fix(user-interaction): handle null listener in addEventListener (open…

…-telemetry#765) Co-authored-by: Valentin Marchaud <contact@vmarchaud.fr>
intercom · Dec 5, 2021 · aacfe82 · aacfe82
1 parent 686c3e7
commit aacfe82
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Showing 2 changed files with 18 additions and 5 deletions.
diff --git a/plugins/web/opentelemetry-instrumentation-user-interaction/src/instrumentation.ts b/plugins/web/opentelemetry-instrumentation-user-interaction/src/instrumentation.ts
@@ -259,14 +259,19 @@ export class UserInteractionInstrumentation extends InstrumentationBase<unknown>
    */
   private _patchAddEventListener() {
     const plugin = this;
-    return (original: Function) => {
+    return (original: EventTarget['addEventListener']) => {
       return function addEventListenerPatched(
         this: HTMLElement,
-        type: any,
-        listener: any,
-        useCapture: any
+        type: string,
+        listener: EventListenerOrEventListenerObject | null,
+        useCapture?: boolean | AddEventListenerOptions
       ) {
-        const once = useCapture && useCapture.once;
+        // Forward calls with listener = null
+        if (!listener) {
+          return original.call(this, type, listener, useCapture);
+        }
+
+        const once = typeof useCapture === 'object' && useCapture.once;
         const patchedListener = function (this: HTMLElement, ...args: any[]) {
           let parentSpan: api.Span | undefined;
           const event: Event | undefined = args[0];

diff --git a/...ns/web/opentelemetry-instrumentation-user-interaction/test/userInteraction.nozone.test.ts b/...ns/web/opentelemetry-instrumentation-user-interaction/test/userInteraction.nozone.test.ts
@@ -546,6 +546,14 @@ describe('UserInteractionInstrumentation', () => {
       });
     });
 
+    it('should handle null event listener argument', () => {
+      // @ts-expect-error Typescript typings report null listener as error
+      // while allowed by EventTarget['addEventListener'] and js engines
+      document.addEventListener('click', null);
+      // @ts-expect-error see above
+      document.removeEventListener('click', null);
+    });
+
     it('should handle disable', () => {
       assert.strictEqual(
         isWrapped(HTMLElement.prototype.addEventListener),