Merge a37babf into 5c70226

Tinkoff · Mar 30, 2020 · 19a31ef · 19a31ef
2 parents 5c70226 + a37babf
commit 19a31ef
Showing 1 changed file with 9 additions and 4 deletions.
diff --git a/projects/ng-dompurify/src/lib/utils/createUponSanitizeElementHook.ts b/projects/ng-dompurify/src/lib/utils/createUponSanitizeElementHook.ts
@@ -3,15 +3,15 @@ import {SanitizeStyle} from '../types/sanitize-style';
 import {addCSSRules} from './addCSSRules';
 
 /**
- * uponSanitizeElementHook factory to sanitize CSS rules from HTMLStyleElement through custom function
+ * uponSanitizeElementHook factory to sanitize CSS rules from
+ * HTMLStyleElement/SVGStyleElement through custom function
  */
 export function createUponSanitizeElementHook(
     sanitizeStyle: SanitizeStyle,
 ): DompurifyHook {
     return node => {
-        if (node instanceof HTMLStyleElement || node instanceof SVGStyleElement) {
-            // https://github.com/microsoft/TypeScript/issues/36896
-            const {sheet} = node as HTMLStyleElement;
+        if (isStyleTag(node)) {
+            const {sheet} = node;
 
             if (sheet instanceof CSSStyleSheet) {
                 node.textContent = addCSSRules(sheet.cssRules, sanitizeStyle).join('\n');
@@ -21,3 +21,8 @@ export function createUponSanitizeElementHook(
         }
     };
 }
+
+// Technically it can also be SVGStyleElement but it just complicates types and fails in SSR
+function isStyleTag(node: Node): node is HTMLStyleElement {
+    return 'sheet' in node;
+}