Fix T65899, T66314, T61808: various issues appending workspaces

This fixes crashes, wrong names and inability to append workspaces in
edit mode. We now bypass the append operator so we can easily return
a datablock pointer and work in any mode.

2 files changed, 46 insertions, 1 deletions

diff --git a/source/blender/windowmanager/WM_api.h b/source/blender/windowmanager/WM_api.h
index d3c1e5f146d..04e3f7e88dc 100644
--- a/source/blender/windowmanager/WM_api.h
+++ b/source/blender/windowmanager/WM_api.h
@@ -42,6 +42,7 @@ extern "C" {
 struct ARegion;
 struct GHashIterator;
 struct GPUViewport;
+struct ID;
 struct IDProperty;
 struct ImBuf;
 struct ImageFormatData;
@@ -178,6 +179,10 @@ void WM_autosave_init(struct wmWindowManager *wm);
 void WM_recover_last_session(struct bContext *C, struct ReportList *reports);
 void WM_file_tag_modified(void);
 
+struct ID *WM_file_append_datablock(struct bContext *C,
+                                    const char *filepath,
+                                    const short id_code,
+                                    const char *id_name);
 void WM_lib_reload(struct Library *lib, struct bContext *C, struct ReportList *reports);
 
 /* mouse cursors */
diff --git a/source/blender/windowmanager/intern/wm_files_link.c b/source/blender/windowmanager/intern/wm_files_link.c
index 069dc8f441f..5a6606984ba 100644
--- a/source/blender/windowmanager/intern/wm_files_link.c
+++ b/source/blender/windowmanager/intern/wm_files_link.c
@@ -618,10 +618,50 @@ void WM_OT_append(wmOperatorType *ot)
       "Localize all appended data, including those indirectly linked from other libraries");
 }
 
-/** \name Reload/relocate libraries.
+/** \name Append single datablock and return it.
+ *
+ * Used for appending workspace from startup files.
  *
  * \{ */
 
+ID *WM_file_append_datablock(bContext *C,
+                             const char *filepath,
+                             const short id_code,
+                             const char *id_name)
+{
+  Main *bmain = CTX_data_main(C);
+
+  /* Tag everything so we can make local only the new datablock. */
+  BKE_main_id_tag_all(bmain, LIB_TAG_PRE_EXISTING, true);
+
+  /* Define working data, with just the one item we want to append. */
+  WMLinkAppendData *lapp_data = wm_link_append_data_new(0);
+
+  wm_link_append_data_library_add(lapp_data, filepath);
+  WMLinkAppendDataItem *item = wm_link_append_data_item_add(lapp_data, id_name, id_code, NULL);
+  BLI_BITMAP_ENABLE(item->libraries, 0);
+
+  /* Link datablock. */
+  Scene *scene = CTX_data_scene(C);
+  ViewLayer *view_layer = CTX_data_view_layer(C);
+  View3D *v3d = CTX_wm_view3d(C);
+  wm_link_do(lapp_data, NULL, bmain, scene, view_layer, v3d);
+
+  /* Get linked datablock and free working data. */
+  ID *id = item->new_id;
+  wm_link_append_data_free(lapp_data);
+
+  /* Make datablock local. */
+  BKE_library_make_local(bmain, NULL, NULL, true, false);
+
+  /* Clear pre existing tag. */
+  BKE_main_id_tag_all(bmain, LIB_TAG_PRE_EXISTING, false);
+
+  return id;
+}
+
+/** \} */
+
 static int wm_lib_relocate_invoke(bContext *C, wmOperator *op, const wmEvent *UNUSED(event))
 {
   Library *lib;