tweak error codes to better align with existing conventions, such as they are

documentation/docs/98-reference/.generated/server-errors.md

@@ -1,6 +1,6 @@
 <!-- This file is generated by scripts/process-messages/index.js. Do not edit! -->
 
-### async_in_sync
+### await_invalid
 
 ```
 Encountered asynchronous work while rendering synchronously.
@@ -8,18 +8,18 @@ Encountered asynchronous work while rendering synchronously.
 
 You (or the framework you're using) used `render` with an async component. Either use `renderAsync` or wrap the async component in a `svelte:boundary` with a `pending` snippet.
 
-### lifecycle_function_unavailable
+### experimental_async_ssr
 
 ```
-`%name%(...)` is not available on the server
+Attempted to use `renderAsync` without `experimental.async` enabled
 ```
 
-Certain methods such as `mount` cannot be invoked while running in a server context. Avoid calling them eagerly, i.e. not during render.
+Set `experimental.async: true` in your compiler options to use async server rendering.
 
-### missing_experimental_flag
+### lifecycle_function_unavailable
 
 ```
-Attempted to use `renderAsync` without `experimental.async` enabled
+`%name%(...)` is not available on the server
 ```
 
-Set `experimental.async: true` in your compiler options to use async server rendering.
+Certain methods such as `mount` cannot be invoked while running in a server context. Avoid calling them eagerly, i.e. not during render.

packages/svelte/messages/server-errors/async.md

@@ -1,10 +1,10 @@
-## async_in_sync
+## await_invalid
 
 > Encountered asynchronous work while rendering synchronously.
 
 You (or the framework you're using) used `render` with an async component. Either use `renderAsync` or wrap the async component in a `svelte:boundary` with a `pending` snippet.
 
-## missing_experimental_flag
+## experimental_async_ssr
 
 > Attempted to use `renderAsync` without `experimental.async` enabled
 

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

@@ -6,8 +6,8 @@ export *  from '../shared/errors.js';
  * Encountered asynchronous work while rendering synchronously.
  * @returns {never}
  */
-export function async_in_sync() {
-	const error = new Error(`async_in_sync\nEncountered asynchronous work while rendering synchronously.\nhttps://svelte.dev/e/async_in_sync`);
+export function await_invalid() {
+	const error = new Error(`await_invalid\nEncountered asynchronous work while rendering synchronously.\nhttps://svelte.dev/e/await_invalid`);
 
 	error.name = 'Svelte error';
 
@@ -18,8 +18,8 @@ export function async_in_sync() {
  * Attempted to use `renderAsync` without `experimental.async` enabled
  * @returns {never}
  */
-export function missing_experimental_flag() {
-	const error = new Error(`missing_experimental_flag\nAttempted to use \`renderAsync\` without \`experimental.async\` enabled\nhttps://svelte.dev/e/missing_experimental_flag`);
+export function experimental_async_ssr() {
+	const error = new Error(`experimental_async_ssr\nAttempted to use \`renderAsync\` without \`experimental.async\` enabled\nhttps://svelte.dev/e/experimental_async_ssr`);
 
 	error.name = 'Svelte error';
 

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

@@ -119,7 +119,7 @@ export function render(component, options = {}) {
  */
 export async function render_async(component, options = {}) {
 	if (!async_mode_flag) {
-		e.missing_experimental_flag();
+		e.experimental_async_ssr();
 	}
 
 	var previous_context = ssr_context;

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

@@ -283,7 +283,7 @@ export class Payload {
 		const result = render(child_payload);
 		if (result instanceof Promise) {
 			if (this.global.mode === 'sync') {
-				e.async_in_sync();
+				e.await_invalid();
 			}
 			// just to avoid unhandled promise rejections -- we'll end up throwing in `collect_async` if something fails
 			result.catch(() => {});

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

@@ -70,7 +70,7 @@ test('creating an async child in a sync context throws', () => {
 			await Promise.resolve();
 			$$payload.push('x');
 		})
-	).toThrow('async_in_sync');
+	).toThrow('await_invalid');
 });
 
 test('collect_async allows awaiting payload to get aggregated content', async () => {

packages/svelte/tests/runtime-runes/samples/async-no-pending-throws-sync/_config.js

@@ -3,5 +3,5 @@ import { test } from '../../test';
 export default test({
 	mode: ['server'],
 
-	error: 'async_in_sync'
+	error: 'await_invalid'
 });