Rewrite a few helpers to be more efficient

Resolve at definition time if a browser built-in method or our polyfill should be used, so avoid checking it for each call. Also, `helpers.extend` doesn't need to iterate two times on the function arguments. Finally, remove helpers never referenced.

diff --git a/src/core/core.helpers.js b/src/core/core.helpers.js
index 5808150f9aed402e8d7b2ef2e8df5cee5fa7a773..6f634fa7c93e5862d56a845b64bd8cac1937d7ca 100644 (file)
--- a/src/core/core.helpers.js
+++ b/src/core/core.helpers.js
@@ -45,16 +45,10 @@ module.exports = function(Chart) {
                return objClone;
        };
        helpers.extend = function(base) {
-               var len = arguments.length;
-               var additionalArgs = [];
-               for (var i = 1; i < len; i++) {
-                       additionalArgs.push(arguments[i]);
+               var setFn = function(value, key) { base[key] = value; };
+               for (var i = 1, ilen = arguments.length; i < ilen; i++) {
+                       helpers.each(arguments[i], setFn);
                }
-               helpers.each(additionalArgs, function(extensionObject) {
-                       helpers.each(extensionObject, function(value, key) {
-                               base[key] = value;
-                       });
-               });
                return base;
        };
        // Need a special merge function to chart configs since they are now grouped
@@ -102,24 +96,6 @@ module.exports = function(Chart) {
 
                return base;
        };
-       helpers.extendDeep = function(_base) {
-               return _extendDeep.apply(this, arguments);
-
-               function _extendDeep(dst) {
-                       helpers.each(arguments, function(obj) {
-                               if (obj !== dst) {
-                                       helpers.each(obj, function(value, key) {
-                                               if (dst[key] && dst[key].constructor && dst[key].constructor === Object) {
-                                                       _extendDeep(dst[key], value);
-                                               } else {
-                                                       dst[key] = value;
-                                               }
-                                       });
-                               }
-                       });
-                       return dst;
-               }
-       };
        helpers.scaleMerge = function(_base, extension) {
                var base = helpers.clone(_base);
 
@@ -173,17 +149,16 @@ module.exports = function(Chart) {
        helpers.getValueOrDefault = function(value, defaultValue) {
                return value === undefined ? defaultValue : value;
        };
-       helpers.indexOf = function(arrayToSearch, item) {
-               if (Array.prototype.indexOf) {
-                       return arrayToSearch.indexOf(item);
-               } else {
-                       for (var i = 0; i < arrayToSearch.length; i++) {
-                               if (arrayToSearch[i] === item)
+       helpers.indexOf = Array.prototype.indexOf?
+               function(array, item) { return array.indexOf(item); } :
+               function(array, item) {
+                       for (var i = 0, ilen = array.length; i < ilen; ++i) {
+                               if (array[i] === item) {
                                        return i;
+                               }
                        }
                        return -1;
-               }
-       };
+               };
        helpers.where = function(collection, filterCallback) {
                if (helpers.isArray(collection) && Array.prototype.filter) {
                        return collection.filter(filterCallback);
@@ -199,23 +174,17 @@ module.exports = function(Chart) {
                        return filtered;
                }
        };
-       helpers.findIndex = function(arrayToSearch, callback, thisArg) {
-               var index = -1;
-               if (Array.prototype.findIndex) {
-                       index = arrayToSearch.findIndex(callback, thisArg);
-               } else {
-                       for (var i = 0; i < arrayToSearch.length; ++i) {
-                               thisArg = thisArg !== undefined ? thisArg : arrayToSearch;
-
-                               if (callback.call(thisArg, arrayToSearch[i], i, arrayToSearch)) {
-                                       index = i;
-                                       break;
+       helpers.findIndex = Array.prototype.findIndex?
+               function(array, callback, scope) { return array.findIndex(callback, scope); } :
+               function(array, callback, scope) {
+                       scope = scope === undefined? array : scope;
+                       for (var i = 0, ilen = array.length; i < ilen; ++i) {
+                               if (callback.call(scope, array[i], i, array)) {
+                                       return i;
                                }
                        }
-               }
-
-               return index;
-       };
+                       return -1;
+               };
        helpers.findNextWhere = function(arrayToSearch, filterCallback, startIndex) {
                // Default to start of the array
                if (startIndex === undefined || startIndex === null) {
@@ -270,12 +239,6 @@ module.exports = function(Chart) {
                        return id++;
                };
        })();
-       helpers.warn = function(str) {
-               //Method for warning of errors
-               if (console && typeof console.warn === "function") {
-                       console.warn(str);
-               }
-       };
        //-- Math methods
        helpers.isNumber = function(n) {
                return !isNaN(parseFloat(n)) && isFinite(n);
@@ -301,24 +264,20 @@ module.exports = function(Chart) {
                        }
                }, Number.POSITIVE_INFINITY);
        };
-       helpers.sign = function(x) {
-               if (Math.sign) {
-                       return Math.sign(x);
-               } else {
+       helpers.sign = Math.sign?
+               function(x) { return Math.sign(x); } :
+               function(x) {
                        x = +x; // convert to a number
                        if (x === 0 || isNaN(x)) {
                                return x;
                        }
                        return x > 0 ? 1 : -1;
-               }
-       };
-       helpers.log10 = function(x) {
-               if (Math.log10) {
-                       return Math.log10(x);
-               } else {
+               };
+       helpers.log10 = Math.log10?
+               function(x) { return Math.log10(x); } :
+               function(x) {
                        return Math.log(x) / Math.LN10;
-               }
-       };
+               };
        helpers.toRadians = function(degrees) {
                return degrees * (Math.PI / 180);
        };
@@ -945,12 +904,11 @@ module.exports = function(Chart) {
                        hiddenIframe.parentNode.removeChild(hiddenIframe);
                }
        };
-       helpers.isArray = function(obj) {
-               if (!Array.isArray) {
+       helpers.isArray = Array.isArray?
+               function(obj) { return Array.isArray(obj); } :
+               function(obj) {
                        return Object.prototype.toString.call(obj) === '[object Array]';
-               }
-               return Array.isArray(obj);
-       };
+               };
        //! @see http://stackoverflow.com/a/14853974
        helpers.arrayEquals = function(a0, a1) {
                var i, ilen, v0, v1;