perf: use native `Map.prototype.getOrInsert(Computed)` in `Warp` when available

documentation/docs/07-misc/.generated/browser-support-features.md

@@ -1,7 +1,3 @@
 <!-- generated in ../../../../../packages/svelte/scripts/generate-browser-support.ts. do not edit -->
 
-| Feature | Chrome/Edge | Firefox | Safari |
+_No features currently require browser versions newer than the runtime floor._
-| - | - | - | - |
-| [`$state.snapshot`](/docs/svelte/$state#$state.snapshot) | 98 | 94 | 15.4 |
-| [`bind:devicePixelContentBoxSize`](/docs/svelte/bind#Dimensions) | <span style="color: var(--sk-fg-4)">—</span> | 93 | not supported |
-| [`flip` from `svelte/animate`](/docs/svelte/svelte-animate#flip) | <span style="color: var(--sk-fg-4)">—</span> | 126 | <span style="color: var(--sk-fg-4)">—</span> |

documentation/docs/07-misc/.generated/browser-support.md

@@ -2,14 +2,12 @@
 
 | Browser | Minimum version |
 | - | - |
-| Chrome/Edge | 87 |
+| Chrome/Edge | 148 |
-| Firefox | 83 |
+| Firefox | 151 |
-| Safari | 14 |
+| Safari | 26.5 |
-| Opera | 73 |
+| Opera | 132 |
-| Opera (Android) | 62 |
+| Android WebView | 148 |
-| Samsung Internet | 14.0 |
-| Android WebView | 87 |
 | Internet Explorer | not supported |
 
 
-> [!NOTE] This equates to a <a href="https://web-platform-dx.github.io/baseline/">Baseline</a> target of 2020.
+> [!NOTE] This equates to a <a href="https://web-platform-dx.github.io/baseline/">Baseline</a> target of 2026.

packages/svelte/src/internal/client/warp.js

@@ -1,6 +1,7 @@
 /** @import { WarpKey } from '#shared' */
 import { async_mode_flag } from '../flags/index.js';
 import * as e from './errors.js';
+import { get_or_insert, get_or_insert_computed } from '../shared/utils.js';
 
 /**
  * A `Map` whose contents are sent from the server to the client. Values added to it
@@ -76,10 +77,7 @@ export class Warp {
 	 * @returns {V}
 	 */
 	getOrInsert(key, value) {
-		const values = this.#values();
+		return get_or_insert(this.#values(), key, value);
-		if (values.has(key)) return /** @type {V} */ (values.get(key));
-		values.set(key, value);
-		return value;
 	}
 
 	/**
@@ -89,11 +87,7 @@ export class Warp {
 	 * @returns {V}
 	 */
 	getOrInsertComputed(key, callback) {
-		const values = this.#values();
+		return get_or_insert_computed(this.#values(), key, callback);
-		if (values.has(key)) return /** @type {V} */ (values.get(key));
-		const value = callback(key);
-		values.set(key, value);
-		return value;
 	}
 
 	/**

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

@@ -5,6 +5,7 @@ import { async_mode_flag } from '../flags/index.js';
 import { get_render_context } from './render-context.js';
 import { get_user_code_location } from './dev.js';
 import * as e from './errors.js';
+import { get_or_insert_computed } from '../shared/utils.js';
 
 /**
  * A `Map` whose contents are sent from the server to the client. Values added to it
@@ -71,10 +72,10 @@ export class Warp {
 		const store = get_store();
 		const values = /** @type {Map<K, V>} */ (get_values(store, this.#id));
 
-		if (values.has(key)) return /** @type {V} */ (values.get(key));
+		return get_or_insert_computed(values, key, () => {
-
+			record(store, this.#id, key, value);
-		set(store, this.#id, key, value);
+			return value;
-		return value;
+		});
 	}
 
 	/**
@@ -87,11 +88,11 @@ export class Warp {
 		const store = get_store();
 		const values = /** @type {Map<K, V>} */ (get_values(store, this.#id));
 
-		if (values.has(key)) return /** @type {V} */ (values.get(key));
+		return get_or_insert_computed(values, key, (key) => {
-
+			const value = callback(key);
-		const value = callback(key);
+			record(store, this.#id, key, value);
-		set(store, this.#id, key, value);
+			return value;
-		return value;
+		});
 	}
 
 	/**
@@ -174,12 +175,23 @@ function get_values(store, id) {
  * @param {unknown} value
  */
 function set(store, id, key, value) {
+	record(store, id, key, value);
+	get_values(store, id).set(key, value);
+}
+
+/**
+ * Does everything that needs to happen when a value is added, other than actually adding it.
+ * Throws if it can't be added, so that `getOrInsertComputed` doesn't add it either
+ * @param {WarpStore} store
+ * @param {string} id
+ * @param {WarpKey} key
+ * @param {unknown} value
+ */
+function record(store, id, key, value) {
 	if (store.emitted) {
 		e.warp_set_after_render(id, String(key));
 	}
 
-	get_values(store, id).set(key, value);
-
 	if (DEV) {
 		let stacks = store.stacks.get(id);
 

packages/svelte/src/internal/shared/utils.js

@@ -13,6 +13,9 @@ export var array_prototype = Array.prototype;
 export var get_prototype_of = Object.getPrototypeOf;
 export var is_extensible = Object.isExtensible;
 export var has_own_property = Object.prototype.hasOwnProperty;
+// these are new, and not available everywhere yet
+var map_get_or_insert = /** @type {any} */ (Map.prototype).getOrInsert;
+var map_get_or_insert_computed = /** @type {any} */ (Map.prototype).getOrInsertComputed;
 
 /**
  * @param {any} thing
@@ -24,6 +27,40 @@ export function is_function(thing) {
 
 export const noop = () => {};
 
+/**
+ * `map.getOrInsert(key, value)`, using the native implementation if there is one
+ * @template K, V
+ * @param {Map<K, V>} map
+ * @param {K} key
+ * @param {V} value
+ * @returns {V}
+ */
+export function get_or_insert(map, key, value) {
+	if (map_get_or_insert !== undefined) return map_get_or_insert.call(map, key, value);
+	if (map.has(key)) return /** @type {V} */ (map.get(key));
+	map.set(key, value);
+	return value;
+}
+
+/**
+ * `map.getOrInsertComputed(key, callback)`, using the native implementation if there is one
+ * @template K, V
+ * @param {Map<K, V>} map
+ * @param {K} key
+ * @param {(key: K) => V} callback
+ * @returns {V}
+ */
+export function get_or_insert_computed(map, key, callback) {
+	if (map_get_or_insert_computed !== undefined) {
+		return map_get_or_insert_computed.call(map, key, callback);
+	}
+
+	if (map.has(key)) return /** @type {V} */ (map.get(key));
+	const value = callback(key);
+	map.set(key, value);
+	return value;
+}
+
 // Adapted from https://github.com/then/is-promise/blob/master/index.js
 // Distributed under MIT License https://github.com/then/is-promise/blob/master/LICENSE