testsuite: Add a test that checks for property accessors

Make sure that every object property in GTK has accessors for getting
its value (if the property is readable) or setting it (if it is
writable).

Related: #2440

testsuite/gtk/accessor-apis.c

@@ -0,0 +1,296 @@
+/*
+ * Copyright © 2020 Benjamin Otte
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors: Benjamin Otte <otte@gnome.org>
+ */
+
+#include "config.h"
+
+#include <gtk/gtk.h>
+
+static struct
+{
+  const char *expected;
+  const char *alternative;
+} exceptions[] = {
+  /* keep this sorted please */
+  { "gtk_window_get_display", "gtk_widget_get_display" },
+};
+
+static char *type_exceptions[] = {
+  "GtkCellRenderer",
+  "GtkSettings",
+  "GtkTextTag",
+};
+
+static GModule *module;
+
+static gboolean
+function_exists (const char *function_name)
+{
+  gpointer func;
+  guint i;
+
+  if (g_module_symbol (module, function_name, &func) && func)
+    return TRUE;
+
+  for (i = 0; i < G_N_ELEMENTS(exceptions); i++)
+    {
+      if (g_str_equal (function_name, exceptions[i].expected))
+        {
+          if (exceptions[i].alternative)
+            return function_exists (exceptions[i].alternative);
+          else
+            return TRUE;
+        }
+    }
+
+  return FALSE;
+}
+
+/* Keep in sync with gtkbuilder.c ! */
+static char *
+type_name_mangle (const char *name,
+                  gboolean    split_first_cap)
+{
+  GString *symbol_name = g_string_new ("");
+  gint i;
+
+  for (i = 0; name[i] != '\0'; i++)
+    {
+      /* skip if uppercase, first or previous is uppercase */
+      if ((name[i] == g_ascii_toupper (name[i]) &&
+             ((i > 0 && name[i-1] != g_ascii_toupper (name[i-1])) ||
+              (i == 1 && name[0] == g_ascii_toupper (name[0]) && split_first_cap))) ||
+           (i > 2 && name[i]  == g_ascii_toupper (name[i]) &&
+           name[i-1] == g_ascii_toupper (name[i-1]) &&
+           name[i-2] == g_ascii_toupper (name[i-2])))
+        g_string_append_c (symbol_name, '_');
+      g_string_append_c (symbol_name, g_ascii_tolower (name[i]));
+    }
+
+  return g_string_free (symbol_name, FALSE);
+}
+
+static void
+property_name_mangle (GString    *symbol_name,
+                      const char *name)
+{
+  guint i;
+
+  for (i = 0; name[i] != '\0'; i++)
+    {
+      if (g_ascii_isalnum (name[i]))
+        g_string_append_c (symbol_name, g_ascii_tolower (name[i]));
+      else
+        g_string_append_c (symbol_name, '_');
+    }
+}
+
+const char *getters[] = { "get", "is", "ref" };
+const char *setters[] = { "set" };
+
+static char **
+get_potential_names (GType       type,
+                     gboolean    get,
+                     const char *property_name)
+{
+  GPtrArray *options;
+  char *type_name_options[2];
+  guint n_type_name_options, n_verbs;
+  const char **verbs;
+  guint i, j;
+
+  if (get)
+    {
+      verbs = getters;
+      n_verbs = G_N_ELEMENTS (getters);
+    }
+  else
+    {
+      verbs = setters;
+      n_verbs = G_N_ELEMENTS (setters);
+    }
+
+  type_name_options[0] = type_name_mangle (g_type_name (type), FALSE);
+  type_name_options[1] = type_name_mangle (g_type_name (type), TRUE);
+  if (g_str_equal (type_name_options[0], type_name_options[1]))
+    n_type_name_options = 1;
+  else
+    n_type_name_options = 2;
+
+  options = g_ptr_array_new ();
+
+  for (i = 0; i < n_type_name_options; i++)
+    {
+      for (j = 0; j < n_verbs; j++)
+        {
+          GString *str;
+
+          str = g_string_new (type_name_options[i]);
+          g_string_append_c (str, '_');
+          g_string_append (str, verbs[j]);
