scripts/startup/bl_operators/wm.py

@@ -3501,9 +3501,9 @@ class WM_OT_drop_blend_file(Operator):
 
 class WM_FH_alembic(bpy.types.FileHandler):
     bl_idname = "WM_FH_alembic"
-    bl_label = "alembic"
+    bl_label = "Import Alembic"
     bl_import_operator = "WM_OT_alembic_import"
-    bl_extensions = [{"name": ".abc"}, {"name": ".abc"}, {"name": ".abc"}]
+    bl_file_extensions = [{"extension": ".abc"}]
 
     @classmethod
     def poll(cls, context):
@@ -3512,9 +3512,9 @@ class WM_FH_alembic(bpy.types.FileHandler):
 
 class WM_FH_collada(bpy.types.FileHandler):
     bl_idname = "WM_FH_collada"
-    bl_label = "collada"
+    bl_label = "Import COLLADA"
     bl_import_operator = "WM_OT_collada_import"
-    bl_extensions = [{"name": ".dae"}]
+    bl_file_extensions = [{"extension": ".dae"}]
 
     @classmethod
     def poll(cls, context):
@@ -3523,9 +3523,9 @@ class WM_FH_collada(bpy.types.FileHandler):
 
 class WM_FH_gpencil(bpy.types.FileHandler):
     bl_idname = "WM_FH_gpencil"
-    bl_label = "gpencil"
+    bl_label = "Import gpencil"
     bl_import_operator = "WM_OT_gpencil_import_svg"
-    bl_extensions = [{"name": ".svg"}]
+    bl_file_extensions = [{"extension": ".svg"}]
 
     @classmethod
     def poll(cls, context):
@@ -3534,9 +3534,9 @@ class WM_FH_gpencil(bpy.types.FileHandler):
 
 class WM_FH_obj(bpy.types.FileHandler):
     bl_idname = "WM_FH_obj"
-    bl_label = "obj"
+    bl_label = "Import Wavefront OBJ"
     bl_import_operator = "WM_OT_obj_import"
-    bl_extensions = [{"name": ".obj"}]
+    bl_file_extensions = [{"extension": ".obj"}]
 
     @classmethod
     def poll(cls, context):
@@ -3545,9 +3545,9 @@ class WM_FH_obj(bpy.types.FileHandler):
 
 class WM_FH_ply(bpy.types.FileHandler):
     bl_idname = "WM_FH_ply"
-    bl_label = "ply"
+    bl_label = "Import PLY"
     bl_import_operator = "WM_OT_ply_import"
-    bl_extensions = [{"name": ".ply"}]
+    bl_file_extensions = [{"extension": ".ply"}]
 
     @classmethod
     def poll(cls, context):
@@ -3556,9 +3556,9 @@ class WM_FH_ply(bpy.types.FileHandler):
 
 class WM_FH_stl(bpy.types.FileHandler):
     bl_idname = "WM_FH_stl"
-    bl_label = "stl"
+    bl_label = "Import STL (experimental)"
     bl_import_operator = "WM_OT_stl_import"
-    bl_extensions = [{"name": ".stl"}]
+    bl_file_extensions = [{"extension": ".stl"}]
 
     @classmethod
     def poll(cls, context):
@@ -3567,9 +3567,9 @@ class WM_FH_stl(bpy.types.FileHandler):
 
 class WM_FH_import_mesh_stl(bpy.types.FileHandler):
     bl_idname = "WM_FH_import_mesh_stl"
-    bl_label = "stl"
+    bl_label = "Import STL"
     bl_import_operator = "import_mesh.stl"
-    bl_extensions = [{"name": ".stl"}]
+    bl_file_extensions = [{"extension": ".stl"}]
 
     @classmethod
     def poll(cls, context):
@@ -3578,9 +3578,9 @@ class WM_FH_import_mesh_stl(bpy.types.FileHandler):
 
 class WM_FH_usd(bpy.types.FileHandler):
     bl_idname = "WM_FH_usd"
-    bl_label = "usd"
+    bl_label = "Import USD"
     bl_import_operator = "WM_OT_usd_import"
-    bl_extensions = [{"name": ".usd"}]
+    bl_file_extensions = [{"extension": ".usd"}]
 
