I was testing the latest version of the Snapshot, 15w32c, on creative mode and I found that dual wielding does not work as it should. When I'm holding a sword on my right hand and a bow on my left hand (With arrows on my inventory) and press the right button or "action" button on my mouse the bow will not fire and, instead, the sword will block. The same problem happens on Survival mode.
Environment
OSX Yosemite, Intel HD Graphics 4000 1024 mb, 4 GB 1600 MHz DDR3, 2,5 GHz Intel Core i5, Playing on window mode, Java version 8 actualization 31
Duplicate of MC-82923. Works as intended.