From ba70cd94d67b6d81a6dd9bea5e8b164495231114 Mon Sep 17 00:00:00 2001
From: Eric Socolofsky <ericsoco@uber.com>
Date: Tue, 23 May 2017 22:29:56 -0700
Subject: [PATCH 1/2] Conditionally require hammer.js to avoid failure on
 server, on `window` and `document` references.

---
 src/utils/events/event-manager.js | 22 +++++++++++++++++-----
 src/utils/events/wheel-input.js   |  3 ++-
 2 files changed, 19 insertions(+), 6 deletions(-)

diff --git a/src/utils/events/event-manager.js b/src/utils/events/event-manager.js
index c4c0a2f84a7..11410ba4590 100644
--- a/src/utils/events/event-manager.js
+++ b/src/utils/events/event-manager.js
@@ -1,13 +1,15 @@
-import {Manager} from 'hammerjs';
+import WheelInput from './wheel-input';
+import MoveInput from './move-input';
 
-import {
+const Manager = (typeof window === 'undefined' || typeof document === 'undefined') ?
+  ManagerMock : require('hammerjs').Manager;
+const {
   BASIC_EVENT_ALIASES,
   EVENT_RECOGNIZER_MAP,
   RECOGNIZERS,
   GESTURE_EVENT_ALIASES
-} from './constants';
-import WheelInput from './wheel-input';
-import MoveInput from './move-input';
+} = (typeof window === 'undefined' || typeof document === 'undefined') ?
+  {} : require('./constants');
 
 /**
  * Single API for subscribing to events about both
@@ -149,3 +151,13 @@ export default class EventManager {
     return event => this.manager.emit(eventAlias, event);
   }
 }
+
+function ManagerMock(m) {
+  const noop = () => {};
+  return {
+    on: noop,
+    off: noop,
+    destroy: noop,
+    emit: noop
+  };
+}
diff --git a/src/utils/events/wheel-input.js b/src/utils/events/wheel-input.js
index d2905aa4d7d..2b2449c2510 100644
--- a/src/utils/events/wheel-input.js
+++ b/src/utils/events/wheel-input.js
@@ -1,4 +1,5 @@
-/* global window:false */
+import window from '../../lib/utils/globals';
+
 const ua = typeof window.navigator !== 'undefined' ?
   window.navigator.userAgent.toLowerCase() : '';
 const firefox = ua.indexOf('firefox') !== -1;

From d2ee12aeda47b4b0ab144041e367709db05593b4 Mon Sep 17 00:00:00 2001
From: Eric Socolofsky <ericsoco@uber.com>
Date: Wed, 24 May 2017 10:37:57 -0700
Subject: [PATCH 2/2] Use `isBrowser` for conditional requires Manually hoist
 ManagerMock ;)

---
 src/utils/events/event-manager.js | 33 ++++++++++++++++++-------------
 1 file changed, 19 insertions(+), 14 deletions(-)

diff --git a/src/utils/events/event-manager.js b/src/utils/events/event-manager.js
index 11410ba4590..e00c118eb9c 100644
--- a/src/utils/events/event-manager.js
+++ b/src/utils/events/event-manager.js
@@ -1,15 +1,30 @@
 import WheelInput from './wheel-input';
 import MoveInput from './move-input';
+import {isBrowser} from '../../controllers/globals';
+
+// Hammer.js directly references `document` and `window`,
+// which means that importing it in environments without
+// those objects throws errors. Therefore, instead of
+// directly `import`ing 'hammerjs' and './constants'
+// (which imports Hammer.js) we conditionally require it
+// depending on support for those globals.
+function ManagerMock(m) {
+  const noop = () => {};
+  return {
+    on: noop,
+    off: noop,
+    destroy: noop,
+    emit: noop
+  };
+}
 
-const Manager = (typeof window === 'undefined' || typeof document === 'undefined') ?
-  ManagerMock : require('hammerjs').Manager;
+const Manager = isBrowser ? require('hammerjs').Manager : ManagerMock;
 const {
   BASIC_EVENT_ALIASES,
   EVENT_RECOGNIZER_MAP,
   RECOGNIZERS,
   GESTURE_EVENT_ALIASES
-} = (typeof window === 'undefined' || typeof document === 'undefined') ?
-  {} : require('./constants');
+} = isBrowser ? require('./constants') : {};
 
 /**
  * Single API for subscribing to events about both
@@ -151,13 +166,3 @@ export default class EventManager {
     return event => this.manager.emit(eventAlias, event);
   }
 }
-
-function ManagerMock(m) {
-  const noop = () => {};
-  return {
-    on: noop,
-    off: noop,
-    destroy: noop,
-    emit: noop
-  };
-}