partition_object_method

helpful.js

@@ -9,6 +9,26 @@
 }(typeof self !== 'undefined' ? self : this, function() {
 	const helpful = {};
 
+
+       // partitionObject #30
+
+    helpful.partitionObject = function(obj, predicate) {
+			return Object.entries(obj).reduce(
+				([pass, fail], [key, value]) => {
+				if (predicate(key, value)) {
+					pass[key] = value;
+				} else {
+					fail[key] = value;
+				}
+				return [pass, fail];
+				},
+				[{}, {}] 
+			);
+  };   
+
+
+
+
 	helpful.stringToArray = function(string) {
 		if(string == null) {
 			return "";

test/tester.js

@@ -3,8 +3,39 @@ const assert = require("assert");
 
 describe("Tests", function() {
 	describe("General", function() {
+
 		let i = 0;
 
+
+				i++;
+		it(`${i}: partitionObject - Should partition object by value > 2`, function () {
+			let expected = [{ c: 3, d: 4 }, { a: 1, b: 2 }];
+			let actual = helpful.partitionObject({ a: 1, b: 2, c: 3, d: 4 }, (k, v) => v > 2);
+			assert.deepEqual(actual, expected);
+		});
+
+		i++;
+		it(`${i}: partitionObject - Should partition object by key === 'a'`, function () {
+			let expected = [{ a: 1 }, { b: 2, c: 3, d: 4 }];
+			let actual = helpful.partitionObject({ a: 1, b: 2, c: 3, d: 4 }, (k, v) => k === "a");
+			assert.deepEqual(actual, expected);
+		});
+
+		i++;
+		it(`${i}: partitionObject - Should return all in first if predicate always true`, function () {
+			let expected = [{ a: 1, b: 2 }, {}];
+			let actual = helpful.partitionObject({ a: 1, b: 2 }, () => true);
+			assert.deepEqual(actual, expected);
+		});
+
+		i++;
+		it(`${i}: partitionObject - Should return all in second if predicate always false`, function () {
+			let expected = [{}, { a: 1, b: 2 }];
+			let actual = helpful.partitionObject({ a: 1, b: 2 }, () => false);
+			assert.deepEqual(actual, expected);
+		});
+
+
 		i++;
 		it(`${i}: stringToArray - should convert string to array`, function() {
 			let expected = ["t", "e", "s", "t"];