feat(resize): don't resize if bounds haven't changed

lib/features/resize/Resize.js

@@ -122,10 +122,17 @@ export default function Resize(eventBus, rules, modeling, dragging) {
         newBounds = context.newBounds;
 
     if (canExecute) {
+
       // ensure we have actual pixel values for new bounds
       // (important when zoom level was > 1 during move)
       newBounds = roundBounds(newBounds);
 
+      if (!boundsChanged(shape, newBounds)) {
+
+        // no resize necessary
+        return;
+      }
+
       // perform the actual resize
       modeling.resizeShape(shape, newBounds);
     }
@@ -229,4 +236,13 @@ Resize.$inject = [
   'rules',
   'modeling',
   'dragging'
-];
+];
+
+// helpers //////////
+
+function boundsChanged(shape, newBounds) {
+  return shape.x !== newBounds.x ||
+    shape.y !== newBounds.y ||
+    shape.width !== newBounds.width ||
+    shape.height !== newBounds.height;
+}

test/spec/features/resize/ResizeSpec.js

@@ -1,3 +1,5 @@
+/* global sinon */
+
 import {
   bootstrapDiagram,
   inject
@@ -25,6 +27,8 @@ function bounds(b) {
   return pick(b, [ 'x', 'y', 'width', 'height' ]);
 }
 
+var spy = sinon.spy;
+
 describe('features/resize - Resize', function() {
 
   beforeEach(bootstrapDiagram({
@@ -203,6 +207,45 @@ describe('features/resize - Resize', function() {
       expect(shapeBounds).to.eql({ x: 100, y: 100, width: 80, height: 110 });
     }));
 
+
+    it('should NOT resize if bounds have not changed', inject(
+      function(canvas, dragging, elementFactory, modeling, resize) {
+
+        // given
+        var resizeShapeSpy = spy(modeling, 'resizeShape');
+
+        var shape = elementFactory.createShape({
+          id: 'shapeA',
+          resizable: 'always',
+          x: 100,
+          y: 100,
+          width: 100,
+          height: 100
+        });
+
+        shape = canvas.addShape(shape);
+
+        // when
+        resize.activate(canvasEvent({ x: 200, y: 200 }), shape, 'se');
+
+        dragging.move(canvasEvent({ x: 205, y: 205 }));
+
+        dragging.move(canvasEvent({ x: 200, y: 200 }));
+
+        dragging.end();
+
+        // then
+        expect(resizeShapeSpy).not.to.have.been.called;
+
+        expect(shape).to.have.bounds({
+          x: 100,
+          y: 100,
+          width: 100,
+          height: 100
+        });
+      }
+    ));
+
   });