string: add unit test for sprintf

Signed-off-by: Simon Rozman <simon@rozman.si>

UnitTests/UnitTests.vcxproj

@@ -128,6 +128,7 @@
     <ClCompile Include="ring.cpp" />
     <ClCompile Include="sgml.cpp" />
     <ClCompile Include="stream.cpp" />
+    <ClCompile Include="string.cpp" />
     <ClCompile Include="unicode.cpp" />
     <ClCompile Include="watchdog.cpp" />
   </ItemGroup>

UnitTests/UnitTests.vcxproj.filters

@@ -45,6 +45,9 @@
     <ClCompile Include="pool.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
+    <ClCompile Include="string.cpp">
+      <Filter>Source Files</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="pch.hpp">

UnitTests/string.cpp

@@ -0,0 +1,37 @@
+/*
+	SPDX-License-Identifier: MIT
+	Copyright © 2023-2024 Amebis
+*/
+
+#include "pch.hpp"
+
+using namespace std;
+#ifdef _WIN32
+using namespace Microsoft::VisualStudio::CppUnitTestFramework;
+#endif
+
+namespace UnitTests
+{
+	TEST_CLASS(string)
+	{
+	public:
+		TEST_METHOD(sprintf)
+		{
+			Assert::AreEqual(L"This is a test.", stdex::sprintf(L"This is %s.", stdex::locale_default, L"a test").c_str());
+			Assert::AreEqual<size_t>(15, stdex::sprintf(L"This is %s.", stdex::locale_default, L"a test").size());
+			Assert::AreEqual("This is a test.", stdex::sprintf("This is %s.", stdex::locale_default, "a test").c_str());
+			Assert::AreEqual<size_t>(15, stdex::sprintf("This is %s.", stdex::locale_default, "a test").size());
+
+			wstring wstr;
+			std::string str;
+			for (size_t i = 0; i < 2000; i++) {
+				wstr += L"🐔Test🐮\r\n";
+				str += "🐔Test🐮\r\n";
+			}
+			Assert::AreEqual(wstr.c_str(), stdex::sprintf(L"%s", stdex::locale_default, wstr.data()).c_str());
+			Assert::AreEqual(wstr.size(), stdex::sprintf(L"%s", stdex::locale_default, wstr.data()).size());
+			Assert::AreEqual(str.c_str(), stdex::sprintf("%s", stdex::locale_utf8, str.data()).c_str());
+			Assert::AreEqual(str.size(), stdex::sprintf("%s", stdex::locale_utf8, str.data()).size());
+		}
+	};
+}

include/stdex/string.hpp

@@ -2325,7 +2325,6 @@ namespace stdex
 	inline int vsnprintf(_Out_z_cap_(capacity) char* str, _In_ size_t capacity, _In_z_ _Printf_format_string_params_(2) const char* format, _In_opt_ locale_t locale, _In_ va_list arg)
 	{
 #ifdef _WIN32
-		// Don't use _vsnprintf_s(). It terminates the string even if we want to print to the edge of the buffer.
 #pragma warning(suppress: 4996)
 		return _vsnprintf_l(str, capacity, format, locale, arg);
 #else
@@ -2336,7 +2335,6 @@ namespace stdex
 	inline int vsnprintf(_Out_z_cap_(capacity) wchar_t* str, _In_ size_t capacity, _In_z_ _Printf_format_string_params_(2) const wchar_t* format, _In_opt_ locale_t locale, _In_ va_list arg)
 	{
 #ifdef _WIN32
-		// Don't use _vsnwprintf_s(). It terminates the string even if we want to print to the edge of the buffer.
 #pragma warning(suppress: 4996)
 		return _vsnwprintf_l(str, capacity, format, locale, arg);
 #else