chore: refactor logic for ignoring warnings (#11300)

* reimplement svelte-ignore logic

* simplify

* remove unused code

* remove ignores array from comment node

* unused

* regenerate types

* types

* oops, again

Author: Rich-Harris

packages/svelte/src/compiler/legacy.js

@@ -4,6 +4,7 @@ import {
 	regex_not_whitespace,
 	regex_starts_with_whitespaces
 } from './phases/patterns.js';
+import { extract_svelte_ignore } from './utils/extract_svelte_ignore.js';
 
 /**
  * Some of the legacy Svelte AST nodes remove whitespace from the start and end of their children.
@@ -197,7 +198,13 @@ export function convert(source, ast) {
 			ClassDirective(node) {
 				return { ...node, type: 'Class' };
 			},
-			ComplexSelector(node, { visit }) {
+			Comment(node) {
+				return {
+					...node,
+					ignores: extract_svelte_ignore(node.data)
+				};
+			},
+			ComplexSelector(node) {
 				const children = [];
 
 				for (const child of node.children) {

packages/svelte/src/compiler/phases/1-parse/state/element.js

@@ -1,5 +1,3 @@
-import { extract_svelte_ignore } from '../../../utils/extract_svelte_ignore.js';
-import fuzzymatch from '../utils/fuzzymatch.js';
 import { is_void } from '../utils/names.js';
 import read_expression from '../read/expression.js';
 import { read_script } from '../read/script.js';
@@ -87,8 +85,7 @@ export default function tag(parser) {
 			type: 'Comment',
 			start,
 			end: parser.index,
-			data,
-			ignores: extract_svelte_ignore(data)
+			data
 		});
 
 		return;

packages/svelte/src/compiler/phases/2-analyze/a11y.js

@@ -667,9 +667,8 @@ function get_static_text_value(attribute) {
 /**
  * @param {import('#compiler').RegularElement | import('#compiler').SvelteElement} node
  * @param {import('./types.js').AnalysisState} state
- * @param {import('#compiler').SvelteNode[]} path
  */
-function check_element(node, state, path) {
+function check_element(node, state) {
 	// foreign namespace means elements can have completely different meanings, therefore we don't check them
 	if (state.options.namespace === 'foreign') return;
 
@@ -680,8 +679,7 @@ function check_element(node, state, path) {
 	 * @param  {Parameters<import('../../warnings.js').AllWarnings[T]>} args
 	 * @returns {void}
 	 */
-	const push_warning = (node, code, ...args) =>
-		warn(state.analysis.warnings, node, path, code, ...args);
+	const push_warning = (node, code, ...args) => warn(state.analysis.warnings, node, code, ...args);
 
 	/** @type {Map<string, import('#compiler').Attribute>} */
 	const attribute_map = new Map();
@@ -1165,9 +1163,9 @@ function check_element(node, state, path) {
  */
 export const a11y_validators = {
 	RegularElement(node, context) {
-		check_element(node, context.state, context.path);
+		check_element(node, context.state);
 	},
 	SvelteElement(node, context) {
-		check_element(node, context.state, context.path);
+		check_element(node, context.state);
 	}
 };

packages/svelte/src/compiler/phases/2-analyze/css/css-warn.js

@@ -26,7 +26,7 @@ const visitors = {
 		if (!node.metadata.used) {
 			const content = context.state.stylesheet.content;
 			const text = content.styles.substring(node.start - content.start, node.end - content.start);
-			warn(context.state.warnings, node, context.path, 'css-unused-selector', text);
+			warn(context.state.warnings, node, 'css-unused-selector', text);
 		}
 
 		context.next();

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

@@ -24,6 +24,7 @@ import { analyze_css } from './css/css-analyze.js';
 import { prune } from './css/css-prune.js';
 import { hash } from './utils.js';
 import { warn_unused } from './css/css-warn.js';
+import { extract_svelte_ignore } from '../../utils/extract_svelte_ignore.js';
 
 /**
  * @param {import('#compiler').Script | null} script
@@ -330,7 +331,7 @@ export function analyze_component(root, source, options) {
 				} else if (declaration !== null && Runes.includes(/** @type {any} */ (name))) {
 					for (const { node, path } of references) {
 						if (path.at(-1)?.type === 'CallExpression') {
-							warn(warnings, node, [], 'store-with-rune-name', store_name);
+							warn(warnings, node, 'store-with-rune-name', store_name);
 						}
 					}
 				}
@@ -407,7 +408,7 @@ export function analyze_component(root, source, options) {
 	};
 
 	if (!options.customElement && root.options?.customElement) {
-		warn(analysis.warnings, root.options, [], 'missing-custom-element-compile-option');
+		warn(analysis.warnings, root.options, 'missing-custom-element-compile-option');
 	}
 
 	if (analysis.runes) {
@@ -433,7 +434,8 @@ export function analyze_component(root, source, options) {
 				component_slots: new Set(),
 				expression: null,
 				private_derived_state: [],
-				function_depth: scope.function_depth
+				function_depth: scope.function_depth,
+				ignores: new Set()
 			};
 
