_valueToNodeAttribute converts the empty string to `trustedTypes.em…

…ptyScript` before setting, if available.
Polymer · Jun 1, 2022 · d69041c · d69041c
1 parent ce474db
commit d69041c
Showing 1 changed file with 8 additions and 4 deletions.
diff --git a/lib/mixins/properties-changed.js b/lib/mixins/properties-changed.js
@@ -531,7 +531,13 @@ export const PropertiesChanged = dedupingMixin(
       if (str === undefined) {
         node.removeAttribute(attribute);
       } else {
-        node.setAttribute(attribute, str);
+        node.setAttribute(
+            attribute,
+            // Closure's type for `setAttribute`'s second parameter incorrectly
+            // excludes `TrustedScript`.
+            (str === '' && window.trustedTypes) ?
+                /** @type {?} */ (window.trustedTypes.emptyScript) :
+                str);
       }
     }
 
@@ -550,9 +556,7 @@ export const PropertiesChanged = dedupingMixin(
     _serializeValue(value) {
       switch (typeof value) {
         case 'boolean':
-          return value ?
-              (window.trustedTypes ? window.trustedTypes.emptyScript : '') :
-              undefined;
+          return value ? '' : undefined;
         default:
           return value != null ? value.toString() : undefined;
       }