Re: [PATCH v3] oleacc: Add support for retrieving an HWND from accNavigate to WindowFromAccessibleObject.

[Connor McAdams]

On Mon, May 16, 2022 at 04:17:10PM +0200, Piotr Caban wrote:
> Hi Connor,
>
> On 5/13/22 18:43, Connor McAdams wrote:
> > @@ -155,7 +167,12 @@ static HRESULT WINAPI Accessible_get_accParent(
> >           IAccessible *iface, IDispatch **ppdispParent)
> >   {
> >       if(iface == &Accessible_child)
> > +    {
> >           CHECK_EXPECT(Accessible_child_get_accParent);
> > +        if (OleWindow_hwnd) > +            return
> > IAccessible_QueryInterface(&Accessible,
> > &IID_IDispatch,
> > +                    (void **)ppdispParent);
> > I don't understand this part. Why do you need to check OleWindow_hwnd? It
> > would probably make sense to return parent unconditionally.

Largely to gate returning a parent interface in other tests that call
get_accParent on Accessible_child. The idea was to only return a parent
interface for the WindowFromAccessibleObject tests where we're trying to
retrieve an HWND from the parent's IOleWindow interface.
> > +#define NAVDIR_INTERNAL_HWND 10
> >   static HRESULT WINAPI Accessible_accNavigate(IAccessible *iface,
> >           LONG navDir, VARIANT varStart, VARIANT *pvarEnd)
> >   {
> > -    ok(0, "unexpected call\n");
> > +    if(iface == &Accessible_child)
> > +        CHECK_EXPECT(Accessible_child_accNavigate);
> > +    else
> > +        CHECK_EXPECT(Accessible_accNavigate);
> > +
> > +    /*
> > +     * Magic number value for retrieving an HWND. Used by DynamicAnnotation
> > +     * IAccessible wrapper.
> > +     */
> > +    if(navDir == NAVDIR_INTERNAL_HWND) {
> > +        V_VT(pvarEnd) = VT_I4;
> > +        V_I4(pvarEnd) = HandleToULong(Accessible_accnav_hwnd);
> > +        return S_OK;
> > S_FALSE or E_INVALIDARG looks like a better return value when
> > Accessible_accnav_hwnd is NULL (unless there's value in testing S_OK). How
> > about changing Accessible_accnav_hwnd name to Accessible_hwnd?

I was mainly testing whether or not it'd accept returning a NULL hwnd,
or continue trying to use other methods to ascertain the HWND if NULL is
returned. I can try other return codes. As it is, it seems that if the
IAccessible doesn't have an IOleWindow interface, and the accNav method
returns a NULL hwnd, it goes up the parent chain. If the accNav method
returns a non-NULL hwnd, it returns immediately.
> > +static HRESULT WINAPI OleWindow_GetWindow(IOleWindow *iface, HWND *hwnd)
> > +{
> > +    *hwnd = OleWindow_hwnd;
> > +    return S_OK;
> > Again, I don't know if there's value in testing NULL HWND and S_OK return.
> > If not, documentation suggests returning E_FAIL.
>
> Thanks,
> Piotr

Sure. I can do E_FAIL here instead if the hwnd is NULL. I hadn't looked
at the IOleWindow documentation, guess I should have. :)

Thanks for the review.