\n * I'm a fade Transition!\n *
\n * )}\n * \n * \n * {state => (\n * // ...\n * )}\n * \n * \n *
\n * );\n * }\n * ```\n *\n * When the button is clicked the component will shift to the `'entering'` state\n * and stay there for 500ms (the value of `timeout`) before it finally switches\n * to `'entered'`.\n *\n * When `in` is `false` the same thing happens except the state moves from\n * `'exiting'` to `'exited'`.\n */\n\nvar Transition =\n/*#__PURE__*/\nfunction (_React$Component) {\n _inheritsLoose(Transition, _React$Component);\n\n function Transition(props, context) {\n var _this;\n\n _this = _React$Component.call(this, props, context) || this;\n var parentGroup = context; // In the context of a TransitionGroup all enters are really appears\n\n var appear = parentGroup && !parentGroup.isMounting ? props.enter : props.appear;\n var initialStatus;\n _this.appearStatus = null;\n\n if (props.in) {\n if (appear) {\n initialStatus = EXITED;\n _this.appearStatus = ENTERING;\n } else {\n initialStatus = ENTERED;\n }\n } else {\n if (props.unmountOnExit || props.mountOnEnter) {\n initialStatus = UNMOUNTED;\n } else {\n initialStatus = EXITED;\n }\n }\n\n _this.state = {\n status: initialStatus\n };\n _this.nextCallback = null;\n return _this;\n }\n\n Transition.getDerivedStateFromProps = function getDerivedStateFromProps(_ref, prevState) {\n var nextIn = _ref.in;\n\n if (nextIn && prevState.status === UNMOUNTED) {\n return {\n status: EXITED\n };\n }\n\n return null;\n }; // getSnapshotBeforeUpdate(prevProps) {\n // let nextStatus = null\n // if (prevProps !== this.props) {\n // const { status } = this.state\n // if (this.props.in) {\n // if (status !== ENTERING && status !== ENTERED) {\n // nextStatus = ENTERING\n // }\n // } else {\n // if (status === ENTERING || status === ENTERED) {\n // nextStatus = EXITING\n // }\n // }\n // }\n // return { nextStatus }\n // }\n\n\n var _proto = Transition.prototype;\n\n _proto.componentDidMount = function componentDidMount() {\n this.updateStatus(true, this.appearStatus);\n };\n\n _proto.componentDidUpdate = function componentDidUpdate(prevProps) {\n var nextStatus = null;\n\n if (prevProps !== this.props) {\n var status = this.state.status;\n\n if (this.props.in) {\n if (status !== ENTERING && status !== ENTERED) {\n nextStatus = ENTERING;\n }\n } else {\n if (status === ENTERING || status === ENTERED) {\n nextStatus = EXITING;\n }\n }\n }\n\n this.updateStatus(false, nextStatus);\n };\n\n _proto.componentWillUnmount = function componentWillUnmount() {\n this.cancelNextCallback();\n };\n\n _proto.getTimeouts = function getTimeouts() {\n var timeout = this.props.timeout;\n var exit, enter, appear;\n exit = enter = appear = timeout;\n\n if (timeout != null && typeof timeout !== 'number') {\n exit = timeout.exit;\n enter = timeout.enter; // TODO: remove fallback for next major\n\n appear = timeout.appear !== undefined ? timeout.appear : enter;\n }\n\n return {\n exit: exit,\n enter: enter,\n appear: appear\n };\n };\n\n _proto.updateStatus = function updateStatus(mounting, nextStatus) {\n if (mounting === void 0) {\n mounting = false;\n }\n\n if (nextStatus !== null) {\n // nextStatus will always be ENTERING or EXITING.\n this.cancelNextCallback();\n var node = ReactDOM.findDOMNode(this);\n\n if (nextStatus === ENTERING) {\n this.performEnter(node, mounting);\n } else {\n this.performExit(node);\n }\n } else if (this.props.unmountOnExit && this.state.status === EXITED) {\n this.setState({\n status: UNMOUNTED\n });\n }\n };\n\n _proto.performEnter = function performEnter(node, mounting) {\n var _this2 = this;\n\n var enter = this.props.enter;\n var appearing = this.context ? this.context.isMounting : mounting;\n var timeouts = this.getTimeouts();\n var enterTimeout = appearing ? timeouts.appear : timeouts.enter; // no enter animation skip right to ENTERED\n // if we are mounting and running this it means appear _must_ be set\n\n if (!mounting && !enter || config.disabled) {\n this.safeSetState({\n