Relax the requirements for making EditorImportPlugin

doc/classes/EditorImportPlugin.xml

@@ -160,7 +160,7 @@
 			<param index="1" name="option_name" type="StringName" />
 			<param index="2" name="options" type="Dictionary" />
 			<description>
-				This method can be overridden to hide specific import options if conditions are met. This is mainly useful for hiding options that depend on others if one of them is disabled.
+				Gets whether the import option specified by [param option_name] should be visible in the Import dock. The default implementation always returns [code]true[/code], making all options visible. This is mainly useful for hiding options that depend on others if one of them is disabled.
 				[codeblocks]
 				[gdscript]
 				func _get_option_visibility(option, options):
@@ -183,7 +183,6 @@
 				}
 				[/csharp]
 				[/codeblocks]
-				Returns [code]true[/code] to make all options always visible.
 			</description>
 		</method>
 		<method name="_get_preset_count" qualifiers="virtual const">

editor/import/editor_import_plugin.cpp

@@ -66,7 +66,7 @@ String EditorImportPlugin::get_preset_name(int p_idx) const {
 	if (GDVIRTUAL_CALL(_get_preset_name, p_idx, ret)) {
 		return ret;
 	}
-	ERR_FAIL_V_MSG(String(), "Unimplemented _get_preset_name in add-on.");
+	ERR_FAIL_V_MSG(itos(p_idx), "Unimplemented _get_preset_name in add-on.");
 }
 
 int EditorImportPlugin::get_preset_count() const {
@@ -74,7 +74,7 @@ int EditorImportPlugin::get_preset_count() const {
 	if (GDVIRTUAL_CALL(_get_preset_count, ret)) {
 		return ret;
 	}
-	ERR_FAIL_V_MSG(-1, "Unimplemented _get_preset_count in add-on.");
+	return 0;
 }
 
 String EditorImportPlugin::get_save_extension() const {
@@ -98,7 +98,7 @@ float EditorImportPlugin::get_priority() const {
 	if (GDVIRTUAL_CALL(_get_priority, ret)) {
 		return ret;
 	}
-	ERR_FAIL_V_MSG(-1, "Unimplemented _get_priority in add-on.");
+	return 1.0;
 }
 
 int EditorImportPlugin::get_import_order() const {
@@ -106,7 +106,7 @@ int EditorImportPlugin::get_import_order() const {
 	if (GDVIRTUAL_CALL(_get_import_order, ret)) {
 		return ret;
 	}
-	ERR_FAIL_V_MSG(-1, "Unimplemented _get_import_order in add-on.");
+	return IMPORT_ORDER_DEFAULT;
 }
 
 int EditorImportPlugin::get_format_version() const {
@@ -162,8 +162,7 @@ bool EditorImportPlugin::get_option_visibility(const String &p_path, const Strin
 	if (GDVIRTUAL_CALL(_get_option_visibility, p_path, p_option, d, visible)) {
 		return visible;
 	}
-
-	ERR_FAIL_V_MSG(false, "Unimplemented _get_option_visibility in add-on.");
+	return true;
 }
 
 Error EditorImportPlugin::import(ResourceUID::ID p_source_id, const String &p_source_file, const String &p_save_path, const HashMap<StringName, Variant> &p_options, List<String> *r_platform_variants, List<String> *r_gen_files, Variant *r_metadata) {

editor/import_dock.cpp

@@ -379,7 +379,7 @@ void ImportDock::_update_preset_menu() {
 	}
 	preset->show();
 
-	if (params->importer->get_preset_count() == 0) {
+	if (params->importer->get_preset_count() <= 0) {
 		preset->get_popup()->add_item(TTRC("Default"));
 	} else {
 		for (int i = 0; i < params->importer->get_preset_count(); i++) {