[gtk/backports-for-4-4: 1/16] textview: Apply font features from css

[Matthias Clasen <matthiasc src gnome org>]

commit 6ad047ab798f7d524bd6379b15d3e9d661f8b454
Author: Matthias Clasen <mclasen redhat com>
Date:   Thu Aug 26 20:21:23 2021 -0400

    textview: Apply font features from css
    
    We were forgetting to propagate these values from
    CSS to the default attributes. Share the code for
    getting these values out of a GtkCssStyle.

 gtk/gtkcssstyle.c        | 121 ++++++++++++++++++++++++++---------------------
 gtk/gtkcssstyleprivate.h |   6 +--
 gtk/gtktextview.c        |  10 +++-
 3 files changed, 77 insertions(+), 60 deletions(-)
---
diff --git a/gtk/gtkcssstyle.c b/gtk/gtkcssstyle.c
index 0f890a005d..03e58ab027 100644
--- a/gtk/gtkcssstyle.c
+++ b/gtk/gtkcssstyle.c
@@ -428,64 +428,14 @@ append_separated (GString    **s,
   g_string_append (*s, text);
 }
 
-PangoAttrList *
-gtk_css_style_get_pango_attributes (GtkCssStyle *style)
+char *
+gtk_css_style_compute_font_features (GtkCssStyle *style)
 {
-  PangoAttrList *attrs = NULL;
-  GtkTextDecorationLine decoration_line;
-  GtkTextDecorationStyle decoration_style;
-  const GdkRGBA *color;
-  const GdkRGBA *decoration_color;
-  int letter_spacing;
   GtkCssFontVariantLigature ligatures;
   GtkCssFontVariantNumeric numeric;
   GtkCssFontVariantEastAsian east_asian;
-  GString *s;
   char *settings;
-
-  /* text-decoration */
-  decoration_line = _gtk_css_text_decoration_line_value_get (style->font_variant->text_decoration_line);
-  decoration_style = _gtk_css_text_decoration_style_value_get (style->font_variant->text_decoration_style);
-  color = gtk_css_color_value_get_rgba (style->core->color);
-  decoration_color = gtk_css_color_value_get_rgba (style->font_variant->text_decoration_color
-                                                   ? style->font_variant->text_decoration_color
-                                                   : style->core->color);
-
-  if (decoration_line & GTK_CSS_TEXT_DECORATION_LINE_UNDERLINE)
-    {
-      attrs = add_pango_attr (attrs, pango_attr_underline_new (get_pango_underline_from_style 
(decoration_style)));
-      if (!gdk_rgba_equal (color, decoration_color))
-        attrs = add_pango_attr (attrs, pango_attr_underline_color_new (decoration_color->red * 65535. + 0.5,
-                                                                       decoration_color->green * 65535. + 
0.5,
-                                                                       decoration_color->blue * 65535. + 
0.5));
-    }
-  if (decoration_line & GTK_CSS_TEXT_DECORATION_LINE_OVERLINE)
-    {
-      attrs = add_pango_attr (attrs, pango_attr_overline_new (get_pango_overline_from_style 
(decoration_style)));
-      if (!gdk_rgba_equal (color, decoration_color))
-        attrs = add_pango_attr (attrs, pango_attr_overline_color_new (decoration_color->red * 65535. + 0.5,
-                                                                      decoration_color->green * 65535. + 0.5,
-                                                                      decoration_color->blue * 65535. + 
0.5));
-    }
-  if (decoration_line & GTK_CSS_TEXT_DECORATION_LINE_LINE_THROUGH)
-    {
-      attrs = add_pango_attr (attrs, pango_attr_strikethrough_new (TRUE));
-      if (!gdk_rgba_equal (color, decoration_color))
-        attrs = add_pango_attr (attrs, pango_attr_strikethrough_color_new (decoration_color->red * 65535. + 
0.5,
-                                                                           decoration_color->green * 65535. 
+ 0.5,
-                                                                           decoration_color->blue * 65535. + 
0.5));
-    }
-
-  /* letter-spacing */
-  letter_spacing = _gtk_css_number_value_get (style->font->letter_spacing, 100);
-  if (letter_spacing != 0)
-    {
-      attrs = add_pango_attr (attrs, pango_attr_letter_spacing_new (letter_spacing * PANGO_SCALE));
-    }
-
-  /* OpenType features */
-
-  s = NULL;
+  GString *s = NULL;
 
