validate-options.js

import {
  isPlainObject,
  isFunctionalComponent,
  isConstructor
} from './validators'
import { VUE_VERSION } from './consts'
import { compileTemplateForSlots } from './compile-template'
import { throwError } from './util'
import { validateSlots } from './validate-slots'

function vueExtendUnsupportedOption (option) {
  return `options.${option} is not supported for ` +
  `components created with Vue.extend in Vue < 2.3. ` +
  `You can set ${option} to false to mount the component.`
}
// these options aren't supported if Vue is version < 2.3
// for components using Vue.extend. This is due to a bug
// that means the mixins we use to add properties are not applied
// correctly
const UNSUPPORTED_VERSION_OPTIONS = [
  'mocks',
  'stubs',
  'localVue'
]

export function validateOptions (options, component) {
  if (options.parentComponent && !isPlainObject(options.parentComponent)) {
    throwError(
      `options.parentComponent should be a valid Vue component options object`
    )
  }

  if (!isFunctionalComponent(component) && options.context) {
    throwError(
      `mount.context can only be used when mounting a functional component`
    )
  }

  if (options.context && !isPlainObject(options.context)) {
    throwError('mount.context must be an object')
  }

  if (
    VUE_VERSION < 2.3 && isConstructor(component)
  ) {
    UNSUPPORTED_VERSION_OPTIONS.forEach((option) => {
      if (options[option]) {
        throwError(vueExtendUnsupportedOption(option))
      }
    })
  }

  if (options.slots) {
    compileTemplateForSlots(options.slots)
    // validate slots outside of the createSlots function so
    // that we can throw an error without it being caught by
    // the Vue error handler
    // $FlowIgnore
    validateSlots(options.slots)
  }
}