fmt/test/custom-formatter-test.cc
2017-01-28 12:51:35 +00:00

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::PrintfArgFormatter;
// A custom argument formatter that doesn't print `-` for floating-point values
// rounded to 0.
class CustomArgFormatter : public fmt::ArgFormatter<char> {
public:
CustomArgFormatter(fmt::writer &w, fmt::basic_format_context<char> &ctx,
fmt::format_specs &s)
: fmt::ArgFormatter<char>(w, ctx, s) {}
using fmt::ArgFormatter<char>::operator();
void operator()(double value) {
if (round(value * pow(10, spec().precision())) == 0)
value = 0;
fmt::ArgFormatter<char>::operator()(value);
}
};
// A custom argument formatter that doesn't print `-` for floating-point values
// rounded to 0.
class CustomPrintfArgFormatter : public PrintfArgFormatter<char> {
public:
CustomPrintfArgFormatter(fmt::basic_writer<char> &w, fmt::format_specs &spec)
: PrintfArgFormatter<char>(w, spec) {}
using PrintfArgFormatter<char>::operator();
void operator()(double value) {
if (round(value * pow(10, spec().precision())) == 0)
value = 0;
PrintfArgFormatter<char>::operator()(value);
}
};
std::string custom_vformat(fmt::CStringRef format_str, fmt::format_args args) {
fmt::MemoryWriter writer;
// Pass custom argument formatter as a template arg to vformat.
fmt::vwrite<CustomArgFormatter>(writer, format_str, args);
return writer.str();
}
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);
}
typedef fmt::printf_context<char, CustomPrintfArgFormatter>
CustomPrintfFormatter;
std::string custom_vsprintf(
const char* format_str,
fmt::basic_format_args<CustomPrintfFormatter> args) {
fmt::MemoryWriter writer;
CustomPrintfFormatter formatter(format_str, args);
formatter.format(writer);
return writer.str();
}
template <typename... Args>
std::string custom_sprintf(const char *format_str, const Args & ... args) {
auto va = fmt::make_xformat_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));
}