var test = require('../util/test')(__filename);

var merge = require('../../packages/object-merge');

test('shallow merge merges properties', function(t) {

t.plan(2);

var src = {a: 3, b: 5};

t.deepEqual(merge(src, {a: 4, c: 8}), {a: 4, b: 5, c: 8});

t.deepEqual(src, {a: 4, b: 5, c: 8});

t.end();

});

test('shallow merge merges into new object', function(t) {

t.plan(2);

var src = {};

t.deepEqual(merge(src, {a: 3, b: 5}, {a: 4, c: 8}), {a: 4, b: 5, c: 8});

t.deepEqual(src, {a: 4, b: 5, c: 8});

t.end();

});

test('shallow merge does not clone child objects', function(t) {

t.plan(5);

var obj = {p: 4};

var src2 = {a: 3, b: 5};

t.deepEqual(merge(src2, {c: obj}), {a: 3, b: 5, c: {p: 4}});

obj.p = 9;

t.deepEqual(src2, {a: 3, b: 5, c: {p: 9}});

var arrInner = [1, 2, 3];

var arrOuter = ['a', 'b', arrInner];

var src1 = {a: 3, b: 5};

t.deepEqual(merge(src1, {c: arrOuter}), {a: 3, b: 5, c: ['a', 'b', [1, 2, 3]]});

t.equal(arrOuter, src1.c);

t.equal(arrInner, src1.c[2]);

});

test('null values are copied', function(t) {

t.plan(2);

var src = {a: 3, b: 5};

t.deepEqual(merge(src, {a: null, c: null}), {a: null, b: 5, c: null});

t.deepEqual(src, {a: null, b: 5, c: null});

t.end();

});

test('explicitly undefined values are copied', function(t) {

t.plan(2);

var src = {a: 3, b: 5};

t.deepEqual(merge(src, {a: undefined, c: undefined}), {a: undefined, b: 5, c: undefined});

t.deepEqual(src, {a: undefined, b: 5, c: undefined});

t.end();

});

test('when no extendee, extenders is returned unmutated', function(t) {

t.plan(3);

var src = {a: 3, b: 5};

var srcRef = src;

t.deepEqual(src, merge(src));

t.equal(srcRef, src);

t.equal(srcRef, src);

t.end();

});

test('extendee and extenders can be functions', function(t) {

t.plan(2);

var fn = function() {};

var result = merge(fn, {a: 4});

t.ok(typeof result == 'function');

t.ok(result.a === 4);

t.end();

});

test('extendee and extenders must be objects', function(t) {

t.plan(4);

t.throws(function() {

merge(3, {a: 4, b: 5});

});

t.throws(function() {

merge({a: 4, b: 5}, 3);

});

t.throws(function() {

merge({a: 4, b: 5}, true);

});

t.throws(function() {

merge({a: 4, b: 5}, {b: 4, c: 5}, 'c');

});

t.end();

});