fix

packages/svelte/scripts/process-messages/templates/compile-warnings.js

@@ -1,4 +1,4 @@
-import { warnings, ignore_stack, ignore_map, filter_warning } from './state.js';
+import { warnings, ignore_stack, ignore_map, warning_filter } from './state.js';
 import { CompileDiagnostic } from './utils/compile_diagnostic.js';
 
 /** @typedef {{ start?: number, end?: number }} NodeLike */
@@ -34,7 +34,7 @@ function w(node, code, message) {
 		node && node.start !== undefined ? [node.start, node.end ?? node.start] : undefined
 	);
 
-	if (!filter_warning(warning)) return;
+	if (!warning_filter(warning)) return;
 
 	warnings.push(warning);
 }

packages/svelte/src/compiler/index.js

@@ -20,6 +20,7 @@ export { default as preprocess } from './preprocess/index.js';
  * @returns {CompileResult}
  */
 export function compile(source, options) {
+	state.reset_warning_filter(options.warningFilter);
 	const validated = validate_component_options(options, '');
 	state.reset(source, validated);
 
@@ -58,6 +59,7 @@ export function compile(source, options) {
  * @returns {CompileResult}
  */
 export function compileModule(source, options) {
+	state.reset_warning_filter(options.warningFilter);
 	const validated = validate_module_options(options, '');
 	state.reset(source, validated);
 
@@ -103,6 +105,7 @@ export function compileModule(source, options) {
  * @returns {Root | LegacyRoot}
  */
 export function parse(source, { filename, rootDir, modern } = {}) {
+	state.reset_warning_filter(() => false);
 	state.reset(source, { filename, rootDir }); // TODO it's weird to require filename/rootDir here. reconsider the API
 
 	const ast = _parse(source);

packages/svelte/src/compiler/migrate/index.js

@@ -10,7 +10,7 @@ import { parse } from '../phases/1-parse/index.js';
 import { analyze_component } from '../phases/2-analyze/index.js';
 import { validate_component_options } from '../validate-options.js';
 import { get_rune } from '../phases/scope.js';
-import { reset } from '../state.js';
+import { reset, reset_warning_filter } from '../state.js';
 import { extract_identifiers } from '../utils/ast.js';
 import { regex_is_valid_identifier } from '../phases/patterns.js';
 import { migrate_svelte_ignore } from '../utils/extract_svelte_ignore.js';
@@ -24,6 +24,7 @@ import { migrate_svelte_ignore } from '../utils/extract_svelte_ignore.js';
  */
 export function migrate(source) {
 	try {
+		reset_warning_filter(() => false);
 		reset(source, { filename: 'migrate.svelte' });
 
 		let parsed = parse(source);

packages/svelte/src/compiler/state.js

@@ -51,9 +51,17 @@ export function pop_ignore() {
 	ignore_stack.pop();
 }
 
+/**
+ *
+ * @param {(warning: Warning) => boolean} fn
+ */
+export function reset_warning_filter(fn = () => true) {
+	warning_filter = fn;
+}
+
 /**
  * @param {string} _source
- * @param {{ filename?: string, rootDir?: string, warningFilter?: CompileOptions['warningFilter'] }} options
+ * @param {{ filename?: string, rootDir?: string }} options
  */
 export function reset(_source, options) {
 	source = _source;
@@ -70,7 +78,6 @@ export function reset(_source, options) {
 	}
 
 	locator = getLocator(source, { offsetLine: 1 });
-	warning_filter = options.warningFilter ?? (() => true);
 	warnings = [];
 	ignore_stack = [];
 	ignore_map.clear();

packages/svelte/src/compiler/warnings.js

@@ -744,4 +744,4 @@ export function slot_element_deprecated(node) {
  */
 export function svelte_element_invalid_this(node) {
 	w(node, "svelte_element_invalid_this", "`this` should be an `{expression}`. Using a string attribute value will cause an error in future versions of Svelte");
-}
+}