From f5a908584c5f6325f10c8c9039e23d34c546e53e Mon Sep 17 00:00:00 2001
From: Oliver foster <oliver.foster@kineo.com>
Date: Thu, 19 Dec 2019 10:02:14 +0000
Subject: [PATCH 01/12] fixes #359 IE11 Added Array.prototype.find and
 Object.assign polyfills

---
 src/parser.js | 16 ++++++++--------
 src/utils.js  | 38 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 46 insertions(+), 8 deletions(-)

diff --git a/src/parser.js b/src/parser.js
index 1b3681f..9f90f0a 100644
--- a/src/parser.js
+++ b/src/parser.js
@@ -82,7 +82,7 @@ class Parser {
   parseBrowser() {
     this.parsedResult.browser = {};
 
-    const browserDescriptor = browserParsersList.find((_browser) => {
+    const browserDescriptor = Utils.find(browserParsersList, _browser => {
       if (typeof _browser.test === 'function') {
         return _browser.test(this);
       }
@@ -165,7 +165,7 @@ class Parser {
   parseOS() {
     this.parsedResult.os = {};
 
-    const os = osParsersList.find((_os) => {
+    const os = Utils.find(osParsersList, _os => {
       if (typeof _os.test === 'function') {
         return _os.test(this);
       }
@@ -241,7 +241,7 @@ class Parser {
   parsePlatform() {
     this.parsedResult.platform = {};
 
-    const platform = platformParsersList.find((_platform) => {
+    const platform = Utils.find(platformParsersList, _platform => {
       if (typeof _platform.test === 'function') {
         return _platform.test(this);
       }
@@ -292,7 +292,7 @@ class Parser {
   parseEngine() {
     this.parsedResult.engine = {};
 
-    const engine = enginesParsersList.find((_engine) => {
+    const engine = Utils.find(enginesParsersList, _engine => {
       if (typeof _engine.test === 'function') {
         return _engine.test(this);
       }
@@ -328,7 +328,7 @@ class Parser {
    * @return {ParsedResult}
    */
   getResult() {
-    return Object.assign({}, this.parsedResult);
+    return Utils.assign({}, this.parsedResult);
   }
 
   /**
@@ -370,7 +370,7 @@ class Parser {
 
     if (platformsAndOSCounter > 0) {
       const platformsAndOSNames = Object.keys(platformsAndOSes);
-      const OSMatchingDefinition = platformsAndOSNames.find(name => (this.isOS(name)));
+      const OSMatchingDefinition = Utils.find(platformsAndOSNames, name => (this.isOS(name)));
 
       if (OSMatchingDefinition) {
         const osResult = this.satisfies(platformsAndOSes[OSMatchingDefinition]);
@@ -380,7 +380,7 @@ class Parser {
         }
       }
 
-      const platformMatchingDefinition = platformsAndOSNames.find(name => (this.isPlatform(name)));
+      const platformMatchingDefinition = Utils.find(platformsAndOSNames, name => (this.isPlatform(name)));
       if (platformMatchingDefinition) {
         const platformResult = this.satisfies(platformsAndOSes[platformMatchingDefinition]);
 
@@ -392,7 +392,7 @@ class Parser {
 
     if (browsersCounter > 0) {
       const browserNames = Object.keys(browsers);
-      const matchingDefinition = browserNames.find(name => (this.isBrowser(name, true)));
+      const matchingDefinition = Utils.find(browserNames, name => (this.isBrowser(name, true)));
 
       if (matchingDefinition !== void 0) {
         return this.compareVersion(browsers[matchingDefinition]);
diff --git a/src/utils.js b/src/utils.js
index 7e36f8f..7105d32 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -231,6 +231,44 @@ export default class Utils {
     return result;
   }
 