 			walk(
@@ -475,7 +477,8 @@ export function analyze_component(root, source, options) {
 				component_slots: new Set(),
 				expression: null,
 				private_derived_state: [],
-				function_depth: scope.function_depth
+				function_depth: scope.function_depth,
+				ignores: new Set()
 			};
 
 			walk(
@@ -495,7 +498,7 @@ export function analyze_component(root, source, options) {
 					(r) => r.node !== binding.node && r.path.at(-1)?.type !== 'ExportSpecifier'
 				);
 				if (!references.length && !instance.scope.declarations.has(`$${name}`)) {
-					warn(warnings, binding.node, [], 'unused-export-let', name);
+					warn(warnings, binding.node, 'unused-export-let', name);
 				}
 			}
 		}
@@ -535,15 +538,15 @@ export function analyze_component(root, source, options) {
 									type === 'AwaitBlock' ||
 									type === 'KeyBlock'
 								) {
-									warn(warnings, binding.node, [], 'non-state-reference', name);
+									warn(warnings, binding.node, 'non-state-reference', name);
 									continue outer;
 								}
 							}
 							continue inner;
 						}
 					}
 
-					warn(warnings, binding.node, [], 'non-state-reference', name);
+					warn(warnings, binding.node, 'non-state-reference', name);
 					continue outer;
 				}
 			}
@@ -557,7 +560,13 @@ export function analyze_component(root, source, options) {
 		for (const element of analysis.elements) {
 			prune(analysis.css.ast, element);
 		}
-		warn_unused(analysis.css.ast, analysis.warnings);
+
+		if (
+			!analysis.css.ast.content.comment ||
+			!extract_svelte_ignore(analysis.css.ast.content.comment.data).includes('css-unused-selector')
+		) {
+			warn_unused(analysis.css.ast, analysis.warnings);
+		}
 
 		outer: for (const element of analysis.elements) {
 			if (element.metadata.scoped) {
@@ -679,7 +688,7 @@ const legacy_scope_tweaker = {
 				(d) => d.scope === state.analysis.module.scope && d.declaration_kind !== 'const'
 			)
 		) {
-			warn(state.analysis.warnings, node, path, 'module-script-reactive-declaration');
+			warn(state.analysis.warnings, node, 'module-script-reactive-declaration');
 		}
 
 		if (
@@ -1045,6 +1054,65 @@ const function_visitor = (node, context) => {
 
 /** @type {import('./types').Visitors} */
 const common_visitors = {
+	_(node, context) {
+		// @ts-expect-error
+		const comments = /** @type {import('estree').Comment[]} */ (node.leadingComments);
+
+		if (comments) {
+			/** @type {string[]} */
+			const ignores = [];
+
+			for (const comment of comments) {
+				ignores.push(...extract_svelte_ignore(comment.value));
+			}
+
+			if (ignores.length > 0) {
+				// @ts-expect-error see below
+				node.ignores = new Set([...context.state.ignores, ...ignores]);
+			}
+		}
+
+		// @ts-expect-error
+		if (node.ignores) {
+			context.next({
+				...context.state,
+				// @ts-expect-error see below
+				ignores: node.ignores
+			});
+		} else if (context.state.ignores.size > 0) {
+			// @ts-expect-error
+			node.ignores = context.state.ignores;
+		}
+	},
+	Fragment(node, context) {
+		/** @type {string[]} */
+		let ignores = [];
+
+		for (const child of node.nodes) {
+			if (child.type === 'Text' && child.data.trim() === '') {
+				continue;
+			}
+
+			if (child.type === 'Comment') {
+				ignores.push(...extract_svelte_ignore(child.data));
+			} else {
+				const combined_ignores = new Set(context.state.ignores);
+				for (const ignore of ignores) combined_ignores.add(ignore);
+
+				if (combined_ignores.size > 0) {
+					// TODO this is a grotesque hack that's made necessary by the fact that
+					// we can't call `context.visit(...)` here, because we do the convoluted
+					// visitor merging thing. I'm increasingly of the view that we should
+					// rearchitect this stuff and have a single visitor per node. It'd be
+					// more efficient and much simpler.
+					// @ts-expect-error
+					child.ignores = combined_ignores;
+				}
+
+				ignores = [];
+			}
+		}
+	},
 	Attribute(node, context) {
 		if (node.value === true) return;
 
@@ -1142,7 +1210,7 @@ const common_visitors = {
 					binding.kind === 'derived') &&
 				context.state.function_depth === binding.scope.function_depth
 			) {
-				warn(context.state.analysis.warnings, node, context.path, 'static-state-reference');
+				warn(context.state.analysis.warnings, node, 'static-state-reference');
 			}
 		}
 	},

packages/svelte/src/compiler/phases/2-analyze/types.d.ts

@@ -22,6 +22,7 @@ export interface AnalysisState {
 	expression: ExpressionTag | ClassDirective | SpreadAttribute | null;
 	private_derived_state: string[];
 	function_depth: number;
+	ignores: Set<string>;
 }
 
 export interface LegacyAnalysisState extends AnalysisState {