require new in constructor

src/Canvas.cc

@@ -63,6 +63,10 @@ Canvas::Initialize(Nan::ADDON_REGISTER_FUNCTION_ARGS_TYPE target) {
  */
 
 NAN_METHOD(Canvas::New) {
+  if (!info.IsConstructCall()) {
+    return Nan::ThrowTypeError("Class constructors cannot be invoked without 'new'");
+  }
+
   int width = 0, height = 0;
   canvas_type_t type = CANVAS_TYPE_IMAGE;
   if (info[0]->IsNumber()) width = info[0]->Uint32Value();

src/CanvasGradient.cc

@@ -35,6 +35,10 @@ Gradient::Initialize(Nan::ADDON_REGISTER_FUNCTION_ARGS_TYPE target) {
  */
 
 NAN_METHOD(Gradient::New) {
+  if (!info.IsConstructCall()) {
+    return Nan::ThrowTypeError("Class constructors cannot be invoked without 'new'");
+  }
+
   // Linear
   if (4 == info.Length()) {
     Gradient *grad = new Gradient(

src/CanvasPattern.cc

@@ -37,6 +37,10 @@ Pattern::Initialize(Nan::ADDON_REGISTER_FUNCTION_ARGS_TYPE target) {
  */
 
 NAN_METHOD(Pattern::New) {
+  if (!info.IsConstructCall()) {
+    return Nan::ThrowTypeError("Class constructors cannot be invoked without 'new'");
+  }
+
   int w = 0
     , h = 0;
   cairo_surface_t *surface;

src/CanvasRenderingContext2d.cc

@@ -536,6 +536,10 @@ Context2d::blur(cairo_surface_t *surface, int radius) {
  */
 
 NAN_METHOD(Context2d::New) {
+  if (!info.IsConstructCall()) {
+    return Nan::ThrowTypeError("Class constructors cannot be invoked without 'new'");
+  }
+
   Local<Object> obj = info[0]->ToObject();
   if (!Nan::New(Canvas::constructor)->HasInstance(obj))
     return Nan::ThrowTypeError("Canvas expected");

src/FontFace.cc

@@ -53,6 +53,10 @@ static cairo_user_data_key_t key;
  */
 
 NAN_METHOD(FontFace::New) {
+  if (!info.IsConstructCall()) {
+    return Nan::ThrowTypeError("Class constructors cannot be invoked without 'new'");
+  }
+
   if (!info[0]->IsString()
     || !info[1]->IsNumber()) {
     return Nan::ThrowError("Wrong argument types passed to FontFace constructor");
@@ -107,4 +111,3 @@ NAN_METHOD(FontFace::New) {
   face->Wrap(info.This());
   info.GetReturnValue().Set(info.This());
 }
-

src/Image.cc

@@ -67,6 +67,10 @@ Image::Initialize(Nan::ADDON_REGISTER_FUNCTION_ARGS_TYPE target) {
  */
 
 NAN_METHOD(Image::New) {
+  if (!info.IsConstructCall()) {
+    return Nan::ThrowTypeError("Class constructors cannot be invoked without 'new'");
+  }
+
   Image *img = new Image;
   img->data_mode = DATA_IMAGE;
   img->Wrap(info.This());

src/ImageData.cc

@@ -35,6 +35,10 @@ ImageData::Initialize(Nan::ADDON_REGISTER_FUNCTION_ARGS_TYPE target) {
  */
 
 NAN_METHOD(ImageData::New) {
+  if (!info.IsConstructCall()) {
+    return Nan::ThrowTypeError("Class constructors cannot be invoked without 'new'");
+  }
+
 #if NODE_MAJOR_VERSION == 0 && NODE_MINOR_VERSION <= 10
   Local<v8::Object> clampedArray;
   Local<Object> global = Context::GetCurrent()->Global();

test/canvas.test.js

@@ -12,6 +12,10 @@ console.log('   canvas: %s', Canvas.version);
 console.log('   cairo: %s', Canvas.cairoVersion);
 
 describe('Canvas', function () {
+  it('should require new', function () {
+    assert.throws(function () { Canvas(); }, TypeError);
+  });
+
   it('.version', function () {
     assert.ok(/^\d+\.\d+\.\d+$/.test(Canvas.version));
   });

test/image.test.js

@@ -11,6 +11,10 @@ var png_checkers = __dirname + '/fixtures/checkers.png';
 var png_clock = __dirname + '/fixtures/clock.png';
 
 describe('Image', function () {
+  it('should require new', function () {
+    assert.throws(function () { Image(); }, TypeError);
+  });
+
   it('Image', function () {
     assert.ok(Image instanceof Function);
   });

test/imageData.test.js

@@ -5,6 +5,10 @@ var Canvas = require('../')
     , assert = require('assert');
 
 describe('ImageData', function () {
+  it('should require new', function () {
+    assert.throws(function () { ImageData(); }, TypeError);
+  });
+
   it('should throw with invalid numeric arguments', function () {
       assert.throws(function () {
         new ImageData(0, 0);