- Electron version: 1.3.5
- Operating system: macOS/Windows

Alt-clicking a link is a default shortcut for downloading a file without a save prompt, and we make use of it in our app. But for links that end in a trailing slash, the resulting filename isn't consistent with the default file name in the save prompt.

The save prompt constructs a name from the word "download" and the extension for the mime type of the file, but the prompt-less savepath is just the domain name of the link. This leads to unusable files (e.g. with a .com file extension) being saved to the filesystem.

Here's my current workaround, but given the prompt does get a useful path, and Chrome behaves correctly, I imagine this might be straightforward to fix if you know where to look:

``` javascript
const mime = require('mime-types');
const _ = require('lodash');
const path = require('path');
const unusedFilename = require('unused-filename');

win.webContents.session.on('will-download', function (e, item, webContents) {
  if (item.getSavePath() && _.last(item.getURL()) === '/') {
      var savePath = unusedFilename.sync(path.format({
        dir: path.dirname(item.getSavePath()),
        name: 'download',
        ext: '.' + mime.extension(item.getMimeType())
      }));
      item.setSavePath(savePath);
    }
});
```

atom/browser/api/atom_api_download_item.cc
content::DownloadItem* download_item)
    : download_item_(download_item) {
  download_item_->AddObserver(this);
  Init(isolate);
  AttachAsUserData(download_item);
}
DownloadItem::~DownloadItem() {
  if (download_item_) {
    
    download_item_->RemoveObserver(this);
    download_item_->Remove();
  }
  
  g_download_item_objects.erase(weak_map_id());
}
void DownloadItem::OnDownloadUpdated(content::DownloadItem* item) {
  if (download_item_->IsDone()) {
    Emit("done", item->GetState());
    
    base::MessageLoop::current()->PostTask(FROM_HERE, GetDestroyClosure());
  } else {
    Emit("updated", item->GetState());
  }
}
void DownloadItem::OnDownloadDestroyed(content::DownloadItem* download_item) {