fmt/test/custom-formatter-test.cc
2017-08-13 13:09:02 -07:00

83 lines
2.4 KiB
C++

/*
Custom argument formatter tests
Copyright (c) 2016, Victor Zverovich
All rights reserved.
For the license information refer to format.h.
*/
#include "fmt/printf.h"
#include "gtest-extra.h"
using fmt::printf_arg_formatter;
// A custom argument formatter that doesn't print `-` for floating-point values
// rounded to 0.
class CustomArgFormatter : public fmt::arg_formatter<char> {
public:
CustomArgFormatter(fmt::buffer &buf, fmt::basic_context<char> &ctx,
fmt::format_specs &s)
: fmt::arg_formatter<char>(buf, ctx, s) {}
using fmt::arg_formatter<char>::operator();
void operator()(double value) {
if (round(value * pow(10, spec().precision())) == 0)
value = 0;
fmt::arg_formatter<char>::operator()(value);
}
};
// A custom argument formatter that doesn't print `-` for floating-point values
// rounded to 0.
class CustomPrintfArgFormatter : public printf_arg_formatter<char> {
public:
CustomPrintfArgFormatter(fmt::buffer &buf, fmt::format_specs &spec)
: printf_arg_formatter<char>(buf, spec) {}
using printf_arg_formatter<char>::operator();
void operator()(double value) {
if (round(value * pow(10, spec().precision())) == 0)
value = 0;
printf_arg_formatter<char>::operator()(value);
}
};
std::string custom_vformat(fmt::string_view format_str, fmt::args args) {
fmt::memory_buffer buffer;
// Pass custom argument formatter as a template arg to vwrite.
fmt::vformat_to<CustomArgFormatter>(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_args(args...);
return custom_vformat(format_str, va);
}
typedef fmt::printf_context<char, CustomPrintfArgFormatter>
CustomPrintfFormatter;
std::string custom_vsprintf(
const char* format_str,
fmt::basic_args<CustomPrintfFormatter> args) {
fmt::memory_buffer buffer;
CustomPrintfFormatter formatter(args);
formatter.format(format_str, buffer);
return std::string(buffer.data(), buffer.size());
}
template <typename... Args>
std::string custom_sprintf(const char *format_str, const Args & ... args) {
auto va = fmt::make_args<CustomPrintfFormatter>(args...);
return custom_vsprintf(format_str, va);
}
TEST(CustomFormatterTest, Format) {
EXPECT_EQ("0.00", custom_format("{:.2f}", -.00001));
EXPECT_EQ("0.00", custom_sprintf("%.2f", -.00001));
}