feat: re-implemented basic feature as a set operation

BREAKING CHANGE: export structure updated

index.js

@@ -1 +1 @@
-module.exports = require('./src/update');
+module.exports = require('./src');

src/index.js

@@ -0,0 +1,5 @@
+const set = require('./set');
+
+module.exports = {
+    set
+};

src/set/index.js

@@ -0,0 +1,56 @@
+module.exports = set;
+
+function set(object, path, value) {
+    const pathArray = Array.isArray(path)
+        ? path
+        : path.split('.');
+
+    return doSet(object, pathArray, 0, value);
+}
+
+function doSet(object, path, index, value) {
+    if (index === path.length) {
+        return value;
+    }
+
+    const key = path[index];
+
+    if (!key) {
+        return doSet(object, path, index + 1, value);
+    }
+
+    const source = object || createSource(key);
+    const item = source[key];
+    const newItem = doSet(item, path, index + 1, value);
+
+    if (item === newItem) {
+        return source;
+    }
+
+    if (!Array.isArray(source)) {
+        return Object.assign({}, source, {
+            [key]: newItem
+        });
+    }
+
+    if (isNumber(key)) {
+        return source
+            .slice(0, key)
+            .concat(
+                [ newItem ],
+                source.slice(key + 1)
+            );
+    }
+
+    return Object.assign(source.slice(), {
+        [key]: newItem
+    });
+}
+
+function createSource(key) {
+    return isNumber(key) ? [] : {};
+}
+
+function isNumber(value) {
+    return value.toString() === parseInt(value, 0).toString();
+}

tests/update.spec.js → tests/set.spec.js

@@ -1,6 +1,6 @@
-const update = require('../src/update');
+const set = require('../src/set');
 
-describe('update', () => {
+describe('set', () => {
     const source = {
         a: {
             a1: 1,
@@ -17,15 +17,15 @@ describe('update', () => {
         it('should update value', () => {
             const newValue = 6;
 
-            const result = update(source, [ 'b', 'b1' ], newValue);
+            const result = set(source, [ 'b', 'b1' ], newValue);
 
             expect(result.b.b1).to.be.equal(newValue);
         });
 
         it('should update value not considering dots as delimiter', () => {
             const newValue = 6;
 
-            const result = update(source, [ 'b.b1' ], newValue);
+            const result = set(source, [ 'b.b1' ], newValue);
 
             expect(result['b.b1']).to.be.equal(newValue);
         });
@@ -36,7 +36,7 @@ describe('update', () => {
 
         let result;
         beforeEach(() => {
-            result = update(source, 'b.b1', newValue);
+            result = set(source, 'b.b1', newValue);
         });
 
         it('should update value considering dots as delimiter', () => {
@@ -62,23 +62,23 @@ describe('update', () => {
     it('should ignore empty path items', () => {
         const newValue = 6;
 
-        const result = update(source, 'b..b1', newValue);
+        const result = set(source, 'b..b1', newValue);
 
         expect(result.b.b1).to.be.equal(newValue);
     });
 
     it('should create intermediate items if not exists', () => {
         const newValue = 6;
 
-        const result = update(source, 'c.c1', newValue);
+        const result = set(source, 'c.c1', newValue);
 
         expect(result.c.c1).to.be.equal(newValue);
     });
 
     it('should create arrays item if not exists and addressed by index', () => {
         const newValue = 6;
 
-        const result = update(source, 'c.0', newValue);
+        const result = set(source, 'c.0', newValue);
 
         expect(result.c).to.be.an('array');
         expect(result.c[0]).to.be.equal(newValue);