[pango/simple-fontmap: 24/31] Add a PangoFcHbFontMap test

[Matthias Clasen <matthiasc src gnome org>]

commit a9c9778c01d9190809fd0141dfdfa254537226e1
Author: Matthias Clasen <mclasen redhat com>
Date:   Sat Jan 1 17:44:46 2022 -0500

    Add a PangoFcHbFontMap test

 pango/pangofc-hbfontmap.c |  15 ++-----
 tests/testhbfont.c        | 110 ++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 114 insertions(+), 11 deletions(-)
---
diff --git a/pango/pangofc-hbfontmap.c b/pango/pangofc-hbfontmap.c
index 45e7adfe..0ce9d1d5 100644
--- a/pango/pangofc-hbfontmap.c
+++ b/pango/pangofc-hbfontmap.c
@@ -289,7 +289,6 @@ pango_hb_face_from_pattern (PangoFcHbFontMap *self,
   int instance_id;
   PangoFontDescription *description;
   const char *name;
-  PangoHbFace *orig;
   PangoHbFace *face;
   PangoMatrix font_matrix;
   FcLangSet *langs;
@@ -319,11 +318,7 @@ pango_hb_face_from_pattern (PangoFcHbFontMap *self,
   description = pango_font_description_from_pattern (pattern);
   name = style_name_from_pattern (pattern);
 
-  orig = find_face_by_file (self, family_name, file, index);
-  if (orig)
-    face = pango_hb_face_new_variant (orig, instance_id, NULL, FALSE, description);
-  else
-    face = pango_hb_face_new_from_file (file, index, instance_id, name, description);
+  face = pango_hb_face_new_from_file (file, index, instance_id, name, description);
 
   pango_font_description_free (description);
 
@@ -466,6 +461,7 @@ pango_fc_hb_font_map_populate (PangoHbFontMap *map)
           FcLangSet *langs;
           int spacing;
           const char *family_name;
+          const char *name;
 
           pat = ret->fonts[j];
 
@@ -504,12 +500,9 @@ pango_fc_hb_font_map_populate (PangoHbFontMap *map)
 
           desc = pango_font_description_new ();
           pango_font_description_set_family (desc, generic_names[i]);
+          name = pango_font_face_get_face_name (PANGO_FONT_FACE (face));
           pango_hb_font_map_add_face (PANGO_HB_FONT_MAP (self),
-                                      pango_hb_face_new_variant (PANGO_HB_FACE (face),
-                                                                 0xffff,
-                                                                 NULL,
-                                                                 FALSE,
-                                                                 desc));
+                                      pango_hb_face_new_synthetic (face, NULL, FALSE, name, desc));
           pango_font_description_free (desc);
 
           n_faces++;
diff --git a/tests/testhbfont.c b/tests/testhbfont.c
index 70004c4c..2264e1af 100644
--- a/tests/testhbfont.c
+++ b/tests/testhbfont.c
@@ -22,6 +22,7 @@
 #include "config.h"
 #include <glib.h>
 #include <pango/pangocairo.h>
+#include <pango/pangofc-hbfontmap.h>
 