+  /**
+   * Array::find polyfill
+   *
+   * @param  {Array} arr
+   * @param  {Function} predicate
+   * @return {Array}
+   */
+  static find(arr, predicate) {
+    let i;
+    let l;
+    for (i = 0, l = arr.length; i < l; i++ ) {
+      const value = arr[i];
+      if (!predicate(value, i)) continue;
+      return value;
+    }
+  }
+
+  /**
+   * Object::assign polyfill
+   *
+   * @param  {Object} obj
+   * @param  {Object} ...objs
+   * @return {Object}
+   */
+  static assign(obj) {
+    let i;
+    let l;
+    let k;
+    for (i = 1, l = arguments.length; i < l; i++) {
+      const assigner = arguments[i];
+      if (!(typeof assigner === "object")) continue;
+      for (k in assigner) {
+        obj[k] = assigner[k]
+      }
+    }
+    return obj;
+  }
+
   /**
    * Get short version/alias for a browser name
    *

From 066f665aacb131502363c12e99184e52f688ea8e Mon Sep 17 00:00:00 2001
From: Oliver Foster <oliver.foster@kineo.com>
Date: Thu, 19 Dec 2019 10:05:29 +0000
Subject: [PATCH 02/12] Changed bad code

---
 src/utils.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/utils.js b/src/utils.js
index 7105d32..f972f15 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -261,7 +261,7 @@ export default class Utils {
     let k;
     for (i = 1, l = arguments.length; i < l; i++) {
       const assigner = arguments[i];
-      if (!(typeof assigner === "object")) continue;
+      if (typeof assigner !== "object") continue;
       for (k in assigner) {
         obj[k] = assigner[k]
       }

From d0dfa37e502981e2fca5c49a6ac2002228121c87 Mon Sep 17 00:00:00 2001
From: Oliver foster <oliver.foster@kineo.com>
Date: Thu, 19 Dec 2019 10:12:52 +0000
Subject: [PATCH 03/12] Added fallback to native functions

---
 src/utils.js | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/utils.js b/src/utils.js
index f972f15..f1d82d7 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -241,6 +241,9 @@ export default class Utils {
   static find(arr, predicate) {
     let i;
     let l;
+    if (Array.prototype.find) {
+      return Array.prototype.find.call(arr, predicate);
+    }
     for (i = 0, l = arr.length; i < l; i++ ) {
       const value = arr[i];
       if (!predicate(value, i)) continue;
@@ -259,6 +262,9 @@ export default class Utils {
     let i;
     let l;
     let k;
+    if (Object.assign) {
+      return Object.assign.apply(Object, arguments);
+    }
     for (i = 1, l = arguments.length; i < l; i++) {
       const assigner = arguments[i];
       if (typeof assigner !== "object") continue;

From 97aa1e1972561b8bf984b449eb6019c5336f56a8 Mon Sep 17 00:00:00 2001
From: Oliver foster <oliver.foster@kineo.com>
Date: Thu, 19 Dec 2019 10:36:51 +0000
Subject: [PATCH 04/12] Fix travis warnings

---
 src/parser.js | 13 ++++++++-----
 src/utils.js  | 23 +++++++++++++----------
 2 files changed, 21 insertions(+), 15 deletions(-)

diff --git a/src/parser.js b/src/parser.js
index 9f90f0a..831b5cf 100644
--- a/src/parser.js
+++ b/src/parser.js
@@ -82,7 +82,7 @@ class Parser {
   parseBrowser() {
     this.parsedResult.browser = {};
 
-    const browserDescriptor = Utils.find(browserParsersList, _browser => {
+    const browserDescriptor = Utils.find(browserParsersList, (_browser) => {
       if (typeof _browser.test === 'function') {
         return _browser.test(this);
       }
@@ -165,7 +165,7 @@ class Parser {
   parseOS() {
     this.parsedResult.os = {};
 
-    const os = Utils.find(osParsersList, _os => {
+    const os = Utils.find(osParsersList, (_os) => {
       if (typeof _os.test === 'function') {
         return _os.test(this);
       }
@@ -241,7 +241,7 @@ class Parser {
   parsePlatform() {
     this.parsedResult.platform = {};
 
-    const platform = Utils.find(platformParsersList, _platform => {
+    const platform = Utils.find(platformParsersList, (_platform) => {
       if (typeof _platform.test === 'function') {
         return _platform.test(this);
       }
@@ -292,7 +292,7 @@ class Parser {
   parseEngine() {
     this.parsedResult.engine = {};
 
