[racket-dev] weirdest bug ever

At Thu, 17 Jan 2013 18:54:25 +0100, Pierpaolo Bernardi wrote:
> On Thu, Jan 17, 2013 at 4:46 PM, Ben Goetter <goetter at mazama.net> wrote:
> 
> > On Windows, Courier New (the default font for the drracket output pane) does
> > not support U+2144.  When I set the output pane to use a font that does
> > support this character, such as Segoe UI Symbol, U+2144 displays in the
> > correct bounding box, e.g. (display (string #\a (integer->char #x2144)
> > #\c)).  So it has something to do with how DrRacket on Windows switches
> > fonts to display symbol characters.
> 
> AHA! Now it's much less misterious.

In particular, the problem is in the implementation of the text editor,
which assumes (in `string-snip%', specifically) that the height and
descent of text is determined only by the font --- and that's not true
if a glyph is substituted from some other font.

We'll fix this, but probably not right away.