Bug compatible?

[Huw D M Davies]

On Mon, Feb 09, 2004 at 09:00:45AM +1100, Troy Rollo wrote:
> On Sat, 7 Feb 2004 00:51, Fabian Cenedese wrote:
> > GetTextExtentPointA/W:
> > TRACE("not bug compatible.");
> >
> > As funny as it is it doesn't say that much. Is this referring to a bug
> > in Windows?
> 
> Actually, it does say much.
> 
> Bug compatibility is defined in TNHD (or the jargon file as it's often named 
> these days). This means there's a bug in some versions of Windows that has 
> not been translated to Wine. My guess is that the bug referred to here is one 
> that causes GetTextExtent* to sometimes return a width of zero for non-empty 
> strings. The bug has no practical uses, and although plenty of apps no doubt 
> work around it, the work-around is to detect if the width component is zero, 
> and then futz around with the string to try to figure out what the return 
> value really should have been. It is extremely unlikely that the lack of 
> compatibility with this bug would break any Windows app, particularly since 
> the bug is not present in all versions of Windows.
> 
> In fact, there would appear to be no sensible way for an app to rely on the 
> presence of a bug in these API calls. In other cases, however, an app might 
> rely on the buggy behaviour of a particular API call, and then bug 
> compatibility can be important.
> 
> It seems to me that all this is saying is "this isn't bug compatible, but it 
> wasn't thought that it would be useful to emulate Microsoft bugs here".

Interesting.  Any chance of a regression test that shows this behaviour?

Huw.