checker: require `params` attribute to use struct as keyword arguments in function (#11135)

vlib/gx/text.v

@@ -1,11 +1,12 @@
 module gx
 
-// TODO: remove these and uae the enum everywhere
+// TODO: remove these, and use the enum everywhere
 pub const (
 	align_left  = HorizontalAlign.left
 	align_right = HorizontalAlign.right
 )
 
+[params]
 pub struct TextCfg {
 pub:
 	color          Color = black

vlib/io/util/util.v

@@ -8,6 +8,7 @@ const (
 	retries = 10000
 )
 
+[params]
 pub struct TempFileOptions {
 	path    string = os.temp_dir()
 	pattern string
@@ -44,6 +45,7 @@ pub fn temp_file(tfo TempFileOptions) ?(os.File, string) {
 		' could not create temporary file in "$d". Retry limit ($util.retries) exhausted. Please ensure write permissions.')
 }
 
+[params]
 pub struct TempDirOptions {
 	path    string = os.temp_dir()
 	pattern string

vlib/math/big/integer.v

@@ -97,6 +97,7 @@ pub fn integer_from_u64(value u64) Integer {
 	}
 }
 
+[params]
 pub struct IntegerConfig {
 	signum int = 1
 }

vlib/net/http/header.v

@@ -533,6 +533,7 @@ pub fn (h Header) keys() []string {
 	return h.data.keys()
 }
 
+[params]
 pub struct HeaderRenderConfig {
 	version      Version
 	coerce       bool

vlib/rand/config/config.v

@@ -7,6 +7,7 @@ import rand.seed
 // generator WyRand used 64 bits, ie. 2 u32s so that is the default. In case your desired generator
 // uses a different number of u32s, use the `seed.time_seed_array()` method with the correct
 // number of u32s.
+[params]
 pub struct PRNGConfigStruct {
 pub:
 	seed_ []u32 = seed.time_seed_array(2)

vlib/time/stopwatch.v

@@ -3,6 +3,7 @@
 // that can be found in the LICENSE file.
 module time
 
+[params]
 pub struct StopWatchOptions {
 	auto_start bool = true
 }

vlib/v/ast/table.v

@@ -352,6 +352,7 @@ pub fn (t &Table) type_find_method(s &TypeSymbol, name string) ?Fn {
 	return none
 }
 
+[params]
 pub struct GetEmbedsOptions {
 	preceding []Type
 }

vlib/v/checker/checker.v

@@ -2088,15 +2088,17 @@ pub fn (mut c Checker) check_expected_arg_count(mut node ast.CallExpr, f &ast.Fn
 		if min_required_params == nr_args + 1 {
 			last_typ := f.params.last().typ
 			last_sym := c.table.get_type_symbol(last_typ)
-			if last_sym.kind == .struct_ {
-				// allow empty trailing struct syntax arg (`f()` where `f` is `fn(ConfigStruct)`)
-				node.args << ast.CallArg{
-					expr: ast.StructInit{
-						typ: last_typ
+			if last_sym.info is ast.Struct {
+				is_params := last_sym.info.attrs.filter(it.name == 'params' && !it.has_arg).len > 0
+				if is_params {
+					// allow empty trailing struct syntax arg (`f()` where `f` is `fn(ConfigStruct)`)
+					node.args << ast.CallArg{
+						expr: ast.StructInit{
+							typ: last_typ
+						}
 					}
-					typ: last_typ
+					return
 				}
-				return
 			}
 		}
 		c.error('expected $min_required_params arguments, but got $nr_args', node.pos)

vlib/v/fmt/align.v

@@ -14,6 +14,7 @@ mut:
 	max_type_len int
 }
 
+[params]
 struct AddInfoConfig {
 	use_threshold bool
 }

vlib/v/fmt/attrs.v

@@ -18,6 +18,7 @@ pub fn (mut f Fmt) attrs(attrs []ast.Attr) {
 	}
 }
 
+[params]
 pub struct AttrsOptions {
 	inline bool
 }

vlib/v/fmt/comments.v

@@ -16,6 +16,7 @@ pub enum CommentsLevel {
 // - level:  either .keep (don't indent), or .indent (increment indentation)
 // - iembed: a /* ... */ block comment used inside expressions; // comments the whole line
 // - prev_line: the line number of the previous token to save linebreaks
+[params]
 pub struct CommentsOptions {
 	has_nl    bool = true
 	inline    bool

vlib/v/fmt/fmt.v

@@ -133,6 +133,7 @@ pub fn (mut f Fmt) wrap_long_line(penalty_idx int, add_indent bool) bool {
 	return true
 }
 
+[params]
 pub struct RemoveNewLineConfig {
 	imports_buffer bool // Work on f.out_imports instead of f.out
 }

vlib/v/parser/parser.v

@@ -642,6 +642,7 @@ pub fn (mut p Parser) comment_stmt() ast.ExprStmt {
 	}
 }
 
+[params]
 struct EatCommentsConfig {
 	same_line bool // Only eat comments on the same line as the previous token
 	follow_up bool // Comments directly below the previous token as long as there is no empty line

vlib/v/tests/match_in_fn_call_test.v

@@ -1,3 +1,4 @@
+[params]
 struct Data {
 	array []int
 }

vlib/v/tests/missing_config_struct_arg_test.v

@@ -1,3 +1,4 @@
+[params]
 struct Foo {
 	x int
 }
@@ -6,6 +7,7 @@ fn foo(f Foo) int {
 	return f.x
 }
 
+[params]
 struct Bar {
 	x int
 	y int = 1234

vlib/v/tests/struct_test.v

@@ -247,6 +247,7 @@ fn test_fixed_field() {
 	//}
 }
 */
+[params]
 struct Config {
 mut:
 	n   int