From e7fa0ea5253a89460c2021a53dbebaa4ff4ce38f Mon Sep 17 00:00:00 2001
From: Dan Hayden <dan@tutonics.com>
Date: Wed, 26 Jul 2017 15:52:15 +0100
Subject: [PATCH] fix: use Number.isFinite polyfill to fix IE11 compatibility

---
 package.json                   |  2 +-
 src/pick-by-weight.js          | 16 ++++++++++++++++
 src/react-simple-experiment.js |  4 ++--
 3 files changed, 19 insertions(+), 3 deletions(-)
 create mode 100644 src/pick-by-weight.js

diff --git a/package.json b/package.json
index 6c86fac..83ed71e 100644
--- a/package.json
+++ b/package.json
@@ -39,8 +39,8 @@
     "react": "^15.0.0-0"
   },
   "dependencies": {
+    "is-finite": "1.0.2",
     "localforage": "1.5.0",
-    "pick-one-by-weight": "1.0.2",
     "prop-types": "15.5.10"
   },
   "devDependencies": {
diff --git a/src/pick-by-weight.js b/src/pick-by-weight.js
new file mode 100644
index 0000000..a74d4e7
--- /dev/null
+++ b/src/pick-by-weight.js
@@ -0,0 +1,16 @@
+import isFinite from 'is-finite'
+
+export default function pickOneByWeight (anObj) {
+  let _keys = Object.keys(anObj)
+  const sum = _keys.reduce((p, c) => p + anObj[c], 0)
+  if (!isFinite(sum)) {
+    throw new Error('All values in object must be a numeric value')
+  }
+  let choose = ~~(Math.random() * sum)
+  for (let i = 0, count = 0; i < _keys.length; i++) {
+    count += anObj[_keys[i]]
+    if (count > choose) {
+      return _keys[i]
+    }
+  }
+}
diff --git a/src/react-simple-experiment.js b/src/react-simple-experiment.js
index fcddb76..192f734 100644
--- a/src/react-simple-experiment.js
+++ b/src/react-simple-experiment.js
@@ -1,6 +1,6 @@
 import React from 'react'
 import PropTypes from 'prop-types'
-import pickOneByWeight from 'pick-one-by-weight'
+import pickByWeight from './pick-by-weight'
 import Storage from './storage'
 
 const storage = Storage({name: 'react-simple-experiment'})
@@ -31,7 +31,7 @@ export class Experiment extends React.Component {
 
     storage.getItem(storageName).then(variant => {
       if (!variant || !variantNames.includes(variant) || data[variant] < 1) {
-        variant = pickOneByWeight(data)
+        variant = pickByWeight(data)
         storage.setItem(storageName, variant)
       }