   switch (_gtk_css_font_kerning_value_get (style->font_variant->font_kerning))
     {
@@ -635,11 +585,72 @@ gtk_css_style_get_pango_attributes (GtkCssStyle *style)
     }
 
   if (s)
+    return g_string_free (s, FALSE);
+  else
+    return NULL;
+}
+
+PangoAttrList *
+gtk_css_style_get_pango_attributes (GtkCssStyle *style)
+{
+  PangoAttrList *attrs = NULL;
+  GtkTextDecorationLine decoration_line;
+  GtkTextDecorationStyle decoration_style;
+  const GdkRGBA *color;
+  const GdkRGBA *decoration_color;
+  int letter_spacing;
+
+  /* text-decoration */
+  decoration_line = _gtk_css_text_decoration_line_value_get (style->font_variant->text_decoration_line);
+  decoration_style = _gtk_css_text_decoration_style_value_get (style->font_variant->text_decoration_style);
+  color = gtk_css_color_value_get_rgba (style->core->color);
+  decoration_color = gtk_css_color_value_get_rgba (style->font_variant->text_decoration_color
+                                                   ? style->font_variant->text_decoration_color
+                                                   : style->core->color);
+
+  if (decoration_line & GTK_CSS_TEXT_DECORATION_LINE_UNDERLINE)
     {
-      attrs = add_pango_attr (attrs, pango_attr_font_features_new (s->str));
-      g_string_free (s, TRUE);
+      attrs = add_pango_attr (attrs, pango_attr_underline_new (get_pango_underline_from_style 
(decoration_style)));
+      if (!gdk_rgba_equal (color, decoration_color))
+        attrs = add_pango_attr (attrs, pango_attr_underline_color_new (decoration_color->red * 65535. + 0.5,
+                                                                       decoration_color->green * 65535. + 
0.5,
+                                                                       decoration_color->blue * 65535. + 
0.5));
+    }
+  if (decoration_line & GTK_CSS_TEXT_DECORATION_LINE_OVERLINE)
+    {
+      attrs = add_pango_attr (attrs, pango_attr_overline_new (get_pango_overline_from_style 
(decoration_style)));
+      if (!gdk_rgba_equal (color, decoration_color))
+        attrs = add_pango_attr (attrs, pango_attr_overline_color_new (decoration_color->red * 65535. + 0.5,
+                                                                      decoration_color->green * 65535. + 0.5,
+                                                                      decoration_color->blue * 65535. + 
0.5));
+    }
+  if (decoration_line & GTK_CSS_TEXT_DECORATION_LINE_LINE_THROUGH)
+    {
+      attrs = add_pango_attr (attrs, pango_attr_strikethrough_new (TRUE));
+      if (!gdk_rgba_equal (color, decoration_color))
+        attrs = add_pango_attr (attrs, pango_attr_strikethrough_color_new (decoration_color->red * 65535. + 
0.5,
+                                                                           decoration_color->green * 65535. 
+ 0.5,
+                                                                           decoration_color->blue * 65535. + 
0.5));
     }
 
