diff -r 000000000000 -r cc42fad3fe31 tests/plover-gtk/treemodel.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/tests/plover-gtk/treemodel.c	Tue Jun 29 10:08:33 2021 +0100
@@ -0,0 +1,159 @@
+/*
+ * Copyright (C) 2011, 2016  J. Ali Harlow <ali@juiblex.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include <glib.h>
+#include <gtk/gtk.h>
+
+static void test_tree_model_iter(GtkTreeModel *model,GtkTreeIter *iter)
+{
+    GtkTreePath *path,*path2;
+    GtkTreeIter iter2,child;
+    gchar *string,*string2,*s;
+    int i,n;
+    if (iter)   /* Not all tests make sense on the virtual root */
+    {
+	/* Check we can convert to a path and back */
+	path=gtk_tree_model_get_path(model,iter);
+	g_assert(path!=NULL);
+	g_assert(gtk_tree_model_get_iter(model,&iter2,path));
+	path2=gtk_tree_model_get_path(model,&iter2);
+	g_assert(path2!=NULL);
+	g_assert(gtk_tree_path_compare(path,path2)==0);
+	gtk_tree_path_free(path2);
+	/* Check we can convert to a path string and back */
+	string=gtk_tree_model_get_string_from_iter(model,iter);
+	g_assert(string!=NULL);
+	g_assert(gtk_tree_model_get_iter_from_string(model,&iter2,string));
+	string2=gtk_tree_model_get_string_from_iter(model,&iter2);
+	g_assert(string2!=NULL);
+	g_assert(strcmp(string,string2)==0);
+	g_free(string2);
+    }
+    else
+    {
+	path=NULL;
+	string=NULL;
+    }
+    if (string)
+	g_debug("Checking iter %s",string);
+    else
+	g_debug("Checking virtual root iter");
+    n=gtk_tree_model_iter_n_children(model,iter);
+    g_assert(n>=0);
+    if (n>0)
+    {
+	/* Check that GTK_TREE_MODEL_LIST_ONLY is not set inappropriately */
+	if (iter)
+	{
+	    gboolean list_only_with_grandchildren;
+	    list_only_with_grandchildren=
+	      gtk_tree_model_get_flags(model)&GTK_TREE_MODEL_LIST_ONLY;
+	    g_assert(!list_only_with_grandchildren);
+	}
+	/* Check that gtk_tree_model_iter_has_child() agrees */
+	if (iter)
+	    g_assert(gtk_tree_model_iter_has_child(model,iter));
+	/* Check that gtk_tree_model_iter_children() returns the first child */
+	g_assert(gtk_tree_model_iter_children(model,&child,iter));
+	string2=gtk_tree_model_get_string_from_iter(model,&child);
+	g_assert(string2!=NULL);
+	if (string)
+	{
+	    g_assert(g_str_has_prefix(string2,string));
+	    g_assert(strlen(string2)==strlen(string)+2);
+	    g_assert(g_str_has_suffix(string2,":0"));
+	}
+	else
+	    g_assert(strcmp(string2,"0")==0);
+	g_free(string2);
+	for(i=0;i<n;i++)
+	{
+	    /*
+	     * Check that gtk_tree_model_iter_nth_child() returns the nth child
+	     */
+	    g_assert(gtk_tree_model_iter_nth_child(model,&child,iter,i));
+	    string2=gtk_tree_model_get_string_from_iter(model,&child);
+	    g_assert(string2!=NULL);
+	    if (string)
+		s=g_strdup_printf("%s:%d",string,i);
+	    else
+		s=g_strdup_printf("%d",i);
+	    g_assert(strcmp(string2,s)==0);
+	    g_free(s);
+	    g_free(string2);
+	    /* Check that my son's father is me */
+	    if (iter)
+	    {
+		g_assert(gtk_tree_model_iter_parent(model,&iter2,&child));
+		string2=gtk_tree_model_get_string_from_iter(model,&iter2);
+		g_assert(strcmp(string,string2)==0);
+		g_free(string2);
+	    }
+	    else
+		g_assert(!gtk_tree_model_iter_parent(model,&iter2,&child));
+	    /* Check next sibling */
+	    if (i+1<n)
+	    {
+		iter2=child;
+		g_assert(gtk_tree_model_iter_next(model,&iter2));
+		string2=gtk_tree_model_get_string_from_iter(model,&iter2);
+		g_assert(string2!=NULL);
+		if (string)
+		s=g_strdup_printf("%s:%d",string,i+1);
+		    else
+		s=g_strdup_printf("%d",i+1);
+		g_assert(strcmp(string2,s)==0);
+		g_free(s);
+		g_free(string2);
+	    }
+	    else
+	    {
+		iter2=child;
+		g_assert(!gtk_tree_model_iter_next(model,&iter2));
+	    }
+	    /* Check child */
+	    test_tree_model_iter(model,&child);
+	}
+	/*
+	 * Check that gtk_tree_model_iter_nth_child() returns no more children
+	 */
+	g_assert(!gtk_tree_model_iter_nth_child(model,&child,iter,n));
+    }
+    else
+    {
+	/* Check that all APIs agree that iter has no children */
+	if (iter)
+	    g_assert(!gtk_tree_model_iter_has_child(model,iter));
+	g_assert(!gtk_tree_model_iter_children(model,&child,iter));
+	g_assert(!gtk_tree_model_iter_nth_child(model,&child,iter,0));
+    }
+    gtk_tree_path_free(path);
+    g_free(string);
+}
+
+void test_tree_model(GtkTreeModel *model)
+{
+    GtkTreeModelFlags undefined_flags;
+    undefined_flags=gtk_tree_model_get_flags(model);
+    undefined_flags&=~GTK_TREE_MODEL_ITERS_PERSIST;
+    undefined_flags&=~GTK_TREE_MODEL_LIST_ONLY;
+    g_assert(!undefined_flags);
+    test_tree_model_iter(model,NULL);
+}