Bug: Border does not render if background is transparent

[bryphe]

Issue: If a border is specified, but no background, the border does not render.

For example, for this component:

module Test = (
  val component((render, ~children, ()) =>
        render(
          () => {
            let borderStyle =
              Style.make(
                ~border=Style.Border.make(~width=10, ~color=Colors.white, ()),
                (),
              );

            let innerStyle =
                Style.make(
                    ~backgroundColor=Colors.red,
                    ~width=100,
                    ~height=100,
                    (),
                );

              <view style=borderStyle>
                  <view style=innerStyle />
              </view>
          },
          ~children,
        )
      )
);

I would expect to see this:

But get:

I actually hit this in #138 , which is why I added a pretty transparent background here:
https://github.com/bryphe/revery/blob/d05c343e67c90b81fdc19da74fbf59b5e6a87536/examples/Bin.re#L113

The issue seems to be this check: https://github.com/bryphe/revery/blob/d05c343e67c90b81fdc19da74fbf59b5e6a87536/src/UI/ViewNode.re#L241

[OhadRau]

Whoops, I think in my head I was looking at that c.a as style.opacity when I went back to check that code. I'll fix this real quick

[bryphe]

Fixed by #147 - thanks @OhadRau !

[OhadRau]

I think this snuck back in when the box-shadows were merged...

[bryphe]

Ah, bummer - thanks for catching it @OhadRau . I'll reopen to track.

Also trying to think about ways to catch these sorts of regressions via CI - put some thoughts in #156

[OhadRau]

@bryphe @Akin909 Fixing this right now. Looks like shadows are currently going to be rendered only if the node's alpha > 0 (so essentially the same as this bug). Is this the desired behavior or should I make that happen regardless of the node's alpha?