fix(SpyConstructor): correctly forward constructor arguments to the o…

…riginal constructor
TNG · Jan 5, 2017 · 198e77d · 198e77d
1 parent ad97a5e
commit 198e77d
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Showing 2 changed files with 7 additions and 1 deletion.
diff --git a/src/constructors.js b/src/constructors.js
@@ -2,7 +2,7 @@ var R = require('ramda')
 var fa = require('fluent-arguments')
 
 function getConstructorInstanceWithArgs (Constructor, constructorArgs) {
-  return new (Function.prototype.bind.apply(Constructor, arguments))()
+  return new (Function.prototype.bind.apply(Constructor, [ null ].concat(Array.prototype.slice.call(constructorArgs))))()
 }
 
 function getArrayFromArrayLikeObject (args) {

diff --git a/test/index.spec.js b/test/index.spec.js
@@ -35,6 +35,7 @@ beforeEach(function () {
   })
 
   TestConstructor = function () {
+    this.args = Array.prototype.slice.call(arguments)
     this.field3 = function () { return 3 }
     this.field4 = sinon.stub()
     Object.defineProperty(this, 'getter', { get: function () { throw new Error('getter was evaluated') } })
@@ -133,6 +134,11 @@ describe('getSpyConstructor', function () {
     expect(spiedObject).to.be.an.instanceof(TestConstructor)
   })
 
+  it('should create instances using the right arguments', function () {
+    var spiedObject = new SpyConstructor('Var 1', 2)
+    expect(spiedObject.args).to.deep.equal([ 'Var 1', 2 ])
+  })
+
   it('should put spies on all methods', function () {
     var spiedObject = new SpyConstructor()