SSENSE/vue-carousel

Bug: Missing cleanup of resize listener

Open

#385 opened on Mar 11, 2019

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buggood first issue

Description

Bug Report

Currently in the mounted() hook of Carousel.vue, an event listener is attached to window,

  window.addEventListener(
    "resize",
    debounce(this.onResize, this.refreshRate)
  );

But there is no equivalent removeEventListener call in the beforeDestroy() hook.

  beforeDestroy() {
    this.detachMutationObserver();
    window.removeEventListener("resize", this.getBrowserWidth);
    this.$refs["VueCarousel-inner"].removeEventListener(
      this.transitionstart,
      this.handleTransitionStart
    );
    this.$refs["VueCarousel-inner"].removeEventListener(
      this.transitionend,
      this.handleTransitionEnd
    );
    this.$refs["VueCarousel-wrapper"].removeEventListener(
      this.isTouch ? "touchstart" : "mousedown",
      this.onStart
    );
  }

This results in a buildup of listeners on the window object when a page is navigated to and away from multiple times via routing.

Contributor guide

Tech stack
vuejavascripthtmlcss
Domain
frontend
Issue type
bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
under 1 hour
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
stale
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
clear
Prerequisites
Basic Vue.jsEvent listener cleanupLifecycle hooks
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
85
Research direction
The bug is in Carousel.vue. In the mounted() hook, a resize listener is added via window.addEventListener. In the beforeDestroy() hook, add the corresponding window.removeEventListener for the same function reference (debounce(this.onResize, this.refreshRate)). Ensure that the debounced function is stored or referenced correctly to avoid mismatches. No linked PRs or comments provide a fix, so the solution is straightforward.