diff --git a/dist/lodash.compat.js b/dist/lodash.compat.js
index 1fedccf5f..5c09677dd 100644
--- a/dist/lodash.compat.js
+++ b/dist/lodash.compat.js
@@ -288,7 +288,12 @@
           typeCache = cache[type] || (cache[type] = {});
 
       if (type == 'object') {
-        (typeCache[key] || (typeCache[key] = [])).push(value);
+        var array = typeCache[key];
+        if (array) {
+          array.push(value);
+        } else {
+          typeCache[key] = [value];
+        }
       } else {
         typeCache[key] = true;
       }
@@ -1850,6 +1855,7 @@
      * @private
      * @param {Object} [options] The compile options object.
      * @param {string} [options.args] A comma separated string of iteration function arguments.
+     * @param {string} [options.init] The string representation of the initial `result` value.
      * @param {string} [options.top] Code to execute before the iteration branches.
      * @param {string} [options.loop] Code to execute in the object loop.
      * @param {boolean} [options.useHas] Specify using `hasOwnProperty` checks in the object loop.
@@ -3633,7 +3639,11 @@
      * // => { '3': ['one', 'two'], '5': ['three'] }
      */
     var groupBy = createAggregator(function(result, value, key) {
-      (hasOwnProperty.call(result, key) ? result[key] : result[key] = []).push(value);
+      if (hasOwnProperty.call(result, key)) {
+        result[key].push(value);
+      } else {
+        result[key] = [value];
+      }
     });
 
