[gtk/hex-color-parse: 2/2] rgba: Use pango_color_parse_with_alpha

[Matthias Clasen <matthiasc src gnome org>]

commit 1f3327d32622f84f1f10d3ed7d02cc60130f8084
Author: Matthias Clasen <mclasen redhat com>
Date:   Sun Aug 2 23:23:49 2020 -0400

    rgba: Use pango_color_parse_with_alpha
    
    Use this newly exported pango function, so we
    can support hex colors with alpha like #rrggbbaa.
    
    Fixes: #2931

 gdk/gdkrgba.c        | 15 +++++++++------
 testsuite/gdk/rgba.c |  8 ++++++++
 2 files changed, 17 insertions(+), 6 deletions(-)
---
diff --git a/gdk/gdkrgba.c b/gdk/gdkrgba.c
index 20940db9d3..fac9d2efa5 100644
--- a/gdk/gdkrgba.c
+++ b/gdk/gdkrgba.c
@@ -170,19 +170,21 @@ parse_rgb_value (const char   *str,
  * - A standard name (Taken from the X11 rgb.txt file).
  * - A hexadecimal value in the form “\#rgb”, “\#rrggbb”,
  *   “\#rrrgggbbb” or ”\#rrrrggggbbbb”
+ * - A hexadecimal value in the form “\#rgba”, “\#rrggbbaa”,
+ *   or ”\#rrrrggggbbbbaaaa”
  * - A RGB color in the form “rgb(r,g,b)” (In this case the color will
  *   have full opacity)
  * - A RGBA color in the form “rgba(r,g,b,a)”
  *
  * Where “r”, “g”, “b” and “a” are respectively the red, green, blue and
- * alpha color values. In the last two cases, “r”, “g”, and “b” are either integers
- * in the range 0 to 255 or percentage values in the range 0% to 100%, and
- * a is a floating point value in the range 0 to 1.
+ * alpha color values. In the last two cases, “r”, “g”, and “b” are either
+ * integers in the range 0 to 255 or percentage values in the range 0% to
+ * 100%, and a is a floating point value in the range 0 to 1.
  *
  * Returns: %TRUE if the parsing succeeded
  */
 gboolean
-gdk_rgba_parse (GdkRGBA     *rgba,
+gdk_rgba_parse (GdkRGBA    *rgba,
                 const char *spec)
 {
   gboolean has_alpha;
@@ -207,18 +209,19 @@ gdk_rgba_parse (GdkRGBA     *rgba,
   else
     {
       PangoColor pango_color;
+      guint16 alpha;
 
       /* Resort on PangoColor for rgb.txt color
        * map and '#' prefixed colors
        */
-      if (pango_color_parse (&pango_color, str))
+      if (pango_color_parse_with_alpha (&pango_color, &alpha, str))
         {
           if (rgba)
             {
               rgba->red = pango_color.red / 65535.;
               rgba->green = pango_color.green / 65535.;
               rgba->blue = pango_color.blue / 65535.;
-              rgba->alpha = 1;
+              rgba->alpha = alpha / 65535.;
             }
 
           return TRUE;
diff --git a/testsuite/gdk/rgba.c b/testsuite/gdk/rgba.c
index db3fbd3111..26a94655e2 100644
--- a/testsuite/gdk/rgba.c
+++ b/testsuite/gdk/rgba.c
@@ -57,6 +57,14 @@ test_color_parse (void)
   res = gdk_rgba_parse (&color, "rgb(0,0,0)");
   g_assert (res);
   g_assert (gdk_rgba_equal (&color, &expected));
+
+  expected.red = 0.0;
+  expected.green = 0x8080 / 65535.;
+  expected.blue = 1.0;
+  expected.alpha = 0x8888 / 65535.;
+  res = gdk_rgba_parse (&color, "#0080ff88");
+  g_assert (res);
+  g_assert (gdk_rgba_equal (&color, &expected));
 }
 
 static void