+          g_string_append_c (str, '_');
+          property_name_mangle (str, property_name);
+
+          g_ptr_array_add (options, g_string_free (str, FALSE));
+        }
+    }
+
+  g_free (type_name_options[0]);
+  g_free (type_name_options[1]);
+
+  g_ptr_array_add (options, NULL);
+
+  return (char **) g_ptr_array_free (options, FALSE);
+}
+
+static void
+check_function_name (GType       type,
+                     gboolean    get,
+                     const char *property_name)
+{
+  guint i;
+  char **names;
+
+  names = get_potential_names (type, get, property_name);
+
+  for (i = 0; names[i] != NULL; i++)
+    {
+      if (function_exists (names[i]))
+        {
+          g_strfreev (names);
+          return;
+        }
+    }
+
+  g_test_message ("No %s for property %s::%s", get ? "getter" : "setter", g_type_name (type), property_name);
+  for (i = 0; names[i] != NULL; i++)
+    {
+      g_test_message ("    %s", names[i]);
+    }
+
+  g_test_fail ();
+
+  g_strfreev (names);
+}
+
+static void
+check_property (GParamSpec *pspec)
+{
+  if (pspec->flags & G_PARAM_READABLE)
+    {
+      check_function_name (pspec->owner_type,
+                           TRUE,
+                           pspec->name);
+    }
+  if (pspec->flags & G_PARAM_WRITABLE &&
+      !(pspec->flags & G_PARAM_CONSTRUCT_ONLY))
+    {
+      check_function_name (pspec->owner_type,
+                           FALSE,
+                           pspec->name);
+    }
+}
+
+static void
+test_accessors (gconstpointer data)
+{
+  GType type = GPOINTER_TO_SIZE (data);
+  GObjectClass *klass;
+  GParamSpec **pspecs;
+  guint i, n_pspecs;
+
+  klass = g_type_class_ref (type);
+  pspecs = g_object_class_list_properties (klass, &n_pspecs);
+
+  for (i = 0; i < n_pspecs; ++i)
+    {
+      GParamSpec *pspec = pspecs[i];
+
+      if (pspec->owner_type != type)
+	continue;
+
+      check_property (pspec);
+    }
+
+  g_free (pspecs);
+  g_type_class_unref (klass);
+}
+
+static gboolean
+type_is_whitelisted (GType type)
+{
+  guint i;
+
+  if (!G_TYPE_IS_INSTANTIATABLE (type) ||
+      !g_type_is_a (type, G_TYPE_OBJECT))
+    return TRUE;
+
+  for (i = 0; i < G_N_ELEMENTS (type_exceptions); i++)
+    {
+      GType exception = g_type_from_name (type_exceptions[i]);
+
+      /* type hasn't been registered yet */
+      if (exception == G_TYPE_INVALID)
+        continue;
+
+      if (g_type_is_a (type, exception))
+        return TRUE;
+    }
+
+  return FALSE;
+}
+
+int
+main (int argc, char **argv)
+{
+  const GType *all_types;
+  guint n_types = 0, i;
+  gint result;
+
+  /* These must be set before before gtk_test_init */
+  g_setenv ("GIO_USE_VFS", "local", TRUE);
+  g_setenv ("GSETTINGS_BACKEND", "memory", TRUE);
+
+  /* initialize test program */
+  gtk_test_init (&argc, &argv);
+  gtk_test_register_all_types ();
+
+  module = g_module_open (NULL, G_MODULE_BIND_LAZY);
+
+  all_types = gtk_test_list_all_types (&n_types);
+
+  for (i = 0; i < n_types; i++)
+    {
+      char *test_path;
+
+      if (type_is_whitelisted (all_types[i]))
+        continue;
+
+      test_path = g_strdup_printf ("/accessor-apis/%s", g_type_name (all_types[i]));
+
+      g_test_add_data_func (test_path, GSIZE_TO_POINTER (all_types[i]), test_accessors);
+
+      g_free (test_path);
+    }
+
+  result = g_test_run();
+
+  g_module_close (module);
+
+  return result;
+}

testsuite/gtk/meson.build

@@ -10,6 +10,7 @@ endif
 tests = [
   ['accel'],
   ['accessible'],
+  ['accessor-apis'],
   ['action'],
   ['adjustment'],
   ['bitmask', ['../../gtk/gtkallocatedbitmask.c'], ['-DGTK_COMPILATION', '-UG_ENABLE_DEBUG']],