tree faa9bba7eb6fcc46d22842ea467fca97431076b2
parent 7e1af334ee9c85a930070393184aa2806af8a94c
author Javid Khan <dxbjavid@gmail.com> 1783663444 -0700
committer Copybara-Service <copybara-worker@google.com> 1783663526 -0700

PR #2093: reject unpaired surrogates when formatting wide strings

Imported from GitHub PR https://github.com/abseil/abseil-cpp/pull/2093

**partial utf-8 emitted for unpaired surrogates in wide-string formatting**

When a wide string passed to %ls (or a std::wstring) contains a high surrogate with no following low surrogate, ConvertStringArg keeps the two bytes WideToUtf8 writes for the first half of the pair and still reports success, so the formatted output carries a truncated utf-8 sequence. The single wchar_t path already rejects an unpaired surrogate via saw_high_surrogate, so this just brings the string path in line with it and adds a convert_test case for the trailing, mid-string and lone-low variants.
Merge da58a96d88c5d6ddfeb014f14da47b8965de9cca into 0d1af721b72710afc6d50e880cc111eb852e4e22

Merging this change closes #2093

COPYBARA_INTEGRATE_REVIEW=https://github.com/abseil/abseil-cpp/pull/2093 from dxbjavid:wide-format-unpaired-surrogate da58a96d88c5d6ddfeb014f14da47b8965de9cca
PiperOrigin-RevId: 945509522
Change-Id: Ifc1cdde9dc5c3850f5a01205c27ab97bda84e729