optimize literals

Author: adiguba

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

@@ -1,6 +1,7 @@
 /** @import { Expression, Identifier, ObjectExpression } from 'estree' */
 /** @import { AST, ExpressionMetadata } from '#compiler' */
 /** @import { ComponentClientTransformState, ComponentContext } from '../../types' */
+import { escape_html } from '../../../../../../escaping.js';
 import { normalize_attribute } from '../../../../../../utils.js';
 import { is_ignored } from '../../../../../state.js';
 import { is_event_attribute } from '../../../../../utils/ast.js';
@@ -241,6 +242,8 @@ export function build_set_class(
 	if (element.metadata.scoped && context.state.analysis.css.hash) {
 		if (value.type === 'Literal' && (value.value === '' || value.value === null)) {
 			value = b.literal(context.state.analysis.css.hash);
+		} else if (value.type === 'Literal' && typeof value.value === 'string') {
+			value = b.literal(escape_html(value.value, true) + ' ' + context.state.analysis.css.hash);
 		} else {
 			css_hash = b.literal(context.state.analysis.css.hash);
 		}

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

@@ -421,9 +421,13 @@ function build_to_class(hash, class_directives, class_attribute) {
 		hash &&
 		!classes &&
 		class_name.type === 'Literal' &&
-		(class_name.value === null || class_name.value === '')
+		(class_name.value === null || class_name.value === '' || typeof class_name.value === 'string')
 	) {
-		expression = b.literal(hash);
+		if (class_name.value === null || class_name.value === '') {
+			expression = b.literal(hash);
+		} else {
+			expression = b.literal(escape_html(class_name.value, true) + ' ' + hash);
+		}
 	} else {
 		expression = b.call('$.to_class', class_name, b.literal(hash), classes);
 	}