[gnome-software/1688-reloading-view-upon-install] gs-category-page: Check whether app list was returned, before using it

[Milan Crha <mcrha src gnome org>]

commit cb240fd27999fd9ab9e7bb38bb32012039e2ec87
Author: Milan Crha <mcrha redhat com>
Date:   Mon Aug 22 16:53:36 2022 +0200

    gs-category-page: Check whether app list was returned, before using it
    
    When the load of the category apps had been cancelled or finished with an error,
    the data->app is NULL, which produces a runtime warning when passing it to
    gs_app_list_length().

 src/gs-category-page.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/src/gs-category-page.c b/src/gs-category-page.c
index a254452bc..70364c763 100644
--- a/src/gs-category-page.c
+++ b/src/gs-category-page.c
@@ -221,7 +221,7 @@ choose_top_carousel_apps (LoadCategoryData *data,
        top_carousel_rand = g_rand_new_with_seed (top_carousel_seed);
        g_debug ("Top carousel seed: %u", top_carousel_seed);
 
-       for (guint i = 0; i < gs_app_list_length (data->apps); i++) {
+       for (guint i = 0; data->apps != NULL && i < gs_app_list_length (data->apps); i++) {
                GsApp *app = gs_app_list_index (data->apps, i);
                gboolean is_featured, is_recently_updated, is_hi_res;
 
@@ -299,7 +299,7 @@ load_category_finish (LoadCategoryData *data)
        /* Apps to go in the top carousel */
        top_carousel_apps = choose_top_carousel_apps (data, recently_updated_cutoff_secs);
 
-       for (guint i = 0; i < gs_app_list_length (data->apps); i++) {
+       for (guint i = 0; data->apps != NULL && i < gs_app_list_length (data->apps); i++) {
                GsApp *app = gs_app_list_index (data->apps, i);
                gboolean is_featured, is_recently_updated;
                guint64 release_date;