*/ componentQrl(q_DynamicDefaults_component_nZOHO1uiqf4);
+export const ReferencedDefault = /*#__PURE__*/ componentQrl(q_ReferencedDefault_component_xTfXU3xq5Ow);
+export { getValue as _auto_getValue };
 
 
-Some("{\"version\":3,\"sources\":[\"/user/qwik/src/test.tsx\"],\"names\":[],\"mappings\":\";;;;;;;;;;;;sBAKC,QAAO;;mBAWmB,CAAA;QAAE,IAAI,KAXhC,QAAO;IAW0B,CAAA;;;;;;;;;;wCALxB,CAAC,EAAC,KAAK,EAAC;;IAChB,MAAM,cARP;IASC,QAAQ,GAAG,WATZ,OASoB,gBANpB,iBAFA,QAAO,aAGP,gBAAqB;;gCALU;;;;;;;;IAO/B,QAAQ,GAAG,WAHX,iBAFA,QAAO;IAMP;;;;IAIA,qBACC,UAAC;QAAI,IAAI;;;QAAQ,MAAM;;;QAAY,KAAK;wBAAa;;0BAAA;QAAM,QAAQ;;AAErE;2CAIU,CAAC,EAAC,KAAK,EAAC;;IAChB,MAAM,IAAM;IACZ,QAAQ,GAAG,CAAC;;mCAJqB,CAAC,EAAC,KAAK,EAAE,OAAO,EAAC,GAAG,EAAC,EAAC;IACxD,QAAQ,GAAG,CAAC;IACZ;;;IAIA,qBACC,WAAC;QAAI,OAAO;aAAQ;AAEtB;2CAIU,CAAC,EAAC,KAAK,EAAC;;IAChB,MAAM,IAAM;IACZ,QAAQ,GAAG,CAAC;;mCAJqB,CAAC,EAAC,KAAK,EAAE,QAAQ,MAAM,EAAC;IAC1D,QAAQ,GAAG,CAAC;IACZ;;;IAIA,qBACC,WAAC;QAAI,OAAO;aAAQ;AAEtB;AArCA,OAAO,MAAM,sBAAQ,4CAelB;AAEH,OAAO,MAAM,yBAAW,+CASrB;AAEH,OAAO,MAAM,yBAAW,+CASrB\"}")
+Some("{\"version\":3,\"sources\":[\"/user/qwik/src/test.tsx\"],\"names\":[],\"mappings\":\";;;;;;;;;;;;sBAMC,QAAO;;mBAWmB,CAAA;QAAE,IAAI,KAXhC,QAAO;IAW0B,CAAA;;0BAeiB,2BAAA;;0BAAoB,2BAAA;;;;;;;;;;;wCApB7D,CAAC,EAAC,KAAK,EAAC;;IAChB,MAAM,cARP;IASC,QAAQ,GAAG,WATZ,OASoB,gBANpB,iBAFA,QAAO,aAGP,gBAAqB;;gCALU;;;;;;;;IAO/B,QAAQ,GAAG,WAHX,iBAFA,QAAO;IAMP;;;;IAIA,qBACC,UAAC;QAAI,IAAI;;;QAAQ,MAAM;;;QAAY,KAAK;wBAAa;;0BAAA;QAAM,QAAQ;;AAErE;2CAIU,CAAC,EAAC,KAAK,EAAC;;IAChB,MAAM,IAAM;IACZ,QAAQ,GAAG,CAAC;;mCAJqB,CAAC,EAAC,KAAK,EAAE,OAAO,EAAC,GAAG,EAAC,EAAC;IACxD,QAAQ,GAAG,CAAC;IACZ;;;IAIA,qBACC,WAAC;QAAI,OAAO;aAAQ;AAEtB;kDAIU,CAAC,EAAC,KAAK,EAAC;;IAChB,MAAM,cAH2C,6CAAA;IAIjD,MAAM,cAJ+D,8CAAA;IAKrE,QAAQ,GAAG,WAL+B,iBAAO,6CAAA,iBAAoB,8CAAA;;AA7BvE,MAAM,WAAW,IAAM;0CA6BmB;oCAAS,mBAAQ;qCAAY,mBAAe;IACrF,QAAQ,GAAG,WADuC,6CAAA;IAElD;;;;;IAKA,qBACC,WAAC;QAAI,KAAK;;;;;;;;AAEZ;4CAE4C,CAAC,EAAC,QAAQ,SAAS,OAAO,EAAE,MAAM,EAAC,iBAC9E,WAAC;QAAK;QAAO;;AAzCd,OAAO,MAAM,sBAAQ,4CAelB;AAEH,OAAO,MAAM,yBAAW,+CASrB;AAEH,OAAO,MAAM,gCAAkB,sDAU5B;AAEH,OAAO,MAAM,kCAAoB,wDAE9B\"}")
 == DIAGNOSTICS ==
 
 []
@@ -517,6 +517,7 @@ fn example_props_optimization() {
 		code: r#"
 import { $, component$, useTask$ } from '@qwik.dev/core';
 import { CONST } from 'const';
+const getValue = () => 0;
 export const Works = component$(({
 	count,
 	some = 1+2,
@@ -545,16 +546,21 @@ export const NoWorks2 = component$(({count, stuff: {hey}}) => {
 	);
 });
 
-export const NoWorks3 = component$(({count, stuff = hola()}) => {
+export const DynamicDefaults = component$(({count, stuff = getValue(), other: value = getValue()}) => {
 	console.log(stuff);
 	useTask$(({track}) => {
-		track(() => count);
-		console.log(count);
+		track(() => stuff);
+		track(() => value);
+		console.log(count, stuff, value);
 	});
 	return (
-		<div class={count}>{count}</div>
+		<div class={stuff}>{value}</div>
 	);
 });
+
+export const ReferencedDefault = component$(({first = getValue(second), second}) => (
+	<div>{first}{second}</div>
+));
 "#
 		.to_string(),
 		transpile_jsx: true,