Merge pull request #615 from CartoDB/dont-remove-callbacks-after-call

Don't unbind onload/onerror callbacks after invoking them

src/Image.cc

@@ -357,8 +357,6 @@ Image::loaded() {
 
   if (onload != NULL) {
     onload->Call(0, NULL);
-    delete onload;
-    onload = NULL;
   }
 }
 
@@ -372,8 +370,6 @@ Image::error(Local<Value> err) {
   if (onerror != NULL) {
     Local<Value> argv[1] = { err };
     onerror->Call(1, argv);
-    delete onerror;
-    onerror = NULL;
   }
 }
 

test/image.test.js

@@ -7,7 +7,8 @@ var Canvas = require('../')
   , Image = Canvas.Image
   , assert = require('assert');
 
-var png = __dirname + '/fixtures/clock.png';
+var png_checkers = __dirname + '/fixtures/checkers.png';
+var png_clock = __dirname + '/fixtures/clock.png';
 
 describe('Image', function () {
   it('Image', function () {
@@ -23,18 +24,48 @@ describe('Image', function () {
 
     img.onload = function () {
       onloadCalled += 1;
-      assert.strictEqual(img.src, png);
+      assert.strictEqual(img.src, png_clock);
     };
 
-    img.src = png;
+    img.src = png_clock;
     assert.strictEqual(1, onloadCalled);
-    assert.strictEqual(img.src, png);
+    assert.strictEqual(img.src, png_clock);
 
     assert.strictEqual(true, img.complete);
     assert.strictEqual(320, img.width);
     assert.strictEqual(320, img.height);
   });
 
+  it('test Image#onload multiple times', function() {
+    var img = new Image
+      , onloadCalled = 0;
+
+    img.onload = function() {
+      onloadCalled += 1;
+    };
+
+    img.src = png_checkers;
+    assert.equal(img.src, png_checkers);
+    assert.strictEqual(true, img.complete);
+    assert.strictEqual(2, img.width);
+    assert.strictEqual(2, img.height);
+
+    img.src = png_clock;
+    assert.equal(img.src, png_clock);
+    assert.strictEqual(true, img.complete);
+    assert.strictEqual(320, img.width);
+    assert.strictEqual(320, img.height);
+
+    assert.equal(onloadCalled, 2);
+
+    onloadCalled = 0;
+    img.onload = function() {
+      onloadCalled += 1;
+    };
+    img.src = png_clock;
+    assert.equal(onloadCalled, 1);
+  });
+
   it('Image#onerror', function () {
     var img = new Image
       , error
@@ -53,18 +84,48 @@ describe('Image', function () {
     };
 
     try {
-      img.src = png + 's';
+      img.src = png_clock + 's';
     } catch (err) {
       assert.fail('error did not invoke onerror(): ' + err);
     }
 
     assert.strictEqual(1, onerrorCalled);
-    assert.strictEqual(img.src, png + 's');
+    assert.strictEqual(img.src, png_clock + 's');
     assert.strictEqual(false, img.complete);
 
     assert.ok(error instanceof Error, 'did not invoke onerror() with error');
   });
 
+  it('test Image#onerror multiple calls', function() {
+    var img = new Image
+      , onerrorCalled = 0;
+
+
+    img.onload = function() {
+      assert.fail('called onload');
+    };
+
+    img.onerror = function() {
+      onerrorCalled += 1;
+    };
+
+    img.src = png_clock + 's1';
+    assert.equal(img.src, png_clock + 's1');
+
+    img.src = png_clock + 's2';
+    assert.equal(img.src, png_clock + 's2');
+
+    assert.equal(onerrorCalled, 2);
+
+    onerrorCalled = 0;
+    img.onerror = function() {
+      onerrorCalled += 1;
+    };
+    img.src = png_clock + 's3';
+    assert.equal(img.src, png_clock + 's3');
+    assert.equal(onerrorCalled, 1);
+  });
+
   it('Image#{width,height}', function () {
     var img = new Image
       , onloadCalled = 0;
@@ -78,7 +139,7 @@ describe('Image', function () {
       assert.strictEqual(320, img.height);
     };
 
-    img.src = png;
+    img.src = png_clock;
     assert.strictEqual(1, onloadCalled);
     assert.strictEqual(320, img.width);
     assert.strictEqual(320, img.height);