Run format tests without locale support

Build format-test.cc with FMT_USE_LOCALE=0 in nolocale-test instead of a
separate test file. This replaces two ad-hoc checks with the whole format
test suite. The locale-dependent tests were guarded by the removed
FMT_STATIC_THOUSANDS_SEPARATOR macro, so the guard never took effect.

include/fmt/core.h

@@ -2245,10 +2245,8 @@ template <typename Context> class value {
             FMT_ENABLE_IF(use_formatter<T>::value || !FMT_BUILTIN_TYPES)>
   FMT_CONSTEXPR FMT_INLINE value(T& x) : value(x, custom_tag()) {}
 
-  // Could accept const pointer instead, but this avoids a GCC 16+ false
-  // positive from `-Wmaybe-uninitialized` in Debug builds, in `named_arg_store`
-  // constructor. Related bug report:
-  // https://gcc.gnu.org/bugzilla/show_bug.cgi?id=127470
+  // A non-const pointer avoids a bogus gcc 16 -Wmaybe-uninitialized at -O0 in
+  // named_arg_store: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=127470.
   FMT_ALWAYS_INLINE value(named_arg_info<char_type>* args, size_t size)
       : named_args{args, size} {}
 

include/fmt/format.h

@@ -2793,9 +2793,8 @@ template <typename Char, typename Grouping, typename OutputIt,
 FMT_CONSTEXPR20 auto do_write_float(OutputIt out, const DecimalFP& f,
                                     const format_specs& specs, sign s,
                                     int exp_upper, locale_ref loc) -> OutputIt {
-  Char point = FMT_USE_LOCALE && specs.localized()
-                   ? detail::decimal_point<Char>(loc)
-                   : Char('.');
+  bool localized = FMT_USE_LOCALE && specs.localized();
+  Char point = localized ? detail::decimal_point<Char>(loc) : Char('.');
   int significand_size = get_significand_size(f);
   int exp = f.exponent + significand_size - 1;
   if (specs.type() == presentation_type::fixed ||

test/CMakeLists.txt

@@ -128,11 +128,13 @@ if (FMT_PEDANTIC)
     target_compile_options(noexception-test PRIVATE ${PEDANTIC_COMPILE_FLAGS})
   endif ()
 
-  # Test that the library compiles without locale.
-  add_executable(nolocale-test ../src/format.cc nolocale-test.cc)
+  # Test that the library works without locale support.
+  add_executable(nolocale-test format-test.cc mock-allocator.h ${TEST_MAIN_SRC}
+                               ../src/format.cc ../src/os.cc)
   target_include_directories(nolocale-test
                              PRIVATE ${PROJECT_SOURCE_DIR}/include)
   target_compile_definitions(nolocale-test PRIVATE FMT_USE_LOCALE=0)
+  target_link_libraries(nolocale-test gtest)
   target_compile_options(nolocale-test
                          PRIVATE $<$<CXX_COMPILER_ID:MSVC>:/utf-8>)
   add_test(NAME nolocale-test COMMAND nolocale-test)

test/format-test.cc

@@ -1560,6 +1560,7 @@ TEST(format_test, format_int_locale) {
 TEST(format_test, format_float) {
   EXPECT_EQ(fmt::format("{}", 0.0f), "0");
   EXPECT_EQ(fmt::format("{0:f}", 392.5f), "392.500000");
+  EXPECT_EQ(fmt::format("{:L}", 1234.5), "1234.5");
 }
 
 TEST(format_test, format_double) {
@@ -2250,7 +2251,9 @@ TEST(format_test, fill_via_appender) {
 
 TEST(format_test, formatted_size) {
   EXPECT_EQ(2u, fmt::formatted_size("{}", 42));
+#if FMT_USE_LOCALE
   EXPECT_EQ(2u, fmt::formatted_size(std::locale(), "{}", 42));
+#endif
 }
 
 TEST(format_test, format_to_no_args) {
@@ -2483,7 +2486,9 @@ TEST(format_int_test, format_int) {
             std::to_string(max_value<int64_t>()));
 }
 
-#ifndef FMT_STATIC_THOUSANDS_SEPARATOR
+// This file is also compiled with FMT_USE_LOCALE=0 by nolocale-test, so tests
+// that use std::locale must go in this block.
+#if FMT_USE_LOCALE
 
 #  include <locale>
 
@@ -2548,7 +2553,7 @@ TEST(format_test, format_locale) {
   EXPECT_EQ(fmt::format(loc, "{:10Lo}", 12345), "    30,071");
 }
 
-#endif  // FMT_STATIC_THOUSANDS_SEPARATOR
+#endif  // FMT_USE_LOCALE
 
 struct convertible_to_nonconst_cstring {
   operator char*() const {

test/nolocale-test.cc

@@ -1,13 +0,0 @@
-// Formatting library for C++ - no-locale tests
-//
-// Copyright (c) 2012 - present, Victor Zverovich and {fmt} contributors
-// All rights reserved.
-//
-// For the license information refer to format.h.
-
-#include "fmt/format.h"
-
-int main() {
-  if (fmt::format("{:L}", 1234567) != "1234567") return 1;
-  if (fmt::format("{:L}", 1234.5) != "1234.5") return 1;
-}