Bootstrap/js/src/dom/data.js

/**
 * --------------------------------------------------------------------------
 * Bootstrap (v5.0.1): dom/data.js
 * Licensed under MIT (https://github.com/twbs/bootstrap/blob/main/LICENSE)
 * --------------------------------------------------------------------------
 */

/**
 * ------------------------------------------------------------------------
 * Constants
 * ------------------------------------------------------------------------
 */

const elementMap = new Map()

export default {
  set(element, key, instance) {
    if (!elementMap.has(element)) {
      elementMap.set(element, new Map())
    }

    const instanceMap = elementMap.get(element)

    // make it clear we only want one instance per element
    // can be removed later when multiple key/instances are fine to be used
    if (!instanceMap.has(key) && instanceMap.size !== 0) {
      // eslint-disable-next-line no-console
      console.error(`Bootstrap doesn't allow more than one instance per element. Bound instance: ${Array.from(instanceMap.keys())[0]}.`)
      return
    }

    instanceMap.set(key, instance)
  },

  get(element, key) {
    if (elementMap.has(element)) {
      return elementMap.get(element).get(key) || null
    }

    return null
  },

  remove(element, key) {
    if (!elementMap.has(element)) {
      return
    }

    const instanceMap = elementMap.get(element)

    instanceMap.delete(key)

    // free up element references if there are no instances left for an element
    if (instanceMap.size === 0) {
      elementMap.delete(element)
    }
  }
}