"hoistable" is a misnomer

Author: Rich-Harris

packages/svelte/src/compiler/phases/2-analyze/visitors/Attribute.js

@@ -40,8 +40,8 @@ export function Attribute(node, context) {
 			const delegated_event = get_delegated_event(node.name.slice(2), expression, context);
 
 			if (delegated_event !== null) {
-				if (delegated_event.hoistable) {
-					delegated_event.function.metadata.hoistable = true;
+				if (delegated_event.hoisted) {
+					delegated_event.function.metadata.hoisted = true;
 				}
 
 				node.metadata.delegated = delegated_event;
@@ -70,7 +70,7 @@ function get_delegated_event(event_name, handler, context) {
 	}
 
 	/** @type {DelegatedEvent} */
-	const non_hoistable = { hoistable: false };
+	const non_hoistable = { hoisted: false };
 	/** @type {FunctionExpression | FunctionDeclaration | ArrowFunctionExpression | null} */
 	let target_function = null;
 	let binding = null;
@@ -196,7 +196,7 @@ function get_delegated_event(event_name, handler, context) {
 		visited_references.add(reference);
 	}
 
-	return { hoistable: true, function: target_function };
+	return { hoisted: true, function: target_function };
 }
 
 /**

packages/svelte/src/compiler/phases/2-analyze/visitors/shared/function.js

@@ -8,9 +8,8 @@
 export function visit_function(node, context) {
 	// TODO retire this in favour of a more general solution based on bindings
 	node.metadata = {
-		// module context -> already hoisted
-		hoistable: context.state.ast_type === 'module' ? 'impossible' : false,
-		hoistable_params: [],
+		hoisted: false,
+		hoisted_params: [],
 		scope: context.state.scope
 	};
 

packages/svelte/src/compiler/phases/3-transform/client/utils.js

@@ -481,7 +481,7 @@ export function build_proxy_reassignment(value, proxy_reference) {
  * @param {ComponentContext} context
  * @returns {Pattern[]}
  */
-function get_hoistable_params(node, context) {
+function get_hoisted_params(node, context) {
 	const scope = context.state.scope;
 
 	/** @type {Identifier[]} */
@@ -549,15 +549,15 @@ function get_hoistable_params(node, context) {
  * @param {ComponentContext} context
  * @returns {Pattern[]}
  */
-export function build_hoistable_params(node, context) {
-	const hoistable_params = get_hoistable_params(node, context);
-	node.metadata.hoistable_params = hoistable_params;
+export function build_hoisted_params(node, context) {
+	const hoisted_params = get_hoisted_params(node, context);
+	node.metadata.hoisted_params = hoisted_params;
 
 	/** @type {Pattern[]} */
 	const params = [];
 
 	if (node.params.length === 0) {
-		if (hoistable_params.length > 0) {
+		if (hoisted_params.length > 0) {
 			// For the event object
 			params.push(b.id('_'));
 		}
@@ -567,7 +567,7 @@ export function build_hoistable_params(node, context) {
 		}
 	}
 
-	params.push(...hoistable_params);
+	params.push(...hoisted_params);
 	return params;
 }
 

packages/svelte/src/compiler/phases/3-transform/client/visitors/FunctionDeclaration.js

@@ -1,6 +1,6 @@
 /** @import { FunctionDeclaration } from 'estree' */
 /** @import { ComponentContext } from '../types' */
-import { build_hoistable_params } from '../utils.js';
+import { build_hoisted_params } from '../utils.js';
 import * as b from '../../../../utils/builders.js';
 
 /**
@@ -10,8 +10,8 @@ import * as b from '../../../../utils/builders.js';
 export function FunctionDeclaration(node, context) {
 	const state = { ...context.state, in_constructor: false };
 
-	if (node.metadata?.hoistable === true) {
-		const params = build_hoistable_params(node, context);
+	if (node.metadata?.hoisted === true) {
+		const params = build_hoisted_params(node, context);
 		const body = context.visit(node.body, state);
 
 		context.state.hoisted.push(/** @type {FunctionDeclaration} */ ({ ...node, params, body }));

packages/svelte/src/compiler/phases/3-transform/client/visitors/VariableDeclaration.js

@@ -13,7 +13,7 @@ import {
 	is_state_source,
 	should_proxy_or_freeze
 } from '../utils.js';
-import { is_hoistable_function } from '../../utils.js';
+import { is_hoisted_function } from '../../utils.js';
 
 /**
  * @param {VariableDeclaration} node
@@ -36,11 +36,11 @@ export function VariableDeclaration(node, context) {
 				rune === '$state.snapshot' ||
 				rune === '$state.is'
 			) {
-				if (init != null && is_hoistable_function(init)) {
-					const hoistable_function = context.visit(init);
+				if (init != null && is_hoisted_function(init)) {
 					context.state.hoisted.push(
-						b.declaration('const', declarator.id, /** @type {Expression} */ (hoistable_function))
+						b.declaration('const', declarator.id, /** @type {Expression} */ (context.visit(init)))
 					);
+
 					continue;
 				}
 				declarations.push(/** @type {VariableDeclarator} */ (context.visit(declarator)));
@@ -219,11 +219,9 @@ export function VariableDeclaration(node, context) {
 			if (!has_state && !has_props) {
 				const init = declarator.init;
 
