From d544024ca2fcabb679a4e78337a269824360b606 Mon Sep 17 00:00:00 2001
From: quiaro <quiaro@gmail.com>
Date: Tue, 18 Jul 2017 19:26:36 -0600
Subject: [PATCH] [Popover] Doesn't reposition with anchorEl

Closes #5937
---
 src/internal/Popover.js      | 31 ++++++++++++++++++++++++++-----
 src/internal/Popover.spec.js | 29 ++++++++++++++++++++++++++++-
 2 files changed, 54 insertions(+), 6 deletions(-)

diff --git a/src/internal/Popover.js b/src/internal/Popover.js
index 6e170fe1f76af2..fe68cb89aeb759 100644
--- a/src/internal/Popover.js
+++ b/src/internal/Popover.js
@@ -2,9 +2,12 @@
 
 import React, { Component } from 'react';
 import type { Element } from 'react';
+import ReactDOM from 'react-dom';
 import classNames from 'classnames';
 import { createStyleSheet } from 'jss-theme-reactor';
 import contains from 'dom-helpers/query/contains';
+import debounce from 'lodash/debounce';
+import EventListener from 'react-event-listener';
 import withStyles from '../styles/withStyles';
 import customPropTypes from '../utils/customPropTypes';
 import Modal from './Modal';
@@ -211,7 +214,22 @@ class Popover extends Component<DefaultProps, Props, void> {
     return `scale(${value}, ${value ** 2})`;
   }
 
+  componentWillUnmount = () => {
+    this.handleResize.cancel();
+  };
+
   autoTransitionDuration = undefined;
+  transitionEl = undefined;
+
+  setPositioningStyles = (element: HTMLElement) => {
+    if (element && element.style) {
+      const positioning = this.getPositioningStyle(element);
+
+      element.style.top = positioning.top;
+      element.style.left = positioning.left;
+      element.style.transformOrigin = positioning.transformOrigin;
+    }
+  };
 
   handleEnter = (element: HTMLElement) => {
     element.style.opacity = '0';
@@ -221,11 +239,7 @@ class Popover extends Component<DefaultProps, Props, void> {
       this.props.onEnter(element);
     }
 
-    const positioning = this.getPositioningStyle(element);
-
-    element.style.top = positioning.top;
-    element.style.left = positioning.left;
-    element.style.transformOrigin = positioning.transformOrigin;
+    this.setPositioningStyles(element);
 
     let { transitionDuration } = this.props;
     const { transitions } = this.context.styleManager.theme;
@@ -281,6 +295,11 @@ class Popover extends Component<DefaultProps, Props, void> {
     }
   };
 
+  handleResize = debounce(() => {
+    const element: any = ReactDOM.findDOMNode(this.transitionEl);
+    this.setPositioningStyles(element);
+  }, 166);
+
   handleRequestTimeout = () => {
     if (this.props.transitionDuration === 'auto') {
       return (this.autoTransitionDuration || 0) + 20;
@@ -437,6 +456,7 @@ class Popover extends Component<DefaultProps, Props, void> {
           role={role}
           onRequestTimeout={this.handleRequestTimeout}
           transitionAppear
+          ref={node => (this.transitionEl = node)}
         >
           <Paper
             data-mui-test="Popover"
@@ -444,6 +464,7 @@ class Popover extends Component<DefaultProps, Props, void> {
             elevation={elevation}
             {...other}
           >
+            <EventListener target="window" onResize={this.handleResize} />
             {children}
           </Paper>
         </Transition>
diff --git a/src/internal/Popover.spec.js b/src/internal/Popover.spec.js
index 95530767429fb0..cfc993908cb83a 100644
--- a/src/internal/Popover.spec.js
+++ b/src/internal/Popover.spec.js
@@ -2,7 +2,7 @@
 
 import React from 'react';
 import { assert } from 'chai';
-import { spy, stub } from 'sinon';
+import { spy, stub, useFakeTimers } from 'sinon';
 import css from 'dom-helpers/style';
 import { createShallow, createMount } from '../test-utils';
 import Popover, { styleSheet } from './Popover';
@@ -416,6 +416,33 @@ describe('<Popover />', () => {
     });
   });
 
+  describe('on window resize', () => {
+    let clock;
+
+    before(() => {
+      clock = useFakeTimers();
+    });
+
+    after(() => {
+      clock.restore();
+    });
+
+    it('should recalculate position if the popover is open', () => {
+      const wrapper = shallow(<Popover open transitionDuration={0} />);
+      const instance = wrapper.instance();
+
+      stub(instance, 'setPositioningStyles');
+      wrapper.find('EventListener').at(0).simulate('resize');
+      clock.tick(166);
+      assert.isTrue(instance.setPositioningStyles.called, 'position styles recalculated');
+    });
+
+    it('should not recalculate position if the popover is closed', () => {
+      const wrapper = mount(<Popover transitionDuration={0} />);
+      assert.isNotTrue(wrapper.contains('EventListener'), 'no component listening on resize');
+    });
+  });
+
   describe('getPositioningStyle(element)', () => {
     let instance;
     let element;