bug#13000: 24.2.90; underwave doesn't look as good as other IDEs

[Juri Linkov <juri@jurta.org>]

> I hope this new feature is done properly before users see it.

For users to take advantage of this new feature we could modify
the faces where it would be most useful like the patch below does.

One problem is how to handle the tty case.  On a tty frame
underwave underlines and doesn't use the color attribute.
So the question is what face condition to use to filter out
displays where underwave is not supported.

The already supported condition ((supports :underline t))
doesn't take into account the underwave attribute,
and a similar condition ((supports :underline wave))
is not implemented.

Thus the patch uses the condition ((class color) (min-colors 88))
to find the displays that should use the old face definitions
without underwave:

=== modified file 'lisp/progmodes/flymake.el'
--- lisp/progmodes/flymake.el	2012-11-12 08:42:27 +0000
+++ lisp/progmodes/flymake.el	2012-12-28 23:50:57 +0000
@@ -844,12 +844,18 @@ (defun flymake-region-has-flymake-overla
     has-flymake-overlays))
 
 (defface flymake-errline
-  '((t :inherit error))
+  '((((class color) (min-colors 88))
+     :underline (:color "Red1" :style wave))
+    (t
+     :inherit error))
   "Face used for marking error lines."
   :group 'flymake)
 
 (defface flymake-warnline
-  '((t :inherit warning))
+  '((((class color) (min-colors 88))
+     :underline (:color "DarkOrange" :style wave))
+    (t
+     :inherit warning))
   "Face used for marking warning lines."
   :group 'flymake)

=== modified file 'lisp/textmodes/flyspell.el'
--- lisp/textmodes/flyspell.el	2012-09-17 05:41:04 +0000
+++ lisp/textmodes/flyspell.el	2012-12-28 23:53:51 +0000
@@ -445,11 +445,19 @@ (make-variable-buffer-local 'flyspell-da
 ;;*---------------------------------------------------------------------*/
 ;;*    Highlighting                                                     */
 ;;*---------------------------------------------------------------------*/
-(defface flyspell-incorrect '((t :underline t :inherit error))
+(defface flyspell-incorrect
+  '((((class color) (min-colors 88))
+     :underline (:color "Red1" :style wave))
+    (t
+     :underline t :inherit error))
   "Flyspell face for misspelled words."
   :group 'flyspell)
 
-(defface flyspell-duplicate '((t :underline t :inherit warning))
+(defface flyspell-duplicate
+  '((((class color) (min-colors 88))
+     :underline (:color "DarkOrange" :style wave))
+    (t
+     :underline t :inherit warning))
   "Flyspell face for words that appear twice in a row.
 See also `flyspell-duplicate-distance'."
   :group 'flyspell)