Try to resolve some compilation issues around the constexpr string stuff

src/test/http_query.cpp

@@ -23,15 +23,15 @@
 using namespace std::literals;
 
 // Compile-time tests for constexpr on compilers which support C++20 constexpr std::string
-#ifdef __cpp_lib_constexpr_string
+#if defined(__cpp_lib_constexpr_string) && (__GNUC__ >= 12 || _MSC_VER >= 1929)
 constexpr std::string query_constexpr(std::string_view in_expression) {
 	std::string result{ static_cast<std::string>(in_expression) };
 	jessilib::deserialize_http_query(result);
 	return result;
 }
-static_assert(query_constexpr("test"s) == "test"s);
+ASSERT_COMPILES_CONSTEXPR(return query_constexpr("test"s) == "test"s);
-static_assert(query_constexpr("first+second"s) == "first second"s);
+ASSERT_COMPILES_CONSTEXPR(return query_constexpr("first+second"s) == "first second"s);
-static_assert(query_constexpr("first%20second"s) == "first second"s);
+ASSERT_COMPILES_CONSTEXPR(return query_constexpr("first%20second"s) == "first second"s);
 #endif // __cpp_lib_constexpr_string
 
 using char_types = ::testing::Types<char, char8_t, char16_t, char32_t>;

src/test/test.hpp

@@ -1,5 +1,5 @@
 /**
- * Copyright (C) 2018 Jessica James.
+ * Copyright (C) 2018-2021 Jessica James.
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -22,7 +22,11 @@
 #include "gtest/gtest.h"
 
 // Helper macros
+#define ASSERT_COMPILES(expr) static_assert([]() { expr; } != nullptr, "Your compiler is whack yo");
+#define ASSERT_COMPILES_CONSTEXPR(expr) static_assert([]() constexpr { expr; } != nullptr, "Your compiler is whack yo");
 #define UNIQUE_LABEL( LABEL ) LABEL ## __LINE__ ## __
 #define repeat( ITERATIONS ) for (size_t UNIQUE_LABEL(iteration_) = 0; UNIQUE_LABEL(iteration_) != (ITERATIONS); ++ UNIQUE_LABEL(iteration_) )
+#define JESSITEST_CONCAT(lhs, rhs) JESSITEST_CONCAT_HELPER(lhs, rhs)
+#define JESSITEST_CONCAT_HELPER(lhs, rhs) lhs ## rhs
 
 using base_test = ::testing::Test;

src/test/unicode_sequence.cpp

@@ -24,14 +24,14 @@
 using namespace std::literals;
 
 // Compile-time tests for constexpr on compilers which support C++20 constexpr std::string
-#ifdef __cpp_lib_constexpr_string
+#if defined(__cpp_lib_constexpr_string) && (__GNUC__ >= 12 || _MSC_VER >= 1929)
 constexpr std::string cpp_constexpr(std::string_view in_expression) {
 	std::string result{ static_cast<std::string>(in_expression) };
 	jessilib::apply_cpp_escape_sequences(result);
 	return result;
 }
-static_assert(cpp_constexpr("test"s) == "test"s);
+ASSERT_COMPILES_CONSTEXPR(return cpp_constexpr("test"s) == "test"s);
-static_assert(cpp_constexpr("\\r\\n"s) == "\r\n"s);
+ASSERT_COMPILES_CONSTEXPR(return cpp_constexpr("\\r\\n"s) == "\r\n"s);
 #endif // __cpp_lib_constexpr_string
 
 using char_types = ::testing::Types<char, char8_t, char16_t, char32_t>;