-    const engine = Utils.find(enginesParsersList, _engine => {
+    const engine = Utils.find(enginesParsersList, (_engine) => {
       if (typeof _engine.test === 'function') {
         return _engine.test(this);
       }
@@ -380,7 +380,10 @@ class Parser {
         }
       }
 
-      const platformMatchingDefinition = Utils.find(platformsAndOSNames, name => (this.isPlatform(name)));
+      const platformMatchingDefinition = Utils.find(
+          platformsAndOSNames,
+          name => (this.isPlatform(name))
+        );
       if (platformMatchingDefinition) {
         const platformResult = this.satisfies(platformsAndOSes[platformMatchingDefinition]);
 
diff --git a/src/utils.js b/src/utils.js
index f1d82d7..cdf76e1 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -244,11 +244,14 @@ export default class Utils {
     if (Array.prototype.find) {
       return Array.prototype.find.call(arr, predicate);
     }
-    for (i = 0, l = arr.length; i < l; i++ ) {
+    for (i = 0, l = arr.length; i < l; i+=1) {
       const value = arr[i];
-      if (!predicate(value, i)) continue;
+      if (!predicate(value, i)) {
+        continue;
+      }
       return value;
     }
+    return undefined;
   }
 
   /**
@@ -258,19 +261,19 @@ export default class Utils {
    * @param  {Object} ...objs
    * @return {Object}
    */
-  static assign(obj) {
+  static assign(obj, ...assigners) {
     let i;
     let l;
-    let k;
     if (Object.assign) {
-      return Object.assign.apply(Object, arguments);
+      return Object.assign(obj, ...assigners);
     }
-    for (i = 1, l = arguments.length; i < l; i++) {
-      const assigner = arguments[i];
-      if (typeof assigner !== "object") continue;
-      for (k in assigner) {
-        obj[k] = assigner[k]
+    for (i = 0, l = assigners.length; i < l; i+=1) {
+      const assigner = assigners[i];
+      if (typeof assigner !== 'object') {
+        continue;
       }
+      const keys = Object.keys(assigner);
+      keys.forEach(key => obj[key] = assigner[key]);
     }
     return obj;
   }

From e55055534f95311651ac7ada7b5cfb77f9f1d93d Mon Sep 17 00:00:00 2001
From: Oliver foster <oliver.foster@kineo.com>
Date: Thu, 19 Dec 2019 10:45:33 +0000
Subject: [PATCH 05/12] Fix travis errors

---
 src/parser.js |  5 ++---
 src/utils.js  | 21 ++++++++++++---------
 2 files changed, 14 insertions(+), 12 deletions(-)

diff --git a/src/parser.js b/src/parser.js
index 831b5cf..8bacf3e 100644
--- a/src/parser.js
+++ b/src/parser.js
@@ -381,9 +381,8 @@ class Parser {
       }
 
       const platformMatchingDefinition = Utils.find(
-          platformsAndOSNames,
-          name => (this.isPlatform(name))
-        );
+        platformsAndOSNames,
+        name => (this.isPlatform(name)));
       if (platformMatchingDefinition) {
         const platformResult = this.satisfies(platformsAndOSes[platformMatchingDefinition]);
 
diff --git a/src/utils.js b/src/utils.js
index cdf76e1..6f92bf2 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -210,6 +210,8 @@ export default class Utils {
         return -1;
       }
     }
+
+    return undefined;
   }
 
   /**
@@ -244,12 +246,11 @@ export default class Utils {
     if (Array.prototype.find) {
       return Array.prototype.find.call(arr, predicate);
     }
-    for (i = 0, l = arr.length; i < l; i+=1) {
+    for (i = 0, l = arr.length; i < l; i += 1) {
       const value = arr[i];
-      if (!predicate(value, i)) {
-        continue;
+      if (predicate(value, i)) {
+        return value;
       }
-      return value;
     }
     return undefined;
   }
@@ -262,18 +263,20 @@ export default class Utils {
    * @return {Object}
    */
   static assign(obj, ...assigners) {
+    const result = obj;
     let i;
     let l;
     if (Object.assign) {
       return Object.assign(obj, ...assigners);
     }
-    for (i = 0, l = assigners.length; i < l; i+=1) {
+    for (i = 0, l = assigners.length; i < l; i += 1) {
       const assigner = assigners[i];
-      if (typeof assigner !== 'object') {
-        continue;
+      if (typeof assigner === 'object') {
+        const keys = Object.keys(assigner);
+        keys.forEach((key) => {
+          result[key] = assigner[key];
+        });
       }
-      const keys = Object.keys(assigner);
-      keys.forEach(key => obj[key] = assigner[key]);
     }
     return obj;
   }

