Skip to content

formatting: fix incorrect digit grouping #106

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Nov 4, 2025
Merged

formatting: fix incorrect digit grouping #106

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
11 changes: 8 additions & 3 deletions include/frg/formatting.hpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -3,6 +3,7 @@

#include <stdarg.h>
#include <cstddef>
#include <limits.h>
#include <stdint.h>
#include <frg/macros.hpp>
#include <frg/optional.hpp>
Expand Down Expand Up @@ -122,7 +123,7 @@ namespace _fmt_basics {
return;

if (++c == locale_opts.grouping[g]) {
if (locale_opts.grouping[g + 1] > 0)
if (locale_opts.grouping[g + 1] != 0 && locale_opts.grouping[g + 1] != CHAR_MAX)
g++;
else
r++;
Expand Down Expand Up @@ -155,8 +156,11 @@ namespace _fmt_basics {
for (int i = 0; i < precision - k; i++)
step_grouping();

if (!c)
if (!c) {
c = locale_opts.grouping[g];
if (group_thousands)
extra--;
}

if(negative || always_sign || plus_becomes_space)
extra++;
Expand Down Expand Up @@ -187,7 +191,8 @@ namespace _fmt_basics {

for(int i = k - 1; i >= 0; i--) {
sink.append(buffer[i]);
emit_grouping();
if (i)
emit_grouping();
}

if(left_justify && final_width < width)
Expand Down
30 changes: 28 additions & 2 deletions tests/tests.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -319,10 +319,10 @@ TEST(formatting, printf) {
frg::do_printf_chars(*sink_, t, opts, szmod, vsp_);
break;
case 'd': case 'i': case 'o': case 'x': case 'X': case 'b': case 'B': case 'u':
frg::do_printf_ints(*sink_, t, opts, szmod, vsp_);
frg::do_printf_ints(*sink_, t, opts, szmod, vsp_, loc_);
break;
case 'f': case 'F': case 'g': case 'G': case 'e': case 'E': case 'a': case 'A':
frg::do_printf_floats(*sink_, t, opts, szmod, vsp_);
frg::do_printf_floats(*sink_, t, opts, szmod, vsp_, loc_);
break;
default:
// Should not be reached
Expand All @@ -334,6 +334,7 @@ TEST(formatting, printf) {

frg::container_logger<std::string> *sink_;
frg::va_struct *vsp_;
frg::locale_options loc_;
};

auto do_test = [] (const char *expected, const char *format, ...) {
Expand All @@ -354,7 +355,32 @@ TEST(formatting, printf) {
ASSERT_STREQ(expected, buf.data());
};

auto do_test_locale = [] (frg::locale_options loc, const char *expected, const char *format, ...) {
va_list args;
va_start(args, format);

frg::va_struct vs;
frg::arg arg_list[NL_ARGMAX + 1];
vs.arg_list = arg_list;
va_copy(vs.args, args);

std::string buf;
frg::container_logger<std::string> sink{buf};

auto res = frg::printf_format(test_agent{&sink, &vs, loc}, format, &vs);
ASSERT_TRUE(res);

ASSERT_STREQ(expected, buf.data());
};

frg::locale_options en_US{".", ",", "\x3"};
frg::locale_options en_IN{".", ",", "\x3\x2"};

do_test("12", "%d", 12);
do_test_locale(en_US, "123,456,789", "%'d", 123456789);
do_test_locale(en_US, "0000123,456,789", "%'015d", 123456789);
do_test_locale(en_IN, "12,34,56,789", "%'d", 123456789);
do_test_locale(en_IN, "00012,34,56,789", "%'015d", 123456789);

// Test %c right padding.
do_test("a ", "%-2c", 'a');
Expand Down