-				if (init != null && is_hoistable_function(init)) {
-					const hoistable_function = context.visit(init);
-
+				if (init != null && is_hoisted_function(init)) {
 					context.state.hoisted.push(
-						b.declaration('const', declarator.id, /** @type {Expression} */ (hoistable_function))
+						b.declaration('const', declarator.id, /** @type {Expression} */ (context.visit(init)))
 					);
 
 					continue;

packages/svelte/src/compiler/phases/3-transform/client/visitors/shared/events.js

@@ -32,19 +32,20 @@ export function visit_event_attribute(node, context) {
 		}
 
 		// Hoist function if we can, otherwise we leave the function as is
-		if (node.metadata.delegated.hoistable) {
+		if (node.metadata.delegated.hoisted) {
 			if (node.metadata.delegated.function === tag.expression) {
 				const func_name = context.state.scope.root.unique('on_' + event_name);
 				context.state.hoisted.push(b.var(func_name, handler));
 				handler = func_name;
 			}
 
-			const hoistable_params = /** @type {Expression[]} */ (
-				node.metadata.delegated.function.metadata.hoistable_params
+			const hoisted_params = /** @type {Expression[]} */ (
+				node.metadata.delegated.function.metadata.hoisted_params
 			);
+
 			// When we hoist a function we assign an array with the function and all
 			// hoisted closure params.
-			const args = [handler, ...hoistable_params];
+			const args = [handler, ...hoisted_params];
 			delegated_assignment = b.array(args);
 		} else {
 			delegated_assignment = handler;

packages/svelte/src/compiler/phases/3-transform/client/visitors/shared/function.js

@@ -1,6 +1,6 @@
 /** @import { ArrowFunctionExpression, FunctionExpression, Node } from 'estree' */
 /** @import { ComponentContext } from '../../types' */
-import { build_hoistable_params } from '../../utils.js';
+import { build_hoisted_params } from '../../utils.js';
 
 /**
  * @param {ArrowFunctionExpression | FunctionExpression} node
@@ -20,8 +20,8 @@ export const visit_function = (node, context) => {
 		state = { ...context.state, in_constructor: false };
 	}
 
-	if (metadata?.hoistable === true) {
-		const params = build_hoistable_params(node, context);
+	if (metadata?.hoisted === true) {
+		const params = build_hoisted_params(node, context);
 
 		return /** @type {FunctionExpression} */ ({
 			...node,

packages/svelte/src/compiler/phases/3-transform/utils.js

@@ -20,13 +20,13 @@ import { dev } from '../../state.js';
  * @param {Node} node
  * @returns {boolean}
  */
-export function is_hoistable_function(node) {
+export function is_hoisted_function(node) {
 	if (
 		node.type === 'ArrowFunctionExpression' ||
 		node.type === 'FunctionExpression' ||
 		node.type === 'FunctionDeclaration'
 	) {
-		return node.metadata?.hoistable === true;
+		return node.metadata?.hoisted === true;
 	}
 	return false;
 }

packages/svelte/src/compiler/phases/types.d.ts

@@ -82,24 +82,24 @@ export interface ComponentAnalysis extends Analysis {
 declare module 'estree' {
 	interface ArrowFunctionExpression {
 		metadata: {
-			hoistable: boolean | 'impossible';
-			hoistable_params: Pattern[];
+			hoisted: boolean;
+			hoisted_params: Pattern[];
 			scope: Scope;
 		};
 	}
 
 	interface FunctionExpression {
 		metadata: {
-			hoistable: boolean | 'impossible';
-			hoistable_params: Pattern[];
+			hoisted: boolean;
+			hoisted_params: Pattern[];
 			scope: Scope;
 		};
 	}
 
 	interface FunctionDeclaration {
 		metadata: {
-			hoistable: boolean | 'impossible';
-			hoistable_params: Pattern[];
+			hoisted: boolean;
+			hoisted_params: Pattern[];
 			scope: Scope;
 		};
 	}

packages/svelte/src/compiler/types/template.d.ts

@@ -214,10 +214,10 @@ export interface OnDirective extends BaseNode {
 
 export type DelegatedEvent =
 	| {
-			hoistable: true;
+			hoisted: true;
 			function: ArrowFunctionExpression | FunctionExpression | FunctionDeclaration;
 	  }
-	| { hoistable: false };
+	| { hoisted: false };
 
 /** A `style:` directive */
 export interface StyleDirective extends BaseNode {