[gtk/svg-viewer] Add an svg test

[Matthias Clasen <matthiasc src gnome org>]

commit 29ba8f081938d80e242653715f4c698c2f05a262
Author: Matthias Clasen <mclasen redhat com>
Date:   Wed Aug 5 23:22:03 2020 -0400

    Add an svg test
    
    tests/testsvg is a minimal paintable implementation wrapped
    around RsvgHandle.

 tests/meson.build |   9 +++
 tests/testsvg.c   | 207 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 216 insertions(+)
---
diff --git a/tests/meson.build b/tests/meson.build
index 4618df6b97..c7a83bb7d1 100644
--- a/tests/meson.build
+++ b/tests/meson.build
@@ -140,3 +140,12 @@ if get_option('profiler')
   executable('testperf', 'testperf.c',
               dependencies: [profiler_dep, platform_gio_dep, libm])
 endif
+
+librsvg = dependency('librsvg-2.0', required: false)
+
+if librsvg.found()
+  executable('testsvg', 'testsvg.c',
+             include_directories: [confinc, gdkinc],
+             c_args: test_args + common_cflags,
+             dependencies: [libgtk_dep, librsvg, libm])
+endif
diff --git a/tests/testsvg.c b/tests/testsvg.c
new file mode 100644
index 0000000000..13c38a8228
--- /dev/null
+++ b/tests/testsvg.c
@@ -0,0 +1,207 @@
+/* testsvg.c
+ * Copyright (C) 2020 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, see <http://www.gnu.org/licenses/>.
+ */
+#include <gtk/gtk.h>
+#include <librsvg/rsvg.h>
+
+#define SVG_TYPE_PAINTABLE (svg_paintable_get_type ())
+
+G_DECLARE_FINAL_TYPE (SvgPaintable, svg_paintable, SVG, PAINTABLE, GObject)
+
+struct _SvgPaintable
+{
+  GObject parent_instance;
+  GFile *file;
+  RsvgHandle *handle;
+};
+
+struct _SvgPaintableClass
+{
+  GObjectClass parent_class;
+};
+
+enum {
+  PROP_FILE = 1,
+  NUM_PROPERTIES
+};
+
+static void
+svg_paintable_snapshot (GdkPaintable *paintable,
+                        GdkSnapshot  *snapshot,
+                        double        width,
+                        double        height)
+{
+  SvgPaintable *self = SVG_PAINTABLE (paintable);
+  cairo_t *cr;
+  GError *error = NULL;
+
+  cr = gtk_snapshot_append_cairo (GTK_SNAPSHOT (snapshot),
+                                  &GRAPHENE_RECT_INIT (0, 0, width, height));
+
+  if (!rsvg_handle_render_document (self->handle, cr,
+                                    &(RsvgRectangle) {0, 0, width, height},
+                                    &error))
+    {
+      g_error ("%s", error->message);
+    }
+
+  cairo_destroy (cr);
+}
+
+static void
+svg_paintable_init_interface (GdkPaintableInterface *iface)
+{
+  iface->snapshot = svg_paintable_snapshot;
+}
+
+G_DEFINE_TYPE_WITH_CODE (SvgPaintable, svg_paintable, G_TYPE_OBJECT,
+                         G_IMPLEMENT_INTERFACE (GDK_TYPE_PAINTABLE,
+                                                svg_paintable_init_interface))
+
+static void
+svg_paintable_init (SvgPaintable *self)
+{
+}
+
+static void
+svg_paintable_dispose (GObject *object)
+{
+  SvgPaintable *self = SVG_PAINTABLE (object);
+
+  g_clear_object (&self->file);
+  g_clear_object (&self->handle);
+
+  G_OBJECT_CLASS (svg_paintable_parent_class)->dispose (object);
+}
+
+static void
+svg_paintable_set_property (GObject      *object,
+                            guint         prop_id,
+                            const GValue *value,
+                            GParamSpec   *pspec)
+{
+  SvgPaintable *self = SVG_PAINTABLE (object);
+
+  switch (prop_id)
+    {
+    case PROP_FILE:
+      {
+        GFile *file = g_value_get_object (value);
+        RsvgHandle *handle = rsvg_handle_new_from_gfile_sync (file,
+                                                              RSVG_HANDLE_FLAGS_NONE,
+                                                              NULL,
+                                                              NULL);
+        g_set_object (&self->file, file);
+        g_set_object (&self->handle, handle);
+      }
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+    }
+}
+
+static void
+svg_paintable_get_property (GObject    *object,
+                            guint       prop_id,
+                            GValue     *value,
+                            GParamSpec *pspec)
+{
+  SvgPaintable *self = SVG_PAINTABLE (object);
+
+  switch (prop_id)
+    {
+    case PROP_FILE:
+      g_value_set_object (value, self->file);
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+    }
+}
+
+
+static void
+svg_paintable_class_init (SvgPaintableClass *class)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (class);
+
+  object_class->dispose = svg_paintable_dispose;
+  object_class->set_property = svg_paintable_set_property;
+  object_class->get_property = svg_paintable_get_property;
+
+  g_object_class_install_property (object_class, PROP_FILE,
+                                   g_param_spec_object ("file", "File", "File",
+                                                        G_TYPE_FILE,
+                                                        G_PARAM_READWRITE));
+}
+
+static SvgPaintable *
+svg_paintable_new (GFile *file)
+{
+  return g_object_new (SVG_TYPE_PAINTABLE,
+                       "file", file,
+                       NULL);
+}
+
+static void
+file_set (GtkFileChooserButton *button,
+          GtkWidget            *picture)
+{
+  GFile *file;
+  SvgPaintable *paintable;
+
+  file = gtk_file_chooser_get_file (GTK_FILE_CHOOSER (button));
+
+  paintable = svg_paintable_new (file);
+  gtk_picture_set_paintable (GTK_PICTURE (picture), GDK_PAINTABLE (paintable));
+
+  g_object_unref (paintable);
+  g_object_unref (file);
+}
+
+int
+main (int argc, char *argv[])
+{
+  GtkWidget *window;
+  GtkWidget *header;
+  GtkWidget *picture;
+  GtkFileFilter *filter;
+  GtkWidget *button;
+
+  gtk_init ();
+
+  window = gtk_window_new ();
+  header = gtk_header_bar_new ();
+  gtk_window_set_titlebar (GTK_WINDOW (window), header);
+  button = gtk_file_chooser_button_new ("Select an SVG file", GTK_FILE_CHOOSER_ACTION_OPEN);
+  filter = gtk_file_filter_new ();
+  gtk_file_filter_add_mime_type (filter, "image/svg+xml");
+  gtk_file_chooser_set_filter (GTK_FILE_CHOOSER (button), filter);
+  gtk_header_bar_pack_start (GTK_HEADER_BAR (header), button);
+
+  picture = gtk_picture_new ();
+  g_signal_connect (button, "file-set", G_CALLBACK (file_set), picture);
+
+  gtk_window_set_child (GTK_WINDOW (window), picture);
+
+  gtk_window_present (GTK_WINDOW (window));
+
+  while (g_list_model_get_n_items (gtk_window_get_toplevels ()) > 0)
+    g_main_context_iteration (NULL, TRUE);
+
+  return 0;
+}