cgen: fix error for print comptime for method call (#13108)

vlib/v/gen/c/fn.v

@@ -869,6 +869,15 @@ fn (mut g Gen) method_call(node ast.CallExpr) {
 					return
 				}
 			}
+		} else if node.left is ast.ComptimeCall {
+			if node.left.method_name == 'method' {
+				sym := g.table.sym(g.unwrap_generic(node.left.left_type))
+				if m := sym.find_method(g.comptime_for_method) {
+					rec_type = m.return_type
+					g.gen_expr_to_string(node.left, rec_type)
+					return
+				}
+			}
 		} else if node.left is ast.Ident {
 			if node.left.obj is ast.Var {
 				if g.comptime_var_type_map.len > 0 {
@@ -1219,6 +1228,13 @@ fn (mut g Gen) fn_call(node ast.CallExpr) {
 							typ = g.comptime_var_type_map[key_str] or { typ }
 						}
 					}
+				} else if expr is ast.ComptimeCall {
+					if expr.method_name == 'method' {
+						sym := g.table.sym(g.unwrap_generic(expr.left_type))
+						if m := sym.find_method(g.comptime_for_method) {
+							typ = m.return_type
+						}
+					}
 				} else if expr is ast.Ident {
 					if expr.obj is ast.Var {
 						typ = expr.obj.typ

vlib/v/tests/comptime_for_method_call_in_print_call_test.v

@@ -0,0 +1,34 @@
+module main
+
+struct S1 {}
+
+fn test_comptime_for_method_call_str() {
+	s1 := S1{}
+	mut rets := []string{}
+
+	$for method in S1.methods {
+		println(s1.$method('ll'))
+		rets << s1.$method('ll').str()
+	}
+	assert rets.len == 4
+	assert rets[0] == '7'
+	assert rets[1] == '7.7'
+	assert rets[2] == 'foo'
+	assert rets[3] == 'true'
+}
+
+fn (t S1) m1(s string) int {
+	return 7
+}
+
+fn (t S1) m2(s string) f64 {
+	return 7.7
+}
+
+fn (t S1) m3(s string) string {
+	return 'foo'
+}
+
+fn (t S1) m4(s string) bool {
+	return true
+}