Fix reloading preferences ignoring 'script_directory'

Reloading preferences didn't update Python's `sys.path` to account
for the modified `script_directory`.

This meant the operator to load settings from a previous version
required a restart to initialize Python when this directory was set.

1 files changed, 14 insertions, 3 deletions

diff --git a/source/blender/windowmanager/intern/wm_files.c b/source/blender/windowmanager/intern/wm_files.c
index 42d17387d77..090c28a81a6 100644
--- a/source/blender/windowmanager/intern/wm_files.c
+++ b/source/blender/windowmanager/intern/wm_files.c
@@ -580,7 +580,10 @@ static void wm_file_read_post(bContext *C,
 
 #ifdef WITH_PYTHON
   if (is_startup_file) {
-    /* possible python hasn't been initialized */
+    /* On startup (by default), Python won't have been initialized.
+     *
+     * The following block handles data & preferences being reloaded
+     * which requires resetting some internal variables. */
     if (CTX_py_init_get(C)) {
       bool reset_all = use_userdef;
       if (use_userdef || reset_app_template) {
@@ -592,8 +595,16 @@ static void wm_file_read_post(bContext *C,
         }
       }
       if (reset_all) {
-        /* sync addons, these may have changed from the defaults */
-        BPY_run_string_eval(C, (const char *[]){"addon_utils", NULL}, "addon_utils.reset_all()");
+        BPY_run_string_exec(
+            C,
+            (const char *[]){"bpy", "addon_utils", NULL},
+            /* Refresh scripts as the preferences may have changed the user-scripts path.
+             *
+             * This is needed when loading settings from the previous version,
+             * otherwise the script path stored in the preferences would be ignored. */
+            "bpy.utils.refresh_script_paths()\n"
+            /* Sync add-ons, these may have changed from the defaults. */
+            "addon_utils.reset_all()");
       }
       if (use_data) {
         BPY_python_reset(C);