сgen: print generic structs (#6967)

vlib/v/gen/auto_str_methods.v

@@ -367,6 +367,12 @@ fn (mut g Gen) gen_str_for_struct(info table.Struct, styp string, str_fn_name st
 	g.type_definitions.writeln('string indent_${str_fn_name}($styp x, int indent_count); // auto')
 	g.auto_str_funcs.writeln('string indent_${str_fn_name}($styp x, int indent_count) {')
 	mut clean_struct_v_type_name := styp.replace('__', '.')
+	if clean_struct_v_type_name.contains('_T_') {
+		// TODO: this is a bit hacky. styp shouldn't be even parsed with _T_
+		// use something different than g.typ for styp
+		clean_struct_v_type_name = clean_struct_v_type_name.replace('_T_', '<').replace('_', ', ') +
+			'>'
+	}
 	if styp.ends_with('*') {
 		deref_typ := styp.replace('*', '')
 		g.auto_str_funcs.writeln('\t$deref_typ *it = x;')

vlib/v/gen/cgen.v

@@ -500,11 +500,10 @@ static inline $opt_el_type __Option_${styp}_popval($styp ch) {
 fn (g &Gen) cc_type2(t table.Type) string {
 	sym := g.table.get_type_symbol(g.unwrap_generic(t))
 	mut styp := util.no_dots(sym.name)
-	if sym.kind == .struct_ {
-		info := sym.info as table.Struct
-		if info.generic_types.len > 0 {
+	if mut sym.info is table.Struct {
+		if sym.info.generic_types.len > 0 {
 			mut sgtyps := '_T'
-			for gt in info.generic_types {
+			for gt in sym.info.generic_types {
 				gts := g.table.get_type_symbol(if gt.has_flag(.generic) { g.unwrap_generic(gt) } else { gt })
 				sgtyps += '_$gts.name'
 			}

vlib/v/tests/str_gen_test.v

@@ -269,3 +269,24 @@ fn test_alias_struct() {
 	assert t.str() == 'TestAlias($ts)'
 	assert '$t' == 'TestAlias(TestStruct{\n    x: 0\n})'
 }
+
+struct GenericStruct<T> {
+	x T
+}
+
+fn test_generic_struct() {
+	x := GenericStruct<TestStruct>{}
+	assert '$x' == 'GenericStruct<TestStruct>{\n    x: TestStruct{\n        x: 0\n    }\n}'
+	assert x.str() == 'GenericStruct<TestStruct>{\n    x: TestStruct{\n        x: 0\n    }\n}'
+}
+
+struct MultiGenericStruct<T, X> {
+	t T
+	x X
+}
+
+fn test_multi_generic_struct() {
+	x := MultiGenericStruct<TestStruct, TestStruct>{}
+	assert '$x' == 'MultiGenericStruct<TestStruct, TestStruct>{\n    t: TestStruct{\n        x: 0\n    }\n    x: TestStruct{\n        x: 0\n    }\n}'
+	assert x.str() == 'MultiGenericStruct<TestStruct, TestStruct>{\n    t: TestStruct{\n        x: 0\n    }\n    x: TestStruct{\n        x: 0\n    }\n}'
+}