     @classmethod
     def poll(cls, context):

source/blender/blenkernel/BKE_screen.h

@@ -668,15 +668,16 @@ struct bFileExtension {
 };
 struct FileHandlerType {
 
-  char idname[BKE_ST_MAXNAME]; /* unique name */
+  char idname[BKE_ST_MAXNAME]; /* Unique name. */
 
-  char label[BKE_ST_MAXNAME]; /* label */
+  char label[BKE_ST_MAXNAME]; /* For UI text. */
 
-  char import_operator[BKE_ST_MAXNAME]; /* import operator name */
+  char import_operator[BKE_ST_MAXNAME]; /* Import operator name, same as #OP_MAX_TYPENAME. */
 
-  /** TODO */
+  /* Check if file handler can be used in a context. */
   bool (*poll)(const struct bContext *C, FileHandlerType *file_handle_type);
 
+  /* List of file extensions supported by the file handler. */
   blender::Vector<bFileExtension> extensions;
 
   /** Equivalent to datablocks ID properties. */

source/blender/editors/io/io_drop_import_helper.cc

@@ -32,10 +32,10 @@ static bool poll_extension(blender::Span<bFileExtension> file_extensions, const
   return false;
 }
 
-static blender::Vector<wmOperatorType *> poll_operators_for_extension(const bContext *C,
-                                                                      const char *extension)
+static blender::Vector<FileHandlerType *> poll_file_handlers_for_extension(bContext *C,
+                                                                           const char *extension)
 {
-  blender::Vector<wmOperatorType *> operators;
+  blender::Vector<FileHandlerType *> result;
   for (auto *file_handler : BKE_file_handlers()) {
     if (!poll_extension(file_handler->extensions, extension)) {
       continue;
@@ -45,11 +45,12 @@ static blender::Vector<wmOperatorType *> poll_operators_for_extension(const bCon
     }
     wmOperatorType *test_operator = WM_operatortype_find(file_handler->import_operator, false);
     if (!test_operator) {
+      /* Discard if import operator does not exist. */
       continue;
     }
-    operators.append(test_operator);
+    result.append(file_handler);
   }
-  return operators;
+  return result;
 }
 
 static PointerRNA copy_file_properties_to_operator_type_pointer(wmOperator *op, wmOperatorType *ot)
@@ -88,13 +89,15 @@ static int wm_drop_import_helper_exec(bContext *C, wmOperator *op)
 {
   char extension[MAX_NAME];
   RNA_string_get(op->ptr, "extension", extension);
-  blender::Vector<wmOperatorType *> operators = poll_operators_for_extension(C, extension);
 
-  if (operators.size() == 0) {
+  blender::Vector<FileHandlerType *> file_handlers = poll_file_handlers_for_extension(C,
+                                                                                      extension);
+
+  if (file_handlers.size() == 0) {
     return OPERATOR_CANCELLED;
   }
 
-  wmOperatorType *ot = operators[0];
+  wmOperatorType *ot = WM_operatortype_find(file_handlers[0]->import_operator, false);
 
   PointerRNA op_props = copy_file_properties_to_operator_type_pointer(op, ot);
 
@@ -108,9 +111,10 @@ static int wm_drop_import_helper_invoke(bContext *C, wmOperator *op, const wmEve
   char extension[MAX_NAME];
   RNA_string_get(op->ptr, "extension", extension);
 
-  blender::Vector<wmOperatorType *> operators = poll_operators_for_extension(C, extension);
+  blender::Vector<FileHandlerType *> file_handlers = poll_file_handlers_for_extension(C,
+                                                                                      extension);
 
-  if (operators.size() <= 1) {
+  if (file_handlers.size() == 1) {
     return wm_drop_import_helper_exec(C, op);
   }
 
@@ -118,11 +122,12 @@ static int wm_drop_import_helper_invoke(bContext *C, wmOperator *op, const wmEve
   uiLayout *layout = UI_popup_menu_layout(pup);
   uiLayoutSetOperatorContext(layout, WM_OP_INVOKE_DEFAULT);
 