+  /* letter-spacing */
+  letter_spacing = _gtk_css_number_value_get (style->font->letter_spacing, 100);
+  if (letter_spacing != 0)
+    {
+      attrs = add_pango_attr (attrs, pango_attr_letter_spacing_new (letter_spacing * PANGO_SCALE));
+    }
+
+  /* OpenType features */
+  {
+    char *font_features = gtk_css_style_compute_font_features (style);
+
+    if (font_features)
+      {
+        attrs = add_pango_attr (attrs, pango_attr_font_features_new (font_features));
+        g_free (font_features);
+      }
+  }
+
   return attrs;
 }
 
diff --git a/gtk/gtkcssstyleprivate.h b/gtk/gtkcssstyleprivate.h
index 27666e9978..2bbf72058e 100644
--- a/gtk/gtkcssstyleprivate.h
+++ b/gtk/gtkcssstyleprivate.h
@@ -254,17 +254,17 @@ GtkCssValue *           gtk_css_style_get_value                 (GtkCssStyle
 GtkCssSection *         gtk_css_style_get_section               (GtkCssStyle            *style,
                                                                  guint                   id) G_GNUC_PURE;
 gboolean                gtk_css_style_is_static                 (GtkCssStyle            *style) G_GNUC_PURE;
+GtkCssStaticStyle *     gtk_css_style_get_static_style          (GtkCssStyle            *style);
 
 char *                  gtk_css_style_to_string                 (GtkCssStyle            *style);
 gboolean                gtk_css_style_print                     (GtkCssStyle            *style,
                                                                  GString                *string,
                                                                  guint                   indent,
                                                                  gboolean                skip_initial);
-PangoAttrList *         gtk_css_style_get_pango_attributes      (GtkCssStyle            *style);
 
+char *                  gtk_css_style_compute_font_features     (GtkCssStyle            *style);
+PangoAttrList *         gtk_css_style_get_pango_attributes      (GtkCssStyle            *style);
 PangoFontDescription *  gtk_css_style_get_pango_font            (GtkCssStyle            *style);
-GtkCssStaticStyle *     gtk_css_style_get_static_style          (GtkCssStyle            *style);
-
 
 GtkCssValues *gtk_css_values_new   (GtkCssValuesType  type);
 GtkCssValues *gtk_css_values_ref   (GtkCssValues     *values);
diff --git a/gtk/gtktextview.c b/gtk/gtktextview.c
index fa085d0154..e37d44c722 100644
--- a/gtk/gtktextview.c
+++ b/gtk/gtktextview.c
@@ -57,7 +57,6 @@
 #include "gtknative.h"
 #include "gtkwidgetprivate.h"
 #include "gtkjoinedmenuprivate.h"
-#include "gtkcsslineheightvalueprivate.h"
 #include "gtkcssenumvalueprivate.h"
 
 /**
@@ -7667,7 +7666,6 @@ gtk_text_view_set_attributes_from_style (GtkTextView        *text_view,
   const GdkRGBA black = { 0, };
   const GdkRGBA *color;
   const GdkRGBA *decoration_color;
-  double height;
   GtkTextDecorationLine decoration_line;
   GtkTextDecorationStyle decoration_style;
 
@@ -7691,6 +7689,7 @@ gtk_text_view_set_attributes_from_style (GtkTextView        *text_view,
   values->letter_spacing = _gtk_css_number_value_get (style->font->letter_spacing, 100) * PANGO_SCALE;
 
   /* text-decoration */
+
   decoration_line = _gtk_css_text_decoration_line_value_get (style->font_variant->text_decoration_line);
   decoration_style = _gtk_css_text_decoration_style_value_get (style->font_variant->text_decoration_style);
   color = gtk_css_color_value_get_rgba (style->core->color);
@@ -7742,6 +7741,13 @@ gtk_text_view_set_attributes_from_style (GtkTextView        *text_view,
       gdk_rgba_free (values->appearance.strikethrough_rgba);
       values->appearance.strikethrough_rgba = NULL;
     }
+
+  /* letter-spacing */
+  values->letter_spacing = _gtk_css_number_value_get (style->font->letter_spacing, 100) * PANGO_SCALE;
+
+  /* OpenType features */
+  g_free (values->font_features);
+  values->font_features = gtk_css_style_compute_font_features (style);
 }
 
 static void