add swiftlint rules

.swiftlint.yml

@@ -0,0 +1,59 @@
+---
+whitelist_rules:
+- array_init
+- block_based_kvo
+- closing_brace
+- closure_parameter_position
+- closure_spacing
+- colon
+- comma
+- control_statement
+- custom_rules
+- discarded_notification_center_observer
+- discouraged_direct_init
+- dynamic_inline
+- empty_enum_arguments
+- empty_parameters
+- empty_parentheses_with_trailing_closure
+- explicit_init
+- implicit_getter
+- is_disjoint
+- joined_default_parameter
+- leading_whitespace
+- legacy_cggeometry_functions
+- legacy_constant
+- legacy_constructor
+- legacy_nsgeometry_functions
+- mark
+- multiline_parameters
+- nimble_operator
+- opening_brace
+- operator_usage_whitespace
+- overridden_super_call
+- private_action
+- private_over_fileprivate
+- private_unit_test
+- prohibited_super_call
+- protocol_property_accessors_order
+- quick_discouraged_call
+- quick_discouraged_focused_test
+- quick_discouraged_pending_test
+- redundant_discardable_let
+- redundant_nil_coalescing
+- redundant_string_enum_value
+- redundant_void_return
+- required_enum_case
+- return_arrow_whitespace
+- single_test_class
+- statement_position
+- switch_case_alignment
+- trailing_newline
+- trailing_semicolon
+- unneeded_break_in_switch
+- unused_enumerated
+- unused_optional_binding
+- valid_ibinspectable
+- vertical_whitespace
+- void_return
+- weak_delegate
+- yoda_condition

Sources/XcodeProject/Archiving/PBXPListArchiver.swift

@@ -144,7 +144,7 @@ final class ObjectVisitor {
 	private var objectMap: [PBXGlobalID: PBXObject] = [:]
 	private var visited = Set<PBXGlobalID>()
 
-	func visit(object: PBXObject?, where predicate: @escaping (_ object: PBXObject) -> Bool = { _ in return true}) {
+	func visit(object: PBXObject?, where predicate: @escaping (_ object: PBXObject) -> Bool = { _ in return true }) {
 		guard let object = object else { return }
 		guard !visited.contains(object.globalID) else { return }
 		if predicate(object) {