From c407dc09de51174c1ac18ff839f91228f3938cc2 Mon Sep 17 00:00:00 2001
From: Rich Harris <rich.harris@vercel.com>
Date: Thu, 15 May 2025 18:14:27 -0400
Subject: [PATCH] make analysis available at transform time

---
 .../svelte/src/compiler/phases/2-analyze/index.js  |  7 +++----
 .../src/compiler/phases/2-analyze/types.d.ts       |  1 -
 .../phases/2-analyze/visitors/ClassBody.js         |  2 ++
 packages/svelte/src/compiler/phases/types.d.ts     | 14 ++++++++++++--
 4 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/packages/svelte/src/compiler/phases/2-analyze/index.js b/packages/svelte/src/compiler/phases/2-analyze/index.js
index c29ddd9146..51180ca7cc 100644
--- a/packages/svelte/src/compiler/phases/2-analyze/index.js
+++ b/packages/svelte/src/compiler/phases/2-analyze/index.js
@@ -256,7 +256,8 @@ export function analyze_module(ast, options) {
 		accessors: false,
 		runes: true,
 		immutable: true,
-		tracing: false
+		tracing: false,
+		classes: new Map()
 	};
 
 	walk(
@@ -265,7 +266,6 @@ export function analyze_module(ast, options) {
 			scope,
 			scopes,
 			analysis: /** @type {ComponentAnalysis} */ (analysis),
-			classes: new Map(),
 			state_fields: null,
 			// TODO the following are not needed for modules, but we have to pass them in order to avoid type error,
 			// and reducing the type would result in a lot of tedious type casts elsewhere - find a good solution one day
@@ -430,6 +430,7 @@ export function analyze_component(root, source, options) {
 		elements: [],
 		runes,
 		tracing: false,
+		classes: new Map(),
 		immutable: runes || options.immutable,
 		exports: [],
 		uses_props: false,
@@ -625,7 +626,6 @@ export function analyze_component(root, source, options) {
 				has_props_rune: false,
 				component_slots: new Set(),
 				expression: null,
-				classes: new Map(),
 				state_fields: null,
 				function_depth: scope.function_depth,
 				reactive_statement: null
@@ -693,7 +693,6 @@ export function analyze_component(root, source, options) {
 				reactive_statement: null,
 				component_slots: new Set(),
 				expression: null,
-				classes: new Map(),
 				state_fields: null,
 				function_depth: scope.function_depth
 			};
diff --git a/packages/svelte/src/compiler/phases/2-analyze/types.d.ts b/packages/svelte/src/compiler/phases/2-analyze/types.d.ts
index 3bbab7d067..328dc4deb1 100644
--- a/packages/svelte/src/compiler/phases/2-analyze/types.d.ts
+++ b/packages/svelte/src/compiler/phases/2-analyze/types.d.ts
@@ -21,7 +21,6 @@ export interface AnalysisState {
 	expression: ExpressionMetadata | null;
 
 	/** Used to analyze class state. */
-	classes: Map<ClassBody, Record<string, StateField>>;
 	state_fields: Record<string, StateField> | null;
 
 	function_depth: number;
diff --git a/packages/svelte/src/compiler/phases/2-analyze/visitors/ClassBody.js b/packages/svelte/src/compiler/phases/2-analyze/visitors/ClassBody.js
index 829a9293b7..46e1fc1a17 100644
--- a/packages/svelte/src/compiler/phases/2-analyze/visitors/ClassBody.js
+++ b/packages/svelte/src/compiler/phases/2-analyze/visitors/ClassBody.js
@@ -18,6 +18,8 @@ export function ClassBody(node, context) {
 	/** @type {Record<string, StateField>} */
 	const state_fields = {};
 
+	context.state.analysis.classes.set(node, state_fields);
+
 	/** @type {string[]} */
 	const seen = [];
 
diff --git a/packages/svelte/src/compiler/phases/types.d.ts b/packages/svelte/src/compiler/phases/types.d.ts
index 22e749c97b..6e3aa9e026 100644
--- a/packages/svelte/src/compiler/phases/types.d.ts
+++ b/packages/svelte/src/compiler/phases/types.d.ts
@@ -1,7 +1,15 @@
-import type { AST, Binding } from '#compiler';
-import type { AssignmentExpression, Identifier, LabeledStatement, Node, Program } from 'estree';
+import type { AST, Binding, StateField } from '#compiler';
+import type {
+	AssignmentExpression,
+	ClassBody,
+	Identifier,
+	LabeledStatement,
+	Node,
+	Program
+} from 'estree';
 import type { Scope, ScopeRoot } from './scope.js';
 import type { StateCreationRuneName } from '../../utils.js';
+import type { AnalysisState } from './2-analyze/types.js';
 
 export interface Js {
 	ast: Program;
@@ -30,6 +38,8 @@ export interface Analysis {
 	immutable: boolean;
 	tracing: boolean;
 
+	classes: Map<ClassBody, Record<string, StateField>>;
+
 	// TODO figure out if we can move this to ComponentAnalysis
 	accessors: boolean;
 }