 #include <hb-ot.h>
 
@@ -424,6 +425,113 @@ test_hbfont_load (void)
   g_object_unref (map);
 }
 
+/* Test font -> description -> font roundtrips with variations */
+static void
+test_hbfont_load_variation (void)
+{
+  PangoHbFontMap *map;
+  PangoContext *context;
+  char *path;
+  PangoFontDescription *desc;
+  PangoHbFace *face_fat, *face_wild;
+  char *s;
+  PangoFont *font;
+  hb_variation_t v;
+  hb_font_t *hb_font;
+  const float *coords;
+  unsigned int length;
+
+  /* Make a Cat family, with the two faces Fat and Wild */
+  map = pango_hb_font_map_new ();
+  context = pango_font_map_create_context (PANGO_FONT_MAP (map));
+
+  path = g_test_build_filename (G_TEST_DIST, "fonts", "Cantarell-VF.otf", NULL);
+  desc = pango_font_description_new ();
+  pango_font_description_set_family (desc, "Cat");
+  face_fat = pango_hb_face_new_from_file (path, 0, -1, "Fat", desc);
+  pango_font_description_free (desc);
+  g_free (path);
+
+  pango_hb_font_map_add_face (map, face_fat);
+
+  desc = pango_font_description_new ();
+  pango_font_description_set_family (desc, "Cat");
+  v.tag = HB_OT_TAG_VAR_AXIS_WEIGHT;
+  v.value = 624.;
+  face_wild = pango_hb_face_new_instance (face_fat, &v, 1, "Wild", desc);
+  pango_font_description_free (desc);
+
+  pango_hb_font_map_add_face (map, face_wild);
+
+  desc = pango_font_face_describe (PANGO_FONT_FACE (face_wild));
+
+  g_assert_cmpstr (pango_font_description_get_variations (desc), ==, "wght=624");
+
+  pango_font_description_set_size (desc, 12 * PANGO_SCALE);
+
+  s = pango_font_description_to_string (desc);
+  g_assert_cmpstr (s, ==, "Cat 12 @faceid=hb:Cantarell-Regular:0:-1:0:1:1:0:wght_624,wght=624");
+  g_free (s);
+
+  font = pango_font_map_load_font (PANGO_FONT_MAP (map), context, desc);
+  g_assert_true (pango_font_get_face (font) == PANGO_FONT_FACE (face_wild));
+
+  hb_font = pango_font_get_hb_font (font);
+  coords = hb_font_get_var_coords_design (hb_font, &length);
+  g_assert_cmpint (length, ==, 1);
+  g_assert_cmphex (coords[0], ==, 624.);
+
+  g_object_unref (font);
+
+  pango_font_description_free (desc);
+
+  g_object_unref (context);
+  g_object_unref (map);
+}
+
+/* Verify that pango_fontmap_load_fontset produces a non-empty result
+ * even if the language isn't covered - our itemization code relies
+ * on this.
+ */
+static gboolean
+get_font (PangoFontset *fontset,
+          PangoFont    *font,
+          gpointer      data)
+{
+  gboolean *found = data;
+
+  *found = TRUE;
+
+  return TRUE;
+}
+
+static void
+test_hbfont_language (void)
+{
+  PangoFontMap *map;
+  PangoContext *context;
+  PangoFontDescription *desc;
+  PangoFontset *fonts;
+  gboolean found;
+
+  map = PANGO_FONT_MAP (pango_fc_hb_font_map_new ());
+  context = pango_font_map_create_context (map);
+  desc = pango_font_description_from_string ("serif 11");
+
+  /* zz isn't assigned, so there should not be any fonts claiming to support
+   * this language. We are expecting to get a nonempty fontset regardless.
+   */
+  fonts = pango_font_map_load_fontset (map, context, desc, pango_language_from_string ("zz"));
+  g_assert_true (PANGO_IS_FONTSET (fonts));
+
+  found = FALSE;
+  pango_fontset_foreach (fonts, get_font, &found);
+  g_assert_true (found);
+
+  g_object_unref (fonts);
+  pango_font_description_free (desc);
+}
+
 int
 main (int argc, char *argv[])
 {
@@ -436,6 +544,8 @@ main (int argc, char *argv[])
   g_test_add_func ("/hbfont/describe/variation", test_hbfont_describe_variation);
   g_test_add_func ("/hbfont/faceid", test_hbfont_faceid);
   g_test_add_func ("/hbfont/load", test_hbfont_load);
+  g_test_add_func ("/hbfont/load/variation", test_hbfont_load_variation);
+  g_test_add_func ("/hbfont/language", test_hbfont_language);
 
   return g_test_run ();
 }