fix(BpkBottomSheet): clear close-animation timer on unmount

packages/backpack-web/src/bpk-component-bottom-sheet/src/BpkBottomSheet-test.tsx

@@ -240,6 +240,28 @@ describe('BpkBottomSheet', () => {
     expect(titleEl).toBeInTheDocument();
   });
 
+  it('does not call onClose after unmount (timer leak regression)', () => {
+    jest.useFakeTimers();
+    const onClose = jest.fn();
+    const { unmount } = render(
+      <BpkBottomSheet
+        ariaLabelledby="bottom-sheet"
+        closeLabel="Close"
+        id="my-bottom-sheet"
+        isOpen
+        onClose={onClose}
+      >
+        Content
+      </BpkBottomSheet>,
+    );
+    // Simulate close button click would normally schedule a 240ms timer.
+    // Unmounting before the timer fires should cancel it.
+    unmount();
+    jest.advanceTimersByTime(300);
+    expect(onClose).not.toHaveBeenCalled();
+    jest.useRealTimers();
+  });
+
   it('adds correct id to custom title element for aria-labelledby reference', () => {
     const { container } = render(
       <BpkBottomSheet

packages/backpack-web/src/bpk-component-bottom-sheet/src/BpkBottomSheet.tsx

@@ -16,7 +16,7 @@
  * limitations under the License.
  */
 import type { SyntheticEvent, ReactNode, ReactElement } from 'react';
-import { useCallback, useState, isValidElement, cloneElement } from 'react';
+import { useCallback, useEffect, useRef, useState, isValidElement, cloneElement } from 'react';
 
 import BpkBreakpoint, { BREAKPOINTS } from '../../bpk-component-breakpoint';
 // @ts-expect-error Untyped import. See `decisions/imports-ts-suppressions.md`.
@@ -130,9 +130,19 @@ const BpkBottomSheet = ({
   isAboveMobile: boolean;
 }) => {
   const [exiting, setExiting] = useState(false);
+  const closeTimerRef = useRef<ReturnType<typeof setTimeout> | null>(null);
 
   const animationTimeout = 240;
 
+  useEffect(
+    () => () => {
+      if (closeTimerRef.current !== null) {
+        clearTimeout(closeTimerRef.current);
+      }
+    },
+    [],
+  );
+
   const handleClose = useCallback(
     (
       arg0?:
@@ -147,7 +157,7 @@ const BpkBottomSheet = ({
       const timeoutDuration = isAboveMobile ? 0 : animationTimeout;
 
       setExiting(true);
-      setTimeout(() => {
+      closeTimerRef.current = setTimeout(() => {
         onClose(arg0, arg1);
         setExiting(false);
       }, timeoutDuration);