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Merged
eldakesh-ms merged 7 commits into from
Apr 15, 2021
Merged

chronat: Add year and year_month_day formatting #1840

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<chronat>: Add year and year_month_day formatting
eldakesh-ms Apr 15, 2021
8ec251d
Clang test
eldakesh-ms Apr 15, 2021
84e7c61
Finesse the tests
eldakesh-ms Apr 15, 2021
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review
eldakesh-ms Apr 15, 2021
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eldakesh-ms Apr 15, 2021
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eldakesh-ms Apr 15, 2021
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eldakesh-ms Apr 15, 2021
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184 changes: 166 additions & 18 deletions stl/inc/chrono
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Original file line number Diff line number Diff line change
Expand Up @@ -5408,6 +5408,62 @@ _NODISCARD constexpr const _CharT* _Parse_chrono_format_specs(
}

namespace chrono {
// This echoes the functionality of put_time, but is able to handle invalid dates (when !ok()) since the Standard
// mandates that invalid dates still be formatted properly. For example, put_time isn't able to handle a tm_mday of
// 40, but format("{:%d}", day{40}) should return "40" and operator<< for day prints "40 is not a valid day".
template <class _CharT>
bool _Try_simple_write(basic_ostream<_CharT>& _Os, const char _Type, const tm& _Time) {
const auto _Year = _Time.tm_year + 1900;
const auto _Month = _Time.tm_mon + 1;
switch (_Type) {
case 'd':
case 'e':
if (_Time.tm_mday < 10) {
_Os << (_Type == 'd' ? _CharT{'0'} : _CharT{' '});
}
_Os << _Time.tm_mday;
return true;
case 'm':
if (_Month < 10) {
_Os << _CharT{'0'};
}
_Os << _Month;
return true;
case 'Y':
if (_Year < 0) {
_Os << _CharT{'-'};
}
_Os << _STD format(_STATICALLY_WIDEN(_CharT, "{:04}"), _STD abs(_Year));
return true;
case 'y':
_Os << _STD format(_STATICALLY_WIDEN(_CharT, "{:02}"), _Year < 0 ? 100 + (_Year % 100) : _Year % 100);
return true;
case 'C':
if (_Year < 0) {
_Os << _CharT{'-'};
}
_Os << _STD format(
_STATICALLY_WIDEN(_CharT, "{:02}"), _STD abs(_Time_parse_fields::_Decompose_year(_Year).first) / 100);
return true;
case 'F':
_Try_simple_write(_Os, 'Y', _Time);
_Os << _CharT{'-'};
_Try_simple_write(_Os, 'm', _Time);
_Os << _CharT{'-'};
_Try_simple_write(_Os, 'd', _Time);
return true;
case 'D':
_Try_simple_write(_Os, 'm', _Time);
_Os << _CharT{'/'};
_Try_simple_write(_Os, 'd', _Time);
_Os << _CharT{'/'};
_Try_simple_write(_Os, 'y', _Time);
return true;
default:
return false;
}
}

/*
template <class _CharT, class _Traits, class _Duration>
// clang-format off
Expand All @@ -5431,10 +5487,8 @@ namespace chrono {

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>& operator<<(basic_ostream<_CharT, _Traits>& _Os, const day& _Val) {
if (static_cast<unsigned int>(_Val) < 10) {
_Os << _CharT{'0'};
}
_Os << static_cast<unsigned int>(_Val);
const tm _Time = {.tm_mday = static_cast<int>(static_cast<unsigned int>(_Val))};
_Try_simple_write(_Os, 'd', _Time);
if (!_Val.ok()) {
_Os << _STATICALLY_WIDEN(_CharT, " is not a valid day");
}
Expand All @@ -5451,6 +5505,28 @@ namespace chrono {
}
return _Os << static_cast<unsigned int>(_Val) << _STATICALLY_WIDEN(_CharT, " is not a valid month");
}

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>& operator<<(basic_ostream<_CharT, _Traits>& _Os, const year& _Val) {
const tm _Time = {.tm_year = static_cast<int>(_Val) - 1900};
_Try_simple_write(_Os, 'Y', _Time);
if (!_Val.ok()) {
_Os << _STATICALLY_WIDEN(_CharT, " is not a valid year");
}
return _Os;
}

template <class _CharT, class _Traits>
basic_ostream<_CharT, _Traits>& operator<<(basic_ostream<_CharT, _Traits>& _Os, const year_month_day& _Val) {
const tm _Time = {.tm_mday = static_cast<int>(static_cast<unsigned int>(_Val.day())),
.tm_mon = static_cast<int>(static_cast<unsigned int>(_Val.month())) - 1,
.tm_year = static_cast<int>(_Val.year()) - 1900};
_Try_simple_write(_Os, 'F', _Time);
if (!_Val.ok()) {
_Os << _STATICALLY_WIDEN(_CharT, " is not a valid date");
}
return _Os;
}
} // namespace chrono

/*
Expand All @@ -5472,7 +5548,8 @@ struct formatter<_CHRONO sys_time<_Duration>, _CharT> {

template <class _CharT, bool _Allow_precision>
struct _Chrono_formatter {
auto _Parse(basic_format_parse_context<_CharT>& _Parse_ctx, string_view _Valid_types) {
template <class _Ty>
_NODISCARD auto _Parse(basic_format_parse_context<_CharT>& _Parse_ctx) {
_Chrono_specs_setter<_CharT, basic_format_parse_context<_CharT>> _Callback{_Specs, _Parse_ctx};
const auto _It =
_Parse_chrono_format_specs(_Parse_ctx._Unchecked_begin(), _Parse_ctx._Unchecked_end(), _Callback);
Expand All @@ -5495,7 +5572,7 @@ struct _Chrono_formatter {
}

for (const auto& _Spec : _List) {
if (_Spec._Type != '\0' && _RANGES find(_Valid_types, _Spec._Type) == _Valid_types.end()) {
if (_Spec._Type != '\0' && !_Is_valid_type<_Ty>(_Spec._Type)) {
_THROW(format_error("Invalid type."));
}
_Check_modifier(_Spec._Type, _Spec._Modifier);
Expand All @@ -5516,7 +5593,8 @@ struct _Chrono_formatter {
_Allowed_bit _Allowed;
};

static const _Table_entry _Table[] = {{'d', _O_mod}, {'e', _O_mod}, {'m', _O_mod}};
static const _Table_entry _Table[] = {
{'d', _O_mod}, {'e', _O_mod}, {'m', _O_mod}, {'Y', _E_mod}, {'y', _EO_mod}, {'C', _E_mod}};

const _Allowed_bit _Mod = _Modifier == 'E' ? _E_mod : _O_mod;

Expand All @@ -5529,8 +5607,25 @@ struct _Chrono_formatter {
_THROW(format_error("Incompatible modifier for type"));
}

template <class _Ty>
_NODISCARD constexpr bool _Is_valid_type(const char _Type) noexcept {
if constexpr (is_same_v<_Ty, _CHRONO day>) {
return _Type == 'd' || _Type == 'e';
} else if constexpr (is_same_v<_Ty, _CHRONO month>) {
return _Type == 'b' || _Type == 'B' || _Type == 'h' || _Type == 'm';
} else if constexpr (is_same_v<_Ty, _CHRONO year>) {
return _Type == 'Y' || _Type == 'y' || _Type == 'C';
} else if constexpr (is_same_v<_Ty, _CHRONO year_month_day>) {
return _Type == 'D' || _Type == 'F' || _Is_valid