[pango/no-font-fixes: 3/3] Add a test for no-fonts

[Matthias Clasen <matthiasc src gnome org>]

commit e27ac590d44e87adac235c1b63429dc5f832f782
Author: Matthias Clasen <mclasen redhat com>
Date:   Mon Sep 26 20:41:19 2022 -0400

    Add a test for no-fonts
    
    Test that the layout is made up entirely of unknown
    glyphs if we have no font. The main point of this
    test is to ensure that we don't crash if analysis->font
    is NULL.

 tests/meson.build        |   1 +
 tests/nofonts/fonts.conf |  71 ++++++++++++++++++++++++++++++
 tests/test-no-fonts.c    | 109 +++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 181 insertions(+)
---
diff --git a/tests/meson.build b/tests/meson.build
index e75b8e2f5..8b4bfa38e 100644
--- a/tests/meson.build
+++ b/tests/meson.build
@@ -63,6 +63,7 @@ if cairo_dep.found()
       tests += [
         [ 'test-layout', [ 'test-layout.c', 'test-common.c' ], [ libpangocairo_dep, libpangoft2_dep ] ],
         [ 'test-fonts', [ 'test-fonts.c', 'test-common.c' ], [ libpangocairo_dep, libpangoft2_dep ] ],
+        [ 'test-no-fonts', [ 'test-no-fonts.c' ], [ libpangocairo_dep, libpangoft2_dep ] ],
       ]
     endif
   endif
diff --git a/tests/nofonts/fonts.conf b/tests/nofonts/fonts.conf
new file mode 100644
index 000000000..156854217
--- /dev/null
+++ b/tests/nofonts/fonts.conf
@@ -0,0 +1,71 @@
+<?xml version="1.0"?>
+<!DOCTYPE fontconfig SYSTEM "urn:fontconfig:fonts.dtd">
+<fontconfig>
+  <cachedir>/tmp/cache</cachedir>
+
+  <match target="font">
+    <test name="outline" compare="eq">
+      <bool>false</bool>
+    </test>
+    <edit name="pixelsizefixupfactor" mode="assign">
+      <divide>
+        <name target="pattern">pixelsize</name>
+        <name target="font">pixelsize</name>
+      </divide>
+    </edit>
+  </match>
+
+  <match target="font">
+    <test name="outline" compare="eq">
+      <bool>false</bool>
+    </test>
+    <test name="pixelsizefixupfactor" compare="not_eq">
+      <double>1.0</double>
+    </test>
+    <edit name="matrix" mode="assign">
+      <times>
+        <name>matrix</name>
+        <matrix>
+          <name>pixelsizefixupfactor</name> <double>0</double>
+          <double>0</double> <name>pixelsizefixupfactor</name>
+         </matrix>
+      </times>
+    </edit>
+    <edit name="size" mode="assign">
+      <divide>
+        <name>size</name>
+        <name>pixelsizefixupfactor</name>
+      </divide>
+    </edit>
+  </match>
+
+  <alias binding="same">
+    <family>Noto Color Emoji</family>
+    <default><family>emoji</family></default>
+  </alias>
+
+  <match>
+    <test name="lang">
+      <string>und-zsye</string>
+    </test>
+    <test qual="all" name="family" compare="not_eq">
+      <string>emoji</string>
+    </test>
+    <edit name="family" mode="append" binding="strong">
+      <string>emoji</string>
+    </edit>
+  </match>
+
+  <alias binding="same">
+    <family>emoji</family>
+    <prefer>
+      <family>Noto Color Emoji</family>
+    </prefer>
+  </alias>
+
+  <alias>
+    <family>monospace</family>
+    <prefer><family>DejaVu Sans Mono</family></prefer>
+  </alias>
+
+</fontconfig>
diff --git a/tests/test-no-fonts.c b/tests/test-no-fonts.c
new file mode 100644
index 000000000..c057874d6
--- /dev/null
+++ b/tests/test-no-fonts.c
@@ -0,0 +1,109 @@
+/* Pango
+ * test-no-fonts.c: Check that lack of fonts is survivable
+ *
+ * Copyright (C) 2022 Red Hat, Inc
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.         See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#include <glib.h>
+#include <string.h>
+#include <locale.h>
+
+#ifndef G_OS_WIN32
+#include <unistd.h>
+#endif
+
+#include "config.h"
+#include <pango/pangocairo.h>
+#include <pango/pangocairo-fc.h>
+#include <pango/pangofc-fontmap.h>
+#include "test-common.h"
+
+
+static void
+install_fonts (const char *dir)
+{
+  FcConfig *config;
+  PangoFontMap *map;
+  char *path;
+  gsize len;
+  char *conf;
+
+  map = g_object_new (PANGO_TYPE_CAIRO_FC_FONT_MAP, NULL);
+
+  config = FcConfigCreate ();
+
+  path = g_build_filename (dir, "fonts.conf", NULL);
+  g_file_get_contents (path, &conf, &len, NULL);
+
+  if (!FcConfigParseAndLoadFromMemory (config, (const FcChar8 *) conf, TRUE))
+    g_error ("Failed to parse fontconfig configuration");
+
+  g_free (conf);
+  g_free (path);
+
+  FcConfigAppFontAddDir (config, (const FcChar8 *) dir);
+  pango_fc_font_map_set_config (PANGO_FC_FONT_MAP (map), config);
+  FcConfigDestroy (config);
+
+  pango_cairo_font_map_set_default (PANGO_CAIRO_FONT_MAP (map));
+
+  g_object_unref (map);
+}
+
+static void
+test_nofonts (void)
+{
+  PangoContext *context;
+  const char *text;
+  PangoLayout *layout;
+  int missing;
+
+  context = pango_font_map_create_context (pango_cairo_font_map_get_default ());
+  layout = pango_layout_new (context);
+
+  text = "Schlaf, Kindlein schlaf! "
+         "Der Vater hüt' die Schaf, "
+         "die Mutter schúttelt's Bäumelein, "
+         "da fällt herab ein Träumelein. "
+         "Schlaf, Kindlein schlaf!";
+
+  pango_layout_set_text (layout, text, -1);
+  missing = pango_layout_get_unknown_glyphs_count (layout);
+  g_assert_cmpint (missing, ==, g_utf8_strlen (text, -1));
+
+  g_object_unref (layout);
+  g_object_unref (context);
+}
+
+int
+main (int argc, char *argv[])
+{
+  char *path;
+
+  setlocale (LC_ALL, "");
+
+  g_test_init (&argc, &argv, NULL);
+
+  path = g_test_build_filename (G_TEST_DIST, "nofonts", NULL);
+  install_fonts (path);
+  g_free (path);
+
+  g_test_add_func ("/layout/nofonts", test_nofonts);
+
+  return g_test_run ();
+}