util: Make our stringstream usage locale independent #18432

1153 | @@ -1152,6 +1154,12 @@ TINYFORMAT_FOREACH_ARGNUM(TINYFORMAT_MAKE_FORMAT_FUNCS)
1154 |  template<typename... Args>
1155 |  std::string format(const std::string &fmt, const Args&... args)
1156 |  {
1157 | +    // Numerous tfm::format(...) callers are implicitly assuming that the output
1158 | +    // returned is locale independent. Notable examples include i64tostr, itostr
1159 | +    // and ScriptToAsmStr. Make sure to do a thorough review of all call sites
1160 | +    // (and other direct/indirect stringstream consumers) if this assumption is
1161 | +    // ever removed in the future.
1162 | +    assert(std::locale{} == std::locale::classic());

---

1153 | @@ -1153,6 +1154,7 @@ template<typename... Args>
1154 |  std::string format(const std::string &fmt, const Args&... args)
1155 |  {
1156 |      std::ostringstream oss;
1157 | +    oss.imbue(std::locale::classic());
1158 |      format(oss, fmt.c_str(), args...);
1159 |      return oss.str();

---

 243 | @@ -243,6 +244,7 @@ const std::string& ListBlockFilterTypes()
 244 |      static std::once_flag flag;
 245 |      std::call_once(flag, []() {
 246 |              std::stringstream ret;
 247 | +            ret.imbue(std::locale::classic());

---

   2 | @@ -3,12 +3,12 @@
   3 |  // Distributed under the MIT software license, see the accompanying
   4 |  // file COPYING or http://www.opensource.org/licenses/mit-license.php.
   5 |  
   6 | -#include <wallet/db.h>

---

1130 | @@ -1126,6 +1131,7 @@ template<TINYFORMAT_ARGTYPES(n)>                                          \
1131 |  std::string format(const char* fmt, TINYFORMAT_VARARGS(n))                \
1132 |  {                                                                         \
1133 |      std::ostringstream oss;                                               \
1134 | +    oss.imbue(std::locale::classic()); /* Added for Bitcoin Core */       \

---