From a54868776d7039dddda3468a995e2cba7c409d72 Mon Sep 17 00:00:00 2001
From: Oliver foster <oliver.foster@kineo.com>
Date: Thu, 19 Dec 2019 10:51:30 +0000
Subject: [PATCH 06/12] Fixed linting issues

---
 src/parser.js | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/parser.js b/src/parser.js
index 8bacf3e..2fcfcab 100644
--- a/src/parser.js
+++ b/src/parser.js
@@ -382,7 +382,8 @@ class Parser {
 
       const platformMatchingDefinition = Utils.find(
         platformsAndOSNames,
-        name => (this.isPlatform(name)));
+        name => (this.isPlatform(name)),
+      );
       if (platformMatchingDefinition) {
         const platformResult = this.satisfies(platformsAndOSes[platformMatchingDefinition]);
 

From 3cdfd7de02b16bb4c6f6821ea679f692c76d832b Mon Sep 17 00:00:00 2001
From: Oliver foster <oliver.foster@kineo.com>
Date: Thu, 19 Dec 2019 11:22:40 +0000
Subject: [PATCH 07/12] Expanded test coverage for utils.js

---
 src/utils.js       |  4 ++--
 test/unit/utils.js | 48 +++++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 49 insertions(+), 3 deletions(-)

diff --git a/src/utils.js b/src/utils.js
index 6f92bf2..d771ed2 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -303,7 +303,7 @@ export default class Utils {
    * @param  {string} browserName
    * @return {string}
    */
-  static getBrowserTypeByAlias(browserAlia) {
-    return BROWSER_MAP[browserAlia] || '';
+  static getBrowserTypeByAlias(browserAlias) {
+    return BROWSER_MAP[browserAlias] || '';
   }
 }
diff --git a/test/unit/utils.js b/test/unit/utils.js
index b41843e..0ddd00d 100644
--- a/test/unit/utils.js
+++ b/test/unit/utils.js
@@ -1,11 +1,18 @@
 import test from 'ava';
 import {
-  getBrowserAlias,
   getFirstMatch,
+  getSecondMatch,
+  matchAndReturnConst,
   getWindowsVersionName,
   getMacOSVersionName,
   getAndroidVersionName,
+  getVersionPrecision,
   compareVersions,
+  map,
+  find,
+  assign,
+  getBrowserAlias,
+  getBrowserTypeByAlias
 } from '../../src/utils';
 
 test('getFirstMatch', (t) => {
@@ -13,6 +20,16 @@ test('getFirstMatch', (t) => {
   t.is(matchedVersion, '11.11.11');
 });
 
+test('getSecondMatch', (t) => {
+  const matchedVersion = getSecondMatch(/version\/(\S+)/i, 'Chrome Version/11.11.11 Chrome Version/22.22.22');
+  t.is(matchedVersion, '22.22.22');
+});
+
+test('matchAndReturnConst', (t) => {
+  const _const = matchAndReturnConst(/version/i, 'version', "_const");
+  t.is(_const, '_const');
+});
+
 test('getWindowsVersionName', (t) => {
   t.is(getWindowsVersionName('NT 5.0'), '2000');
   t.is(getWindowsVersionName('XXX'), void 0);
@@ -32,6 +49,11 @@ test('getAndroidVersionName', (t) => {
   t.is(getAndroidVersionName('XXX'), void 0);
 });
 
