|  | var test = require("tape") | 
|  | var extend = require("./") | 
|  | var mutableExtend = require("./mutable") | 
|  |  | 
|  | test("merge", function(assert) { | 
|  | var a = { a: "foo" } | 
|  | var b = { b: "bar" } | 
|  |  | 
|  | assert.deepEqual(extend(a, b), { a: "foo", b: "bar" }) | 
|  | assert.end() | 
|  | }) | 
|  |  | 
|  | test("replace", function(assert) { | 
|  | var a = { a: "foo" } | 
|  | var b = { a: "bar" } | 
|  |  | 
|  | assert.deepEqual(extend(a, b), { a: "bar" }) | 
|  | assert.end() | 
|  | }) | 
|  |  | 
|  | test("undefined", function(assert) { | 
|  | var a = { a: undefined } | 
|  | var b = { b: "foo" } | 
|  |  | 
|  | assert.deepEqual(extend(a, b), { a: undefined, b: "foo" }) | 
|  | assert.deepEqual(extend(b, a), { a: undefined, b: "foo" }) | 
|  | assert.end() | 
|  | }) | 
|  |  | 
|  | test("handle 0", function(assert) { | 
|  | var a = { a: "default" } | 
|  | var b = { a: 0 } | 
|  |  | 
|  | assert.deepEqual(extend(a, b), { a: 0 }) | 
|  | assert.deepEqual(extend(b, a), { a: "default" }) | 
|  | assert.end() | 
|  | }) | 
|  |  | 
|  | test("is immutable", function (assert) { | 
|  | var record = {} | 
|  |  | 
|  | extend(record, { foo: "bar" }) | 
|  | assert.equal(record.foo, undefined) | 
|  | assert.end() | 
|  | }) | 
|  |  | 
|  | test("null as argument", function (assert) { | 
|  | var a = { foo: "bar" } | 
|  | var b = null | 
|  | var c = void 0 | 
|  |  | 
|  | assert.deepEqual(extend(b, a, c), { foo: "bar" }) | 
|  | assert.end() | 
|  | }) | 
|  |  | 
|  | test("mutable", function (assert) { | 
|  | var a = { foo: "bar" } | 
|  |  | 
|  | mutableExtend(a, { bar: "baz" }) | 
|  |  | 
|  | assert.equal(a.bar, "baz") | 
|  | assert.end() | 
|  | }) | 
|  |  | 
|  | test("null prototype", function(assert) { | 
|  | var a = { a: "foo" } | 
|  | var b = Object.create(null) | 
|  | b.b = "bar"; | 
|  |  | 
|  | assert.deepEqual(extend(a, b), { a: "foo", b: "bar" }) | 
|  | assert.end() | 
|  | }) | 
|  |  | 
|  | test("null prototype mutable", function (assert) { | 
|  | var a = { foo: "bar" } | 
|  | var b = Object.create(null) | 
|  | b.bar = "baz"; | 
|  |  | 
|  | mutableExtend(a, b) | 
|  |  | 
|  | assert.equal(a.bar, "baz") | 
|  | assert.end() | 
|  | }) | 
|  |  | 
|  | test("prototype pollution", function (assert) { | 
|  | var a = {} | 
|  | var maliciousPayload = '{"__proto__":{"oops":"It works!"}}' | 
|  |  | 
|  | assert.strictEqual(a.oops, undefined) | 
|  | extend({}, maliciousPayload) | 
|  | assert.strictEqual(a.oops, undefined) | 
|  | assert.end() | 
|  | }) | 
|  |  | 
|  | test("prototype pollution mutable", function (assert) { | 
|  | var a = {} | 
|  | var maliciousPayload = '{"__proto__":{"oops":"It works!"}}' | 
|  |  | 
|  | assert.strictEqual(a.oops, undefined) | 
|  | mutableExtend({}, maliciousPayload) | 
|  | assert.strictEqual(a.oops, undefined) | 
|  | assert.end() | 
|  | }) |