[tepl] utils: add list_box_get_filtered_children()

[Sébastien Wilmet <swilmet src gnome org>]

commit c18b4c688923333d03a7a9b16ea272161c150a95
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Wed Nov 4 14:54:50 2020 +0100

    utils: add list_box_get_filtered_children()

 docs/reference/tepl-sections.txt |  1 +
 tepl/tepl-utils.c                | 59 ++++++++++++++++++++++++++++++++++++++++
 tepl/tepl-utils.h                |  6 ++++
 3 files changed, 66 insertions(+)
---
diff --git a/docs/reference/tepl-sections.txt b/docs/reference/tepl-sections.txt
index 5eb93fb..839a1ba 100644
--- a/docs/reference/tepl-sections.txt
+++ b/docs/reference/tepl-sections.txt
@@ -518,6 +518,7 @@ tepl_utils_list_box_setup_scrolling
 tepl_utils_list_box_scroll_to_row
 tepl_utils_list_box_scroll_to_selected_row
 tepl_utils_list_box_get_row_at_index_with_filter
+tepl_utils_list_box_get_filtered_children
 tepl_utils_binding_transform_func_smart_bool
 </SECTION>
 
diff --git a/tepl/tepl-utils.c b/tepl/tepl-utils.c
index ec88c7a..3a949da 100644
--- a/tepl/tepl-utils.c
+++ b/tepl/tepl-utils.c
@@ -952,6 +952,65 @@ tepl_utils_list_box_get_row_at_index_with_filter (GtkListBox           *list_box
        return ret;
 }
 
+/**
+ * tepl_utils_list_box_get_filtered_children:
+ * @list_box: a #GtkListBox.
+ * @filter_func: (scope call): non-%NULL callback function.
+ * @user_data: user data passed to @filter_func.
+ * @n_filtered_children: (out) (optional): location to store the number of
+ *   #GtkListBoxRow's present in the returned array, without counting the
+ *   terminating %NULL.
+ *
+ * Gets an array of all the #GtkListBoxRow childen of @list_box for which
+ * @filter_func returns %TRUE. The elements in the array are sorted by
+ * increasing index order (as returned by gtk_list_box_row_get_index()).
+ *
+ * Returns: (array zero-terminated=1) (element-type GtkListBoxRow) (transfer container) (nullable):
+ *   a %NULL-terminated array of #GtkListBoxRow objects, or %NULL. Free with
+ *   g_free() when no longer needed.
+ * Since: 5.2
+ */
+GtkListBoxRow **
+tepl_utils_list_box_get_filtered_children (GtkListBox           *list_box,
+                                          GtkListBoxFilterFunc  filter_func,
+                                          gpointer              user_data,
+                                          gint                 *n_filtered_children)
+{
+       GPtrArray *filtered_rows;
+       GList *all_rows;
+       GList *l;
+
+       g_return_val_if_fail (GTK_IS_LIST_BOX (list_box), NULL);
+       g_return_val_if_fail (filter_func != NULL, NULL);
+
+       filtered_rows = g_ptr_array_new ();
+       all_rows = gtk_container_get_children (GTK_CONTAINER (list_box));
+
+       for (l = all_rows; l != NULL; l = l->next)
+       {
+               GtkListBoxRow *cur_row = GTK_LIST_BOX_ROW (l->data);
+
+               if (filter_func (cur_row, user_data))
+               {
+                       g_ptr_array_add (filtered_rows, cur_row);
+               }
+       }
+
+       g_list_free (all_rows);
+
+       if (n_filtered_children != NULL)
+       {
+               *n_filtered_children = filtered_rows->len;
+       }
+
+       /* NULL-terminate the array, must be done *after* setting
+        * *n_filtered_children, of course.
+        */
+       g_ptr_array_add (filtered_rows, NULL);
+
+       return (GtkListBoxRow **) g_ptr_array_free (filtered_rows, FALSE);
+}
+
 /**
  * tepl_utils_binding_transform_func_smart_bool:
  * @binding: a #GBinding.
diff --git a/tepl/tepl-utils.h b/tepl/tepl-utils.h
index 68f285b..4c313ee 100644
--- a/tepl/tepl-utils.h
+++ b/tepl/tepl-utils.h
@@ -103,6 +103,12 @@ GtkListBoxRow *    tepl_utils_list_box_get_row_at_index_with_filter (GtkListBox
                                                                  GtkListBoxFilterFunc  filter_func,
                                                                  gpointer              user_data);
 
+_TEPL_EXTERN
+GtkListBoxRow **tepl_utils_list_box_get_filtered_children      (GtkListBox           *list_box,
+                                                                GtkListBoxFilterFunc  filter_func,
+                                                                gpointer              user_data,
+                                                                gint                 *n_filtered_children);
+
 /* Other */
 
 _TEPL_EXTERN