Function updateComponent

packages/nerv/src/lifecycle.ts:225–301

(component, isForce = false)

}

export function updateComponent (component, isForce = false) {
  let vnode = component.vnode
  let dom = vnode.dom
  const props = component.props
  let state = component.getState()
  const context = component.context
  const prevProps = component.prevProps || props
  const prevState = component.prevState || component.state
  const prevContext = component.prevContext || context

  const stateFromProps = callGetDerivedStateFromProps(props, state, component)

  if (!isUndefined(stateFromProps)) {
    state = stateFromProps
  }

  component.props = prevProps
  component.context = prevContext
  let skip = false
  const onSCU = props.onShouldComponentUpdate
  if (
    !isForce &&
    (
      (isFunction(component.shouldComponentUpdate) &&
      callShouldComponentUpdate(props, state, context, component) === false) ||
      (isFunction(onSCU) && onSCU(prevProps, props) === false)
    )
  ) {
    skip = true
  } else if (!hasNewLifecycle(component) && isFunction(component.componentWillUpdate)) {
    errorCatcher(() => {
      component.componentWillUpdate(props, state, context)
    }, component)
  }

  if (!isUndefined(stateFromProps)) {
    component.state = stateFromProps
  }

  component.props = props
  component.state = state
  component.context = context
  component._dirty = false
  if (!skip) {
    const lastRendered = component._rendered
    const rendered = renderComponent(component)
    rendered.parentVNode = vnode
    const childContext = getChildContext(component, context)
    const snapshot = callGetSnapshotBeforeUpdate(prevProps, prevState, component)
    let parentDom = lastRendered.dom && lastRendered.dom.parentNode
    if (isArray(lastRendered)) {
      const hostNode = getFragmentHostNode(lastRendered)
      if (hostNode != null) {
        parentDom = (lastRendered as any).dom = hostNode.parentNode
      }
    }
    dom = vnode.dom = patch(lastRendered, rendered, parentDom || null, childContext)
    component._rendered = rendered