fmt/test/custom-formatter-test.cc

57 lines
1.6 KiB
C++

// Formatting library for C++ - custom argument formatter tests
//
// Copyright (c) 2012 - present, Victor Zverovich
// All rights reserved.
//
// For the license information refer to format.h.
#ifndef _CRT_SECURE_NO_WARNINGS
#define _CRT_SECURE_NO_WARNINGS
#endif
#include "fmt/format.h"
#include "gtest-extra.h"
// MSVC 2013 is known to be broken.
#if !FMT_MSC_VER || FMT_MSC_VER > 1800
// A custom argument formatter that doesn't print `-` for floating-point values
// rounded to 0.
class custom_arg_formatter
: public fmt::arg_formatter<fmt::buffer_range<char>> {
public:
using range = fmt::buffer_range<char>;
typedef fmt::arg_formatter<range> base;
custom_arg_formatter(fmt::format_context& ctx,
fmt::format_parse_context* parse_ctx,
fmt::format_specs* s = nullptr)
: base(ctx, parse_ctx, s) {}
using base::operator();
iterator operator()(double value) {
// Comparing a float to 0.0 is safe.
if (round(value * pow(10, specs()->precision)) == 0.0) value = 0;
return base::operator()(value);
}
};
std::string custom_vformat(fmt::string_view format_str, fmt::format_args args) {
fmt::memory_buffer buffer;
// Pass custom argument formatter as a template arg to vwrite.
fmt::vformat_to<custom_arg_formatter>(buffer, format_str, args);
return std::string(buffer.data(), buffer.size());
}
template <typename... Args>
std::string custom_format(const char* format_str, const Args&... args) {
auto va = fmt::make_format_args(args...);
return custom_vformat(format_str, va);
}
TEST(CustomFormatterTest, Format) {
EXPECT_EQ("0.00", custom_format("{:.2f}", -.00001));
}
#endif