+test('getVersionPrecision', (t) => {
+  const precision = getVersionPrecision("10.14.5");
+  t.is(precision, 3);
+});
+
 test('compareVersions', (t) => {
   const comparisionsTasks = [
     ['9.0', '10', -1],
@@ -68,7 +90,31 @@ test('compareVersions', (t) => {
   });
 });
 
+test('map', (t) => {
+  const result = map([1,2], (value) => value+2);
+  t.is(result[0], 3);
+  t.is(result[1], 4);
+});
+
+test('find', (t) => {
+  const result = find([1,2], (value) => value==2);
+  t.is(result, 1);
+});
+
+test('assign', (t) => {
+  const result = assign({}, { a: 1 }, { b: 1 }, { b: 2, c: 3 });
+  t.is(result['a'], 1);
+  t.is(result['b'], 2);
+  t.is(result['c'], 3);
+});
+
 test('getBrowserAlias', (t) => {
   t.is(getBrowserAlias('Microsoft Edge'), 'edge');
   t.is(getBrowserAlias('Unexisting Browser'), void 0);
 });
+
+test('getBrowserTypeByAlias', (t) => {
+  t.is(getBrowserTypeByAlias('edge'), 'Microsoft Edge');
+  t.is(getBrowserTypeByAlias(void 0), '');
+});
+

From 64bbd2a9b19840687fd8caa984c964c37b9b929f Mon Sep 17 00:00:00 2001
From: Oliver foster <oliver.foster@kineo.com>
Date: Thu, 19 Dec 2019 11:26:52 +0000
Subject: [PATCH 08/12] Fixed tests

---
 test/unit/utils.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/unit/utils.js b/test/unit/utils.js
index 0ddd00d..1dd39fd 100644
--- a/test/unit/utils.js
+++ b/test/unit/utils.js
@@ -21,7 +21,7 @@ test('getFirstMatch', (t) => {
 });
 
 test('getSecondMatch', (t) => {
-  const matchedVersion = getSecondMatch(/version\/(\S+)/i, 'Chrome Version/11.11.11 Chrome Version/22.22.22');
+  const matchedVersion = getSecondMatch(/version\/(\S+)/ig, 'Chrome Version/11.11.11 Chrome Version/22.22.22');
   t.is(matchedVersion, '22.22.22');
 });
 
@@ -98,7 +98,7 @@ test('map', (t) => {
 
 test('find', (t) => {
   const result = find([1,2], (value) => value==2);
-  t.is(result, 1);
+  t.is(result, 2);
 });
 
 test('assign', (t) => {

From cad365b53e3bc9172898b4f33a67cc438dca1180 Mon Sep 17 00:00:00 2001
From: Oliver foster <oliver.foster@kineo.com>
Date: Thu, 19 Dec 2019 11:38:49 +0000
Subject: [PATCH 09/12] Fixed getSecondMatch test

---
 test/unit/utils.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/unit/utils.js b/test/unit/utils.js
index 1dd39fd..ecaec44 100644
--- a/test/unit/utils.js
+++ b/test/unit/utils.js
@@ -21,7 +21,7 @@ test('getFirstMatch', (t) => {
 });
 
 test('getSecondMatch', (t) => {
-  const matchedVersion = getSecondMatch(/version\/(\S+)/ig, 'Chrome Version/11.11.11 Chrome Version/22.22.22');
+  const matchedVersion = getSecondMatch(/version\/(\S+).*version\/(\S+)/i, 'Chrome Version/11.11.11 Chrome Version/22.22.22');
   t.is(matchedVersion, '22.22.22');
 });
 

From b74bb0caa26b8532ce1b59a044527b6f4aa80760 Mon Sep 17 00:00:00 2001
From: Oliver foster <oliver.foster@kineo.com>
Date: Thu, 19 Dec 2019 11:46:15 +0000
Subject: [PATCH 10/12] Added polyfill tests