-  for (auto *ot : operators) {
+  for (auto *file_handler : file_handlers) {
+    wmOperatorType *ot = WM_operatortype_find(file_handler->import_operator, false);
     PointerRNA op_props = copy_file_properties_to_operator_type_pointer(op, ot);
     uiItemFullO_ptr(layout,
                     ot,
-                    nullptr,
+                    file_handler->label,
                     ICON_NONE,
                     static_cast<IDProperty *>(op_props.data),
                     WM_OP_INVOKE_DEFAULT,
@@ -137,8 +142,8 @@ void WM_OT_drop_import_helper(wmOperatorType *ot)
 {
   ot->name = "Drop Import Herlper";
   ot->description =
-      "Helper operator that handles file drops events and calls operators that can import files "
-      "with extension";
+      "Helper operator that handles file drops and uses file handler information to call "
+      "operators that can import a file with extension.";
   ot->idname = "WM_OT_drop_import_helper";
 
   ot->exec = wm_drop_import_helper_exec;
@@ -187,19 +192,20 @@ static bool poll(bContext *C, wmDrag *drag, const wmEvent * /*event*/)
   const auto paths = WM_drag_get_paths(drag);
   const char *extension = BLI_path_extension(paths[0].c_str());
 
-  return extension && poll_operators_for_extension(C, extension).size() > 0;
+  return extension && poll_file_handlers_for_extension(C, extension).size() > 0;
 }
 static char *tooltip(bContext *C, wmDrag *drag, const int /*xy*/[2], wmDropBox * /*drop*/)
 {
   const auto paths = WM_drag_get_paths(drag);
   const char *extension = BLI_path_extension(paths[0].c_str());
 
-  blender::Vector<wmOperatorType *> operators = poll_operators_for_extension(C, extension);
-  if (operators.size() == 0) {
+  blender::Vector<FileHandlerType *> file_handlers = poll_file_handlers_for_extension(C,
+                                                                                      extension);
+  if (file_handlers.size() == 0) {
     return nullptr;
   }
-  if (operators.size() == 1) {
-    return BLI_strdup(operators[0]->name ? operators[0]->name : operators[0]->idname);
+  if (file_handlers.size() == 1) {
+    return BLI_strdup(file_handlers[0]->label);
   }
 
   return BLI_strdup("Multiple operators can handle this file(s), drop to pick which to use");

source/blender/makesrna/intern/rna_ui.cc

@@ -1371,20 +1371,22 @@ static StructRNA *rna_FileHandler_register(Main *bmain,
   file_handler_type->id_properties = dummy_file_handler_type.id_properties;
   file_handler_type->rna_ext = dummy_file_handler_type.rna_ext;
   memcpy(&file_handler_type->rna_ext, &dummy_file_handler_type.rna_ext, sizeof(ExtensionRNA));
-  int extensions_len = RNA_collection_length(&dummy_file_handler_ptr, "bl_extensions");
-  PropertyRNA *prop = RNA_struct_find_property(&dummy_file_handler_ptr, "bl_extensions");
+
+  /* Load all file extensions defined in the IDProperty. */
+  int extensions_len = RNA_collection_length(&dummy_file_handler_ptr, "bl_file_extensions");
+  PropertyRNA *prop = RNA_struct_find_property(&dummy_file_handler_ptr, "bl_file_extensions");
 
   for (int i = 0; i < extensions_len; i++) {
     PointerRNA fileptr;
     bFileExtension extension;
 
     RNA_property_collection_lookup_int(&dummy_file_handler_ptr, prop, i, &fileptr);
-    RNA_string_get(&fileptr, "name", extension.extension);
-    
+    RNA_string_get(&fileptr, "extension", extension.extension);
+
     file_handler_type->extensions.append(extension);
   }
 
-  RNA_collection_clear(&dummy_file_handler_ptr, "bl_extensions");
+  RNA_collection_clear(&dummy_file_handler_ptr, "bl_file_extensions");
 
   file_handler_type->rna_ext.srna = RNA_def_struct_ptr(
       &BLENDER_RNA, file_handler_type->idname, &RNA_FileHandler);
@@ -2228,7 +2230,7 @@ static void rna_def_file_handler_extensions(BlenderRNA *brna, PropertyRNA *cprop
   RNA_def_property_srna(cprop, "FileExtensions");
   srna = RNA_def_struct(brna, "FileExtensions", nullptr);
   RNA_def_struct_sdna(srna, "bFileExtension");
-  RNA_def_struct_ui_text(srna, "File Extensions", "TODO");
+  RNA_def_struct_ui_text(srna, "File Extensions", "File extensions for file handlers");
 }
 
 static void rna_def_file_handler(BlenderRNA *brna)
@@ -2237,16 +2239,17 @@ static void rna_def_file_handler(BlenderRNA *brna)
   PropertyRNA *prop;
 
   srna = RNA_def_struct(brna, "FileHandler", nullptr);
-  RNA_def_struct_ui_text(srna, "File Handler Type", "TODO");
+  RNA_def_struct_ui_text(srna, "File Handler Type", "I/O File handler");
   RNA_def_struct_sdna(srna, "FileHandler");
   RNA_def_struct_refine_func(srna, "rna_FileHandler_refine");
   RNA_def_struct_idprops_func(srna, "rna_FileHandler_idprops");
   RNA_def_struct_register_funcs(
       srna, "rna_FileHandler_register", "rna_FileHandler_unregister", nullptr);
 
