reduce indirection

packages/svelte/src/internal/server/index.js

@@ -94,7 +94,7 @@ function close(head, body, payload) {
 		cleanup();
 	}
 
-	head += payload.global.head.get_title();
+	head += payload.global.get_title();
 
 	body = BLOCK_OPEN + body + BLOCK_CLOSE; // this inserts a fake boundary so hydration matches
 
@@ -698,7 +698,7 @@ export function build_title(payload, children) {
 	payload.compact({
 		start: i,
 		fn: ({ head }) => {
-			payload.global.head.set_title(head, path);
+			payload.global.set_title(head, path);
 			// since we can only ever render the title in this chunk, and title rendering is handled specially,
 			// we can just ditch the results after we've saved them globally
 			return { head: '', body: '' };

packages/svelte/src/internal/server/payload.js

@@ -368,28 +368,22 @@ export class TreeState {
 	/** @readonly @type {() => string} */
 	uid;
 
-	/** @readonly @type {TreeHeadState} */
-	head;
-
 	/** @readonly @type {Set<{ hash: string; code: string }>} */
 	css = new Set();
 
+	/** @type {{ path: number[], value: string }} */
+	#title = { path: [], value: '' };
+
 	/**
 	 * @param {'sync' | 'async'} mode
 	 * @param {string} [id_prefix]
 	 */
 	constructor(mode, id_prefix = '') {
 		this.mode = mode;
-		this.uid = props_id_generator(id_prefix);
-		this.head = new TreeHeadState();
-	}
-}
 
-export class TreeHeadState {
-	/**
-	 * @type {{ path: number[], value: string }}
-	 */
-	#title = { path: [], value: '' };
+		let uid = 1;
+		this.uid = () => `${id_prefix}s${uid++}`;
+	}
 
 	get_title() {
 		return this.#title.value;
@@ -421,13 +415,3 @@ export class TreeHeadState {
 		}
 	}
 }
-
-/**
- * Creates an ID generator
- * @param {string} prefix
- * @returns {() => string}
- */
-function props_id_generator(prefix) {
-	let uid = 1;
-	return () => `${prefix}s${uid++}`;
-}

packages/svelte/src/internal/server/payload.test.ts

@@ -1,5 +1,5 @@
 import { assert, expect, test } from 'vitest';
-import { Payload, TreeState, TreeHeadState } from './payload.js';
+import { Payload, TreeState } from './payload.js';
 
 test('collects synchronous body content by default', () => {
 	const payload = new Payload(new TreeState('sync'));
@@ -170,7 +170,7 @@ test('subsume replaces tree content and state from other', () => {
 		$$payload.push('body');
 	});
 	b.global.css.add({ hash: 'h', code: 'c' });
-	b.global.head.set_title('Title', [1]);
+	b.global.set_title('Title', [1]);
 	b.local.select_value = 'B';
 	b.promises.initial = Promise.resolve();
 
@@ -192,7 +192,7 @@ test('subsume refuses to switch modes', () => {
 		$$payload.push('body');
 	});
 	b.global.css.add({ hash: 'h', code: 'c' });
-	b.global.head.set_title('Title', [1]);
+	b.global.set_title('Title', [1]);
 	b.local.select_value = 'B';
 	b.promises.initial = Promise.resolve();
 
@@ -206,31 +206,31 @@ test('TreeState uid generator uses prefix', () => {
 	assert.equal(state.uid(), 'id-s1');
 });
 
-test('TreeHeadState title ordering favors later lexicographic paths', () => {
-	const head = new TreeHeadState(() => '');
+test('TreeState title ordering favors later lexicographic paths', () => {
+	const state = new TreeState('sync');
 
-	head.set_title('A', [1]);
-	assert.equal(head.get_title(), 'A');
+	state.set_title('A', [1]);
+	assert.equal(state.get_title(), 'A');
 
 	// equal path -> unchanged
-	head.set_title('B', [1]);
-	assert.equal(head.get_title(), 'A');
+	state.set_title('B', [1]);
+	assert.equal(state.get_title(), 'A');
 
 	// earlier -> unchanged
-	head.set_title('C', [0, 9]);
-	assert.equal(head.get_title(), 'A');
+	state.set_title('C', [0, 9]);
+	assert.equal(state.get_title(), 'A');
 
 	// later -> update
-	head.set_title('D', [2]);
-	assert.equal(head.get_title(), 'D');
+	state.set_title('D', [2]);
+	assert.equal(state.get_title(), 'D');
 
 	// longer but same prefix -> update
-	head.set_title('E', [2, 0]);
-	assert.equal(head.get_title(), 'E');
+	state.set_title('E', [2, 0]);
+	assert.equal(state.get_title(), 'E');
 
 	// shorter (earlier) than current with same prefix -> unchanged
-	head.set_title('F', [2]);
-	assert.equal(head.get_title(), 'E');
+	state.set_title('F', [2]);
+	assert.equal(state.get_title(), 'E');
 });
 
 test('push accepts async functions in async context', async () => {