differentiate between 'top-level' and 'needs context preservation' so that SSR errors occur correctly

packages/svelte/src/compiler/phases/2-analyze/index.js

@@ -266,7 +266,7 @@ export function analyze_module(ast, options) {
 		immutable: true,
 		tracing: analysis.tracing,
 		async_deriveds: new Set(),
-		suspenders: new Set()
+		suspenders: new Map()
 	};
 }
 
@@ -455,7 +455,7 @@ export function analyze_component(root, source, options) {
 		snippets: new Set(),
 		is_async: false,
 		async_deriveds: new Set(),
-		suspenders: new Set()
+		suspenders: new Map()
 	};
 
 	if (!runes) {

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

@@ -8,8 +8,11 @@
 export function AwaitExpression(node, context) {
 	const tla = context.state.ast_type === 'instance' && context.state.function_depth === 1;
 	let suspend = tla;
+	let preserve_context = tla;
 
 	if (context.state.expression) {
+		suspend = true;
+
 		// wrap the expression in `(await $.suspend(...)).exit()` if necessary,
 		// i.e. whether anything could potentially be read _after_ the await
 		let i = context.path.length;
@@ -23,7 +26,7 @@ export function AwaitExpression(node, context) {
 
 			// TODO make this more accurate — we don't need to call suspend
 			// if this is the last thing that could be read
-			suspend = true;
+			preserve_context = true;
 		}
 	}
 
@@ -32,7 +35,7 @@ export function AwaitExpression(node, context) {
 			throw new Error('TODO runes mode only');
 		}
 
-		context.state.analysis.suspenders.add(node);
+		context.state.analysis.suspenders.set(node, preserve_context);
 	}
 
 	if (context.state.expression) {

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

@@ -7,7 +7,7 @@ import * as b from '../../../../utils/builders.js';
  * @param {Context} context
  */
 export function AwaitExpression(node, context) {
-	const suspend = context.state.analysis.suspenders.has(node);
+	const suspend = context.state.analysis.suspenders.get(node);
 
 	if (!suspend) {
 		return context.next();

packages/svelte/src/compiler/phases/3-transform/server/visitors/AwaitExpression.js

@@ -7,6 +7,9 @@ import * as b from '../../../../utils/builders.js';
  * @param {ComponentContext} context
  */
 export function AwaitExpression(node, context) {
+	// `has`, not `get`, because all top-level await expressions should
+	// block regardless of whether they need context preservation
+	// in the client output
 	const suspend = context.state.analysis.suspenders.has(node);
 
 	if (!suspend) {

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

@@ -42,8 +42,8 @@ export interface Analysis {
 	/** A set of deriveds that contain `await` expressions */
 	async_deriveds: Set<CallExpression>;
 
-	/** A set of `await` expressions that should trigger suspense */
+	/** A map of `await` expressions that should block, and whether they should preserve context */
-	suspenders: Set<AwaitExpression>;
+	suspenders: Map<AwaitExpression, boolean>;
 }
 
 export interface ComponentAnalysis extends Analysis {