addEventListener()

in packages/shared/src/event.ts [168:203]

• 36 lines of code
• 13 McCabe index (conditional complexity)

  addEventListener(type: any, listener: any, options: any) {
    const target = this.eventTarget(type)
    if (isOnlyMode(options?.mode)) {
      target[EVENTS_ONCE_SYMBOL] = target[EVENTS_ONCE_SYMBOL] || {}
      const constructor = this['constructor']
      constructor[EVENTS_ONCE_SYMBOL] = constructor[EVENTS_ONCE_SYMBOL] || {}
      const handler = target[EVENTS_ONCE_SYMBOL][type]
      const container = constructor[EVENTS_ONCE_SYMBOL][type]
      if (!handler) {
        if (container) {
          if (options.mode === 'onlyChild') {
            if (container.contains(target)) {
              container.removeEventListener(
                type,
                container[EVENTS_ONCE_SYMBOL][type],
                options
              )
              delete container[EVENTS_ONCE_SYMBOL][type]
            }
          } else if (options.mode === 'onlyParent') {
            if (container.contains(target)) return
          }
        }
        target.addEventListener(type, listener, options)
        target[EVENTS_ONCE_SYMBOL][type] = listener
        constructor[EVENTS_ONCE_SYMBOL][type] = target
      }
    } else {
      target[EVENTS_SYMBOL] = target[EVENTS_SYMBOL] || {}
      target[EVENTS_SYMBOL][type] = target[EVENTS_SYMBOL][type] || new Map()
      if (!target[EVENTS_SYMBOL][type]?.get?.(listener)) {
        target.addEventListener(type, listener, options)
        target[EVENTS_SYMBOL][type]?.set?.(listener, true)
      }
    }
  }