bug#6609: 23.2; Cursor becomes invisible when put over some faces

[Deniz Dogan <deniz.a.m.dogan@gmail.com>]

2010/7/11 Eli Zaretskii <eliz@gnu.org>:
>> From: Deniz Dogan <deniz.a.m.dogan@gmail.com>
>> Date: Sun, 11 Jul 2010 13:25:03 +0200
>> Cc:
>>
>> I'm using Windows 7 and GNU Emacs 23.2.1 (i386-mingw-nt6.1.7600) of
>> 2010-05-08 on G41R2F1.
>>
>> Steps to reproduce:
>> 1. Make the following the only contents of your .emacs:
>> (set-foreground-color "black")
>> (set-background-color "white")
>> 2. Move the cursor over text with the "default" face.
>> 3. Notice how the cursor is now effectively invisible.
>
> What exactly does "effectively invisible" mean?  Do you see it or not?
> How about a screenshot?
>

I don't see it. I would screenshot it if there was anything to be seen.

>> This happens on Windows Vista as well.
>>
>> It also seems to happen when text has the "button" face, as seen in
>> e.g. the *Help* buffer sometimes.
>
> I can reproduce neither of these on Windows XP.  (I don't have access
> to W7 or Vista with development environment.)
>
> What does Emacs show if you type "M-x describe-face RET cursor RET"?
>

Face: cursor (sample) (customize this face)

Documentation:
Basic face for the cursor color under X.
Note: Other faces cannot inherit from the cursor face.

Defined in `faces.el'.

        Family: unspecified
       Foundry: unspecified
         Width: unspecified
        Height: unspecified
        Weight: unspecified
         Slant: unspecified
    Foreground: unspecified
    Background: unspecified
     Underline: unspecified
      Overline: unspecified
Strike-through: unspecified
           Box: unspecified
       Inverse: unspecified
       Stipple: unspecified
          Font: unspecified
       Fontset: unspecified
       Inherit: unspecified

> Do you have some non-standard color schemes defined on those systems?
>

No, I downloaded Emacs from the official FTP server and just added
set-background-color and set-foreground-color to my Emacs.

I can reproduce it on my system like this:

1. runemacs.exe -Q
2. Evaluate (progn (set-background-color "black")
(set-foreground-color "white"))
3. Notice how the cursor is not displayed when put over e.g. an ending
parenthesis.
4. Notice how the cursor *is* displayed when put over e.g. "progn"
(assuming we're in the *scratch* buffer or any buffer with
lisp-interaction-mode and font locking turned on).

-- 
Deniz Dogan