+  RNA_def_struct_translation_context(srna, BLT_I18NCONTEXT_DEFAULT_BPYRNA);
+  RNA_def_struct_flag(srna, STRUCT_PUBLIC_NAMESPACE_INHERIT);
   /* registration */
 
-  RNA_define_verify_sdna(true); /* not in sdna */
   prop = RNA_def_property(srna, "bl_idname", PROP_STRING, PROP_NONE);
   RNA_def_property_string_sdna(prop, nullptr, "type->idname");
   RNA_def_property_flag(prop, PROP_REGISTER);
@@ -2260,24 +2263,28 @@ static void rna_def_file_handler(BlenderRNA *brna)
   prop = RNA_def_property(srna, "bl_import_operator", PROP_STRING, PROP_NONE);
   RNA_def_property_string_sdna(prop, nullptr, "type->import_operator");
   RNA_def_property_flag(prop, PROP_REGISTER);
-  RNA_def_property_ui_text(prop, "Operator", "TODO");
+  RNA_def_property_ui_text(
+      prop,
+      "Operator",
+      "Operator that can handle import files with extension in bl_file_extensions");
 
   prop = RNA_def_property(srna, "bl_label", PROP_STRING, PROP_NONE);
   RNA_def_property_string_sdna(prop, nullptr, "type->label");
   RNA_def_property_flag(prop, PROP_REGISTER);
-  RNA_def_property_ui_text(prop, "Label", "TODO");
+  RNA_def_property_ui_text(prop, "Label", "The file handler label");
 
-  prop = RNA_def_property(srna, "bl_extensions", PROP_COLLECTION, PROP_NONE);
+  prop = RNA_def_property(srna, "bl_file_extensions", PROP_COLLECTION, PROP_NONE);
   RNA_def_property_flag(prop, PROP_REGISTER | PROP_IDPROPERTY);
   RNA_def_property_struct_type(prop, "FileExtension");
-  RNA_def_property_ui_text(prop, "Extensions", "TODO");
+  RNA_def_property_ui_text(prop, "File Extensions", "List of file extensions supported");
   rna_def_file_handler_extensions(brna, prop);
 
   PropertyRNA *parm;
   FunctionRNA *func;
 
   func = RNA_def_function(srna, "poll", nullptr);
-  RNA_def_function_ui_description(func, "TODO");
+  RNA_def_function_ui_description(
+      func, "If this method returns a non-null output, then the file hanlder can be used");
   RNA_def_function_flag(func, FUNC_NO_SELF | FUNC_REGISTER_OPTIONAL);
   RNA_def_function_return(func, RNA_def_boolean(func, "visible", true, "", ""));
   parm = RNA_def_pointer(func, "context", "Context", "", "");
@@ -2391,12 +2398,12 @@ static void rna_def_file_extension(BlenderRNA *brna)
   PropertyRNA *prop;
   srna = RNA_def_struct(brna, "FileExtension", nullptr);
   RNA_def_struct_sdna(srna, "bFileExtension");
-  RNA_def_struct_ui_text(srna, "File Extension", "TODO");
+  RNA_def_struct_ui_text(srna, "File Extension", "File extension for file handlers");
 
-  RNA_define_verify_sdna(false);
-  prop = RNA_def_property(srna, "name", PROP_STRING, PROP_NONE);
+  RNA_define_verify_sdna(false); /* not in sdna */
+  prop = RNA_def_property(srna, "extension", PROP_STRING, PROP_NONE);
   RNA_def_property_string_sdna(prop, nullptr, "extension");
-  RNA_def_property_ui_text(prop, "Extension", "TODO");
+  RNA_def_property_ui_text(prop, "Extension", "File extension");
   RNA_define_verify_sdna(true);
 }
 void RNA_def_ui(BlenderRNA *brna)