[fixed] respect closeTimeoutMS during unmount

Fixes issue #17: "When the modal is unmounted, it will abruptly close,
not waiting for any animations to finish."

The bug was caused by the Modal component unmounting the portal
immediately in `componentWillUnmount` regardless of whether the portal
is currently closing or would animate to close.

Now when a Modal has a non-zero `closeTimeoutMS`, the Modal inspects the
portal state before closing.  If the portal is open or closing, but not
closed, it waits to unmount the portal.  If the portal is open and not
already closing, the Modal calls closeWithTimeout() to trigger the
close.

Adds test to ensure portal DOM persists after Modal is unmounted when
the Modal has a `closeTimeoutMS` set.  Updates existing tests to
properly unmount test Modal instances.

lib/components/Modal.js

@@ -83,6 +83,24 @@ var Modal = React.createClass({
       ariaAppHider.show(this.props.appElement);
     }
 
+    var state = this.portal.state;
+    var now = Date.now();
+    var closesAt = state.isOpen && this.props.closeTimeoutMS
+      && (state.closesAt
+        || now + this.props.closeTimeoutMS);
+
+    if (closesAt) {
+      if (!state.beforeClose) {
+        this.portal.closeWithTimeout();
+      }
+
+      setTimeout(this.removePortal.bind(this), closesAt - now);
+    } else {
+      this.removePortal();
+    }
+  },
+
+  removePortal () {
     ReactDOM.unmountComponentAtNode(this.node);
     var parent = getParentElement(this.props.parentSelector);
     parent.removeChild(this.node);

lib/components/ModalPortal.js

@@ -109,8 +109,9 @@ var ModalPortal = module.exports = React.createClass({
   },
 
   closeWithTimeout: function() {
-    this.setState({beforeClose: true}, function() {
-      this.closeTimer = setTimeout(this.closeWithoutTimeout, this.props.closeTimeoutMS);
+    var closesAt = Date.now() + this.props.closeTimeoutMS;
+    this.setState({beforeClose: true, closesAt: closesAt}, function() {
+      this.closeTimer = setTimeout(this.closeWithoutTimeout, this.state.closesAt - Date.now());
     }.bind(this));
   },
 
@@ -119,7 +120,8 @@ var ModalPortal = module.exports = React.createClass({
       beforeClose: false,
       isOpen: false,
       afterOpen: false,
-    }, function () { this.afterClose() }.bind(this))
+      closesAt: null
+    }, this.afterClose);
   },
 
   handleKeyDown: function(event) {
@@ -158,7 +160,7 @@ var ModalPortal = module.exports = React.createClass({
   },
 
   shouldBeClosed: function() {
-    return !this.props.isOpen && !this.state.beforeClose;
+    return !this.state.isOpen && !this.state.beforeClose;
   },
 
   contentHasFocus: function() {

specs/Modal.spec.js

@@ -9,7 +9,13 @@ const Simulate = TestUtils.Simulate;
 import sinon from 'sinon';
 import expect from 'expect';
 
-describe('Modal', function () {
+describe('Modal', () => {
+  afterEach('check if test cleaned up rendered modals', function () {
+    var overlay = document.querySelectorAll('.ReactModal__Overlay');
+    var content = document.querySelectorAll('.ReactModal__Content');
+    expect(overlay.length).toBe(0);
+    expect(content.length).toBe(0);
+  });
 
   it('scopes tab navigation to the modal');
   it('focuses the last focused element when tabbing in from browser chrome');
@@ -116,7 +122,7 @@ describe('Modal', function () {
         unmountModal();
         done();
       }
-    }, null, function () {});
+    }, null);
 
     renderModal({
       isOpen: true,
@@ -174,6 +180,7 @@ describe('Modal', function () {
         preventDefault: function() { tabPrevented = true; }
     });
     expect(tabPrevented).toEqual(true);
+    unmountModal();
   });
 
   it('supports portalClassName', function () {
@@ -236,15 +243,16 @@ describe('Modal', function () {
   });
 
   it('adds class to body when open', function() {
-    renderModal({isOpen: false});
+    renderModal({ isOpen: false });
     expect(document.body.className.indexOf('ReactModal__Body--open') !== -1).toEqual(false);
+    unmountModal();
 
-    renderModal({isOpen: true});
-    expect(document.body.className.indexOf('ReactModal__Body--open')  !== -1).toEqual(true);
-
-    renderModal({isOpen: false});
-    expect(document.body.className.indexOf('ReactModal__Body--open')  !== -1).toEqual(false);
+    renderModal({ isOpen: true });
+    expect(document.body.className.indexOf('ReactModal__Body--open') !== -1).toEqual(true);
     unmountModal();
+
+    renderModal({ isOpen: false });
+    expect(document.body.className.indexOf('ReactModal__Body--open') !== -1).toEqual(false);
   });
 
   it('removes class from body when unmounted without closing', function() {
@@ -441,26 +449,50 @@ describe('Modal', function () {
     expect(event.constructor.name).toEqual('SyntheticEvent');
   });
 
-  //it('adds --before-close for animations', function() {
-    //var node = document.createElement('div');
-
-    //var component = ReactDOM.render(React.createElement(Modal, {
-      //isOpen: true,
-      //ariaHideApp: false,
-      //closeTimeoutMS: 50,
-    //}), node);
-
-    //component = ReactDOM.render(React.createElement(Modal, {
-      //isOpen: false,
-      //ariaHideApp: false,
-      //closeTimeoutMS: 50,
-    //}), node);
-
-    // It can't find these nodes, I didn't spend much time on this
-    //var overlay = document.querySelector('.ReactModal__Overlay');
-    //var content = document.querySelector('.ReactModal__Content');
-    //ok(overlay.className.match(/ReactModal__Overlay--before-close/));
-    //ok(content.className.match(/ReactModal__Content--before-close/));
-    //unmountModal();
-  //});
+  it('adds --before-close for animations', () => {
+    const closeTimeoutMS = 50;
+    const modal = renderModal({
+      isOpen: true,
+      closeTimeoutMS
+    });
+
+    modal.portal.closeWithTimeout();
+
+    const overlay = TestUtils.findRenderedDOMComponentWithClass(modal.portal, 'ReactModal__Overlay');
+    const content = TestUtils.findRenderedDOMComponentWithClass(modal.portal, 'ReactModal__Content');
+
+    expect(/ReactModal__Overlay--before-close/.test(overlay.className)).toBe(true);
+    expect(/ReactModal__Content--before-close/.test(content.className)).toBe(true);
+
+    modal.portal.closeWithoutTimeout();
+    unmountModal();
+  });
+
+  it('keeps the modal in the DOM until closeTimeoutMS elapses', (done) => {
+    const closeTimeoutMS = 50;
+
+    renderModal({
+      isOpen: true,
+      closeTimeoutMS
+    });
+
+    unmountModal();
+
+    const checkDOM = (expectMounted) => {
+      const overlay = document.querySelectorAll('.ReactModal__Overlay');
+      const content = document.querySelectorAll('.ReactModal__Content');
+      const numNodes = expectMounted ? 1 : 0;
+      expect(overlay.length).toBe(numNodes);
+      expect(content.length).toBe(numNodes);
+    };
+
+    // content is still mounted after modal is gone
+    checkDOM(true);
+
+    setTimeout(() => {
+      // content is unmounted after specified timeout
+      checkDOM(false);
+      done();
+    }, closeTimeoutMS);
+  });
 });