---
 test/unit/utils.js | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/test/unit/utils.js b/test/unit/utils.js
index ecaec44..70b365e 100644
--- a/test/unit/utils.js
+++ b/test/unit/utils.js
@@ -94,11 +94,22 @@ test('map', (t) => {
   const result = map([1,2], (value) => value+2);
   t.is(result[0], 3);
   t.is(result[1], 4);
+  const original = Array.prototype.map;
+  delete Array.prototype.map;
+  const polyfillResult = map([1,2], (value) => value+2);
+  Array.prototype.map = original;
+  t.is(polyfillResult[0], 3);
+  t.is(polyfillResult[1], 4);
 });
 
 test('find', (t) => {
   const result = find([1,2], (value) => value==2);
   t.is(result, 2);
+  const original = Array.prototype.find;
+  delete Array.prototype.find;
+  const polyfillResult = find([1,2], (value) => value==2);
+  Array.prototype.find = original;
+  t.is(polyfillResult, 2);
 });
 
 test('assign', (t) => {
@@ -106,6 +117,13 @@ test('assign', (t) => {
   t.is(result['a'], 1);
   t.is(result['b'], 2);
   t.is(result['c'], 3);
+  const original = Object.assign;
+  delete Object.assign;
+  const polyfillResult = assign({}, { a: 1 }, { b: 1 }, { b: 2, c: 3 });
+  Object.assign = original;
+  t.is(polyfillResult['a'], 1);
+  t.is(polyfillResult['b'], 2);
+  t.is(polyfillResult['c'], 3);
 });
 
 test('getBrowserAlias', (t) => {

From f27c7e0580032c170122b0c49e7e03fe75df6b5a Mon Sep 17 00:00:00 2001
From: Oliver foster <oliver.foster@kineo.com>
Date: Thu, 19 Dec 2019 11:49:50 +0000
Subject: [PATCH 11/12] Edited typo

---
 src/utils.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/utils.js b/src/utils.js
index d771ed2..afb51fb 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -300,7 +300,7 @@ export default class Utils {
    * @example
    *   getBrowserAlias('edge') // Microsoft Edge
    *
-   * @param  {string} browserName
+   * @param  {string} browserAlias
    * @return {string}
    */
   static getBrowserTypeByAlias(browserAlias) {

From 5a6af193d24f49e0841f8b4a3c5dedd638628e95 Mon Sep 17 00:00:00 2001
From: Oliver foster <oliver.foster@kineo.com>
Date: Thu, 19 Dec 2019 12:00:46 +0000
Subject: [PATCH 12/12] Extended test cases and fixed bug

---
 src/utils.js       | 2 +-
 test/unit/utils.js | 8 +++++---
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/src/utils.js b/src/utils.js
index afb51fb..d1174bf 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -271,7 +271,7 @@ export default class Utils {
     }
     for (i = 0, l = assigners.length; i < l; i += 1) {
       const assigner = assigners[i];
-      if (typeof assigner === 'object') {
+      if (typeof assigner === 'object' && assigner !== null) {
         const keys = Object.keys(assigner);
         keys.forEach((key) => {
           result[key] = assigner[key];
diff --git a/test/unit/utils.js b/test/unit/utils.js
index 70b365e..1c2a9d5 100644
--- a/test/unit/utils.js
+++ b/test/unit/utils.js
@@ -107,9 +107,11 @@ test('find', (t) => {
   t.is(result, 2);
   const original = Array.prototype.find;
   delete Array.prototype.find;
-  const polyfillResult = find([1,2], (value) => value==2);
+  const polyfillResultFound = find([1,2], (value) => value==2);
+  const polyfillResultNotFound = find([1,2], (value) => value==3);
   Array.prototype.find = original;
-  t.is(polyfillResult, 2);
+  t.is(polyfillResultFound, 2);
+  t.is(polyfillResultNotFound, undefined);
 });
 
 test('assign', (t) => {
@@ -119,7 +121,7 @@ test('assign', (t) => {
   t.is(result['c'], 3);
   const original = Object.assign;
   delete Object.assign;
-  const polyfillResult = assign({}, { a: 1 }, { b: 1 }, { b: 2, c: 3 });
+  const polyfillResult = assign({}, { a: 1 }, { b: 1 }, null, { b: 2, c: 3 });
   Object.assign = original;
   t.is(polyfillResult['a'], 1);
   t.is(polyfillResult['b'], 2);