Make argument formatter customizable

This commit is contained in:
vitaut 2016-03-19 07:20:31 -07:00
parent 9ffe98c00e
commit 52f89065e1
2 changed files with 52 additions and 13 deletions

View File

@ -371,7 +371,13 @@ class BasicWriter;
typedef BasicWriter<char> Writer;
typedef BasicWriter<wchar_t> WWriter;
namespace internal {
template <typename Char>
class BasicArgFormatter;
}
template <typename CharType,
typename ArgFormatter = internal::BasicArgFormatter<CharType> >
class BasicFormatter;
template <typename Char, typename T>
@ -1885,7 +1891,7 @@ class PrintfFormatter : private FormatterBase {
} // namespace internal
/** This template formats data and writes the output to a writer. */
template <typename CharType>
template <typename CharType, typename ArgFormatter>
class BasicFormatter : private internal::FormatterBase {
public:
/** The character type for the output. */
@ -3475,9 +3481,9 @@ void check_sign(const Char *&s, const Arg &arg) {
}
} // namespace internal
template <typename Char>
inline internal::Arg BasicFormatter<Char>::get_arg(
BasicStringRef<Char> arg_name, const char *&error) {
template <typename Char, typename AF>
inline internal::Arg BasicFormatter<Char, AF>::get_arg(
BasicStringRef<Char> arg_name, const char *&error) {
if (check_no_auto_index(error)) {
map_.init(args());
const internal::Arg *arg = map_.find(arg_name);
@ -3488,8 +3494,8 @@ inline internal::Arg BasicFormatter<Char>::get_arg(
return internal::Arg();
}
template <typename Char>
inline internal::Arg BasicFormatter<Char>::parse_arg_index(const Char *&s) {
template <typename Char, typename AF>
inline internal::Arg BasicFormatter<Char, AF>::parse_arg_index(const Char *&s) {
const char *error = 0;
internal::Arg arg = *s < '0' || *s > '9' ?
next_arg(error) : get_arg(internal::parse_nonnegative_int(s), error);
@ -3500,8 +3506,8 @@ inline internal::Arg BasicFormatter<Char>::parse_arg_index(const Char *&s) {
return arg;
}
template <typename Char>
inline internal::Arg BasicFormatter<Char>::parse_arg_name(const Char *&s) {
template <typename Char, typename AF>
inline internal::Arg BasicFormatter<Char, AF>::parse_arg_name(const Char *&s) {
assert(internal::is_name_start(*s));
const Char *start = s;
Char c;
@ -3515,8 +3521,8 @@ inline internal::Arg BasicFormatter<Char>::parse_arg_name(const Char *&s) {
return arg;
}
template <typename Char>
const Char *BasicFormatter<Char>::format(
template <typename Char, typename ArgFormatter>
const Char *BasicFormatter<Char, ArgFormatter>::format(
const Char *&format_str, const internal::Arg &arg) {
using internal::Arg;
const Char *s = format_str;
@ -3681,12 +3687,12 @@ const Char *BasicFormatter<Char>::format(
FMT_THROW(FormatError("missing '}' in format string"));
// Format argument.
internal::BasicArgFormatter<Char>(*this, spec, s - 1).visit(arg);
ArgFormatter(*this, spec, s - 1).visit(arg);
return s;
}
template <typename Char>
void BasicFormatter<Char>::format(BasicCStringRef<Char> format_str) {
template <typename Char, typename AF>
void BasicFormatter<Char, AF>::format(BasicCStringRef<Char> format_str) {
const Char *s = format_str.c_str();
const Char *start = s;
while (*s) {

View File

@ -1658,3 +1658,36 @@ std::ostream &operator<<(std::ostream &os, EmptyTest) {
TEST(FormatTest, EmptyCustomOutput) {
EXPECT_EQ("", fmt::format("{}", EmptyTest()));
}
class CustomArgFormatter :
public fmt::internal::ArgFormatterBase<CustomArgFormatter, char> {
public:
typedef fmt::internal::ArgFormatterBase<CustomArgFormatter, char> Base;
CustomArgFormatter(fmt::BasicFormatter<char, CustomArgFormatter> &f,
fmt::FormatSpec &s, const char *)
: fmt::internal::ArgFormatterBase<CustomArgFormatter, char>(f.writer(), s) {
}
void visit_int(int value) {
fmt::FormatSpec &spec = this->spec();
if (spec.type() == 'x')
visit_uint(value); // convert to unsigned and format
else
Base::visit_int(value);
}
};
std::string custom_format(const char *format_str, fmt::ArgList args) {
fmt::MemoryWriter writer;
fmt::BasicFormatter<char, CustomArgFormatter> formatter(args, writer);
formatter.format(format_str);
return writer.str();
}
FMT_VARIADIC(std::string, custom_format, const char *)
TEST(FormatTest, CustomArgFormatter) {
int x = -0xbeef;
EXPECT_EQ(fmt::format("{:x}", static_cast<unsigned>(x)),
custom_format("{:x}", x));
}