     /**
diff --git a/dist/lodash.compat.min.js b/dist/lodash.compat.min.js
index f9ed8e89c..0569bfb3a 100644
--- a/dist/lodash.compat.min.js
+++ b/dist/lodash.compat.min.js
@@ -4,7 +4,7 @@
  * Build: `lodash -o ./dist/lodash.compat.js`
  */
 ;(function(){function n(n,t){if(n!==t){if(n>t||typeof n=="undefined")return 1;if(n<t||typeof t=="undefined")return-1}return 0}function t(n,t,r){r=(r||0)-1;for(var e=n?n.length:0;++r<e;)if(n[r]===t)return r;return-1}function r(n,r){var e=typeof r;if(n=n.h,"boolean"==e||null==r)return n[r]?0:-1;"number"!=e&&"string"!=e&&(e="object");var u="number"==e?r:C+r;return n=(n=n[e])&&n[u],"object"==e?n&&-1<t(n,r)?0:-1:n?0:-1}function e(n){var t=this.h,r=typeof n;if("boolean"==r||null==n)t[n]=true;else{"number"!=r&&"string"!=r&&(r="object");
-var e="number"==r?n:C+n,t=t[r]||(t[r]={});"object"==r?(t[e]||(t[e]=[])).push(n):t[e]=true}}function u(n){return n.charCodeAt(0)}function o(t,r){return n(t.i,r.i)||t.j-r.j}function a(t,r){for(var e=t.i,u=r.i,o=-1,a=e.length;++o<a;){var i=n(e[o],u[o]);if(i)return i}return t.j-r.j}function i(n){var t=-1,r=n.length,u=n[0],o=n[r/2|0],a=n[r-1];if(u&&typeof u=="object"&&o&&typeof o=="object"&&a&&typeof a=="object")return false;for(u=p(),u["false"]=u["null"]=u["true"]=u.undefined=false,o=p(),o.g=n,o.h=u,o.push=e;++t<r;)o.push(n[t]);
+var e="number"==r?n:C+n,t=t[r]||(t[r]={});"object"==r?(r=t[e])?r.push(n):t[e]=[n]:t[e]=true}}function u(n){return n.charCodeAt(0)}function o(t,r){return n(t.i,r.i)||t.j-r.j}function a(t,r){for(var e=t.i,u=r.i,o=-1,a=e.length;++o<a;){var i=n(e[o],u[o]);if(i)return i}return t.j-r.j}function i(n){var t=-1,r=n.length,u=n[0],o=n[r/2|0],a=n[r-1];if(u&&typeof u=="object"&&o&&typeof o=="object"&&a&&typeof a=="object")return false;for(u=p(),u["false"]=u["null"]=u["true"]=u.undefined=false,o=p(),o.g=n,o.h=u,o.push=e;++t<r;)o.push(n[t]);
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 }function b(n){function e(n){return n&&typeof n=="object"&&!ce(n)&&Pr.call(n,"__wrapped__")?n:new w(n)}function w(n,t){this.__chain__=!!t,this.__wrapped__=n}function j(n){function t(){if(e){var n=v(e);Dr.apply(n,arguments)}if(this instanceof t){var o=ut(r.prototype),n=r.apply(o,n||arguments);return Zt(n)?n:o}return r.apply(u,n||arguments)}var r=n[0],e=n[2],u=n[4];return ee(t,n),t}function O(n,t,r,e,u){if(r){var o=r(n);if(typeof o!="undefined")return o}if(!Zt(n))return n;var a=Er.call(n);if(!tt[a]||!re.nodeClass&&s(n))return n;
@@ -34,7 +34,7 @@ var pr=n.Array,sr=n.Boolean,gr=n.Date,hr=n.Function,vr=n.Math,yr=n.Number,mr=n.O
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 for(t in te)Pr.call(te,t)&&!Pr.call(te[t],r)&&(te[t][r]=false)}}(),w.prototype=e.prototype;var re=e.support={};!function(){var t=function(){this.x=1},r={0:1,length:1},e=[];t.prototype={valueOf:1,y:1};for(var u in new t)e.push(u);for(u in arguments);re.argsClass=Er.call(arguments)==V,re.argsObject=arguments.constructor==mr&&!(arguments instanceof pr),re.enumErrorProps=qr.call(jr,"message")||qr.call(jr,"name"),re.enumPrototypes=qr.call(t,"prototype"),re.funcDecomp=!wt(n.WinRTError)&&W.test(b),re.funcNames=typeof hr.name=="string",re.nonEnumArgs=0!=u,re.nonEnumShadows=!/valueOf/.test(e),re.ownLast="x"!=e[0],re.spliceObjects=($r.call(r,0,1),!r[0]),re.unindexedChars="xx"!="x"[0]+mr("x")[0];
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-});var ue=bt({a:"p",b:"[]",e:"",c:"s.push(l)",f:true}),oe=mt(function(n,t,r){Pr.call(n,r)?n[r]++:n[r]=1}),ae=mt(function(n,t,r){(Pr.call(n,r)?n[r]:n[r]=[]).push(t)}),ie=mt(function(n,t,r){n[r]=t}),le=$t,fe=bt({a:"p,b,x",b:"p",e:"b=b&&typeof x=='undefined'?b:a(b,x,3)",c:"if(b(p[l],l,p)===false){return s}",f:false}),ce=Kr||function(n){return n&&typeof n=="object"&&typeof n.length=="number"&&Er.call(n)==U||false};re.dom||(Qt=function(n){return n&&typeof n=="object"&&1===n.nodeType&&!pe(n)||false}),Yt(/x/)&&(Yt=function(n){return typeof n=="function"&&Er.call(n)==J
+});var ue=bt({a:"p",b:"[]",e:"",c:"s.push(l)",f:true}),oe=mt(function(n,t,r){Pr.call(n,r)?n[r]++:n[r]=1}),ae=mt(function(n,t,r){Pr.call(n,r)?n[r].push(t):n[r]=[t]}),ie=mt(function(n,t,r){n[r]=t}),le=$t,fe=bt({a:"p,b,x",b:"p",e:"b=b&&typeof x=='undefined'?b:a(b,x,3)",c:"if(b(p[l],l,p)===false){return s}",f:false}),ce=Kr||function(n){return n&&typeof n=="object"&&typeof n.length=="number"&&Er.call(n)==U||false};re.dom||(Qt=function(n){return n&&typeof n=="object"&&1===n.nodeType&&!pe(n)||false}),Yt(/x/)&&(Yt=function(n){return typeof n=="function"&&Er.call(n)==J
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diff --git a/dist/lodash.js b/dist/lodash.js
index b1253b06a..c255002ad 100644
--- a/dist/lodash.js
+++ b/dist/lodash.js
@@ -278,7 +278,12 @@
           typeCache = cache[type] || (cache[type] = {});
 