status: ENTERED\n }, function () {\n _this2.props.onEntered(node);\n });\n return;\n }\n\n this.props.onEnter(node, appearing);\n this.safeSetState({\n status: ENTERING\n }, function () {\n _this2.props.onEntering(node, appearing);\n\n _this2.onTransitionEnd(node, enterTimeout, function () {\n _this2.safeSetState({\n status: ENTERED\n }, function () {\n _this2.props.onEntered(node, appearing);\n });\n });\n });\n };\n\n _proto.performExit = function performExit(node) {\n var _this3 = this;\n\n var exit = this.props.exit;\n var timeouts = this.getTimeouts(); // no exit animation skip right to EXITED\n\n if (!exit || config.disabled) {\n this.safeSetState({\n status: EXITED\n }, function () {\n _this3.props.onExited(node);\n });\n return;\n }\n\n this.props.onExit(node);\n this.safeSetState({\n status: EXITING\n }, function () {\n _this3.props.onExiting(node);\n\n _this3.onTransitionEnd(node, timeouts.exit, function () {\n _this3.safeSetState({\n status: EXITED\n }, function () {\n _this3.props.onExited(node);\n });\n });\n });\n };\n\n _proto.cancelNextCallback = function cancelNextCallback() {\n if (this.nextCallback !== null) {\n this.nextCallback.cancel();\n this.nextCallback = null;\n }\n };\n\n _proto.safeSetState = function safeSetState(nextState, callback) {\n // This shouldn't be necessary, but there are weird race conditions with\n // setState callbacks and unmounting in testing, so always make sure that\n // we can cancel any pending setState callbacks after we unmount.\n callback = this.setNextCallback(callback);\n this.setState(nextState, callback);\n };\n\n _proto.setNextCallback = function setNextCallback(callback) {\n var _this4 = this;\n\n var active = true;\n\n this.nextCallback = function (event) {\n if (active) {\n active = false;\n _this4.nextCallback = null;\n callback(event);\n }\n };\n\n this.nextCallback.cancel = function () {\n active = false;\n };\n\n return this.nextCallback;\n };\n\n _proto.onTransitionEnd = function onTransitionEnd(node, timeout, handler) {\n this.setNextCallback(handler);\n var doesNotHaveTimeoutOrListener = timeout == null && !this.props.addEndListener;\n\n if (!node || doesNotHaveTimeoutOrListener) {\n setTimeout(this.nextCallback, 0);\n return;\n }\n\n if (this.props.addEndListener) {\n this.props.addEndListener(node, this.nextCallback);\n }\n\n if (timeout != null) {\n setTimeout(this.nextCallback, timeout);\n }\n };\n\n _proto.render = function render() {\n var status = this.state.status;\n\n if (status === UNMOUNTED) {\n return null;\n }\n\n var _this$props = this.props,\n children = _this$props.children,\n childProps = _objectWithoutPropertiesLoose(_this$props, [\"children\"]); // filter props for Transtition\n\n\n delete childProps.in;\n delete childProps.mountOnEnter;\n delete childProps.unmountOnExit;\n delete childProps.appear;\n delete childProps.enter;\n delete childProps.exit;\n delete childProps.timeout;\n delete childProps.addEndListener;\n delete childProps.onEnter;\n delete childProps.onEntering;\n delete childProps.onEntered;\n delete childProps.onExit;\n delete childProps.onExiting;\n delete childProps.onExited;\n\n if (typeof children === 'function') {\n // allows for nested Transitions\n return React.createElement(TransitionGroupContext.Provider, {\n value: null\n }, children(status, childProps));\n }\n\n var child = React.Children.only(children);\n return (// allows for nested Transitions\n React.createElement(TransitionGroupContext.Provider, {\n value: null\n }, React.cloneElement(child, childProps))\n );\n };\n\n return Transition;\n}(React.Component);\n\nTransition.contextType = TransitionGroupContext;\nTransition.propTypes = process.env.NODE_ENV !== \"production\" ? {\n /**\n * A `function` child can be used instead of a React element. This function is\n * called with the current transition status (`'entering'`, `'entered'`,\n * `'exiting'`, `'exited'`), which can be used to apply context\n * specific props to a component.\n *\n * ```jsx\n *