fix: Create a simple merge object utility (#849)

src/utils.ts

@@ -223,6 +223,10 @@ const isStringOrNumber = (value: any): boolean =>
 const isEmpty = (value: Dictionary<any> | null | undefined): boolean =>
     value == null || !(Object.keys(value) || value).length;
 
+const mergeObjects = <T extends object>(...objects: T[]): T => {
+    return Object.assign({}, ...objects);
+};
+
 export {
     createCookieString,
     revertCookieString,
@@ -251,4 +255,5 @@ export {
     isDataPlanSlug,
     isEmpty,
     isValidCustomFlagProperty,
+    mergeObjects,
 };

test/src/tests-utils.ts

@@ -12,6 +12,7 @@ import {
     isObject,
     isStringOrNumber,
     isValidCustomFlagProperty,
+    mergeObjects,
     parseNumber,
     parseStringOrNumber,
     replaceApostrophesWithQuotes,
@@ -373,4 +374,50 @@ describe('Utils', () => {
             expect(isValidCustomFlagProperty(undefined), 'undefined').to.equal(false);
         });
     });
+
+    describe('#mergeObjects', () => {
+        it('should merge objects', () => {
+            const obj1 = { foo: 'bar' };
+            const obj2 = { fizz: 'buzz' };
+
+            expect(mergeObjects<any>(obj1, obj2)).to.deep.equal({
+                foo: 'bar',
+                fizz: 'buzz',
+            });
+        });
+
+        it('should override values with the same keys in the order they appear, with the subsequent objects taking priority', () => {
+            const obj1 = { foo: 'bar', flip: 'flop' };
+            const obj2 = { fizz: 'buzz', narf: 'poit' };
+            const obj3 = { foo: 'baz' };
+
+            expect(mergeObjects<any>(obj1, obj2, obj3)).to.deep.equal({
+                foo: 'baz',
+                fizz: 'buzz',
+                flip: 'flop',
+                narf: 'poit',
+            });
+        });
+
+        it('should merge objects with nested objects', () => {
+            const obj1 = { foo: { bar: 'baz' } };
+            const obj2 = { fizz: { buzz: 'fizzbuzz' } };
+
+            expect(mergeObjects<any>(obj1, obj2)).to.deep.equal({
+                foo: { bar: 'baz' },
+                fizz: { buzz: 'fizzbuzz' },
+            });
+        });
+
+        it('should return a copy of the original object', () => {
+            const obj1 = { foo: 'bar' };
+            const obj2 = { fizz: 'buzz' };
+
+            const merged = mergeObjects<any>(obj1, obj2);
+            merged.foo = 'not-bar';
+
+            expect(obj1.foo).to.equal('bar');
+            expect(merged.foo).to.equal('not-bar');
+        });
+    });
 });