       if (type == 'object') {
-        (typeCache[key] || (typeCache[key] = [])).push(value);
+        var array = typeCache[key];
+        if (array) {
+          array.push(value);
+        } else {
+          typeCache[key] = [value];
+        }
       } else {
         typeCache[key] = true;
       }
@@ -3322,7 +3327,11 @@
      * // => { '3': ['one', 'two'], '5': ['three'] }
      */
     var groupBy = createAggregator(function(result, value, key) {
-      (hasOwnProperty.call(result, key) ? result[key] : result[key] = []).push(value);
+      if (hasOwnProperty.call(result, key)) {
+        result[key].push(value);
+      } else {
+        result[key] = [value];
+      }
     });
 
     /**
diff --git a/dist/lodash.min.js b/dist/lodash.min.js
index 27cbd98cd..e648378e6 100644
--- a/dist/lodash.min.js
+++ b/dist/lodash.min.js
@@ -4,7 +4,7 @@
  * Build: `lodash modern -o ./dist/lodash.js`
  */
 ;(function(){function n(n,t){if(n!==t){if(n>t||typeof n=="undefined")return 1;if(n<t||typeof t=="undefined")return-1}return 0}function t(n,t,r){r=(r||0)-1;for(var e=n?n.length:0;++r<e;)if(n[r]===t)return r;return-1}function r(n,r){var e=typeof r;if(n=n.h,"boolean"==e||null==r)return n[r]?0:-1;"number"!=e&&"string"!=e&&(e="object");var u="number"==e?r:k+r;return n=(n=n[e])&&n[u],"object"==e?n&&-1<t(n,r)?0:-1:n?0:-1}function e(n){var t=this.h,r=typeof n;if("boolean"==r||null==n)t[n]=true;else{"number"!=r&&"string"!=r&&(r="object");
-var e="number"==r?n:k+n,t=t[r]||(t[r]={});"object"==r?(t[e]||(t[e]=[])).push(n):t[e]=true}}function u(n){return n.charCodeAt(0)}function o(t,r){return n(t.i,r.i)||t.j-r.j}function i(t,r){for(var e=t.i,u=r.i,o=-1,i=e.length;++o<i;){var a=n(e[o],u[o]);if(a)return a}return t.j-r.j}function a(n){var t=-1,r=n.length,u=n[0],o=n[r/2|0],i=n[r-1];if(u&&typeof u=="object"&&o&&typeof o=="object"&&i&&typeof i=="object")return false;for(u=p(),u["false"]=u["null"]=u["true"]=u.undefined=false,o=p(),o.g=n,o.h=u,o.push=e;++t<r;)o.push(n[t]);
+var e="number"==r?n:k+n,t=t[r]||(t[r]={});"object"==r?(r=t[e])?r.push(n):t[e]=[n]:t[e]=true}}function u(n){return n.charCodeAt(0)}function o(t,r){return n(t.i,r.i)||t.j-r.j}function i(t,r){for(var e=t.i,u=r.i,o=-1,i=e.length;++o<i;){var a=n(e[o],u[o]);if(a)return a}return t.j-r.j}function a(n){var t=-1,r=n.length,u=n[0],o=n[r/2|0],i=n[r-1];if(u&&typeof u=="object"&&o&&typeof o=="object"&&i&&typeof i=="object")return false;for(u=p(),u["false"]=u["null"]=u["true"]=u.undefined=false,o=p(),o.g=n,o.h=u,o.push=e;++t<r;)o.push(n[t]);
 return o}function f(n){return tt[n]}function l(n){return"\\"+ut[n]}function c(){return _.pop()||[]}function p(){return w.pop()||{g:null,h:null,i:null,"false":false,j:0,"null":false,number:null,object:null,push:null,string:null,"true":false,undefined:false,k:null}}function s(n){n.length=0,_.length<C&&_.push(n)}function h(n){var t=n.h;t&&h(t),n.g=n.h=n.i=n.object=n.number=n.string=n.k=null,w.length<C&&w.push(n)}function v(n,t,r){t||(t=0),typeof r=="undefined"&&(r=n?n.length:0);var e=-1;r=r-t||0;for(var u=Array(0>r?0:r);++e<r;)u[e]=n[t+e];
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 t=t&&typeof r=="undefined"?t:it(t,r,3);for(var e in n)if(false===t(n[e],e,n))break;return n}function _(n){var t=[];if(!n||!et[typeof n])return t;for(var r in n)Ar.call(n,r)&&t.push(r);return t}function w(n){return n&&typeof n=="object"&&!ee(n)&&Ar.call(n,"__wrapped__")?n:new C(n)}function C(n,t){this.__chain__=!!t,this.__wrapped__=n}function tt(n){function t(){if(e){var n=v(e);Ir.apply(n,arguments)}if(this instanceof t){var o=ut(r.prototype),n=r.apply(o,n||arguments);return Jt(n)?n:o}return r.apply(u,n||arguments)
@@ -30,7 +30,7 @@ for(t=it(t,r,3);u--&&(r=e[u],false!==t(n[r],r,n)););return n}function Xt(n){var
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diff --git a/dist/lodash.underscore.js b/dist/lodash.underscore.js
index 8fdff05a6..bbe62b208 100644
--- a/dist/lodash.underscore.js
+++ b/dist/lodash.underscore.js
@@ -2269,7 +2269,11 @@
    * // => { '3': ['one', 'two'], '5': ['three'] }
    */
   var groupBy = createAggregator(function(result, value, key) {
-    (hasOwnProperty.call(result, key) ? result[key] : result[key] = []).push(value);
+    if (hasOwnProperty.call(result, key)) {
+      result[key].push(value);
+    } else {
+      result[key] = [value];
+    }
   });
 
   /**
diff --git a/dist/lodash.underscore.min.js b/dist/lodash.underscore.min.js
index 44d553180..0eb5ad82e 100644
--- a/dist/lodash.underscore.min.js
+++ b/dist/lodash.underscore.min.js
@@ -22,7 +22,7 @@ if(e)for(var u in e)"undefined"==typeof n[u]&&(n[u]=e[u])}return n}function U(n,
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diff --git a/lodash.js b/lodash.js
index f77506ffe..e43cb59f7 100644
--- a/lodash.js
+++ b/lodash.js
@@ -287,7 +287,12 @@
           typeCache = cache[type] || (cache[type] = {});
 
       if (type == 'object') {
-        (typeCache[key] || (typeCache[key] = [])).push(value);
+        var array = typeCache[key];
+        if (array) {
+          array.push(value);
+        } else {
+          typeCache[key] = [value];
+        }
       } else {
         typeCache[key] = true;
       }
@@ -3652,7 +3657,11 @@
      * // => { '3': ['one', 'two'], '5': ['three'] }
      */
     var groupBy = createAggregator(function(result, value, key) {
-      (hasOwnProperty.call(result, key) ? result[key] : result[key] = []).push(value);
+      if (hasOwnProperty.call(result, key)) {
+        result[key].push(value);
+      } else {
+        result[key] = [value];
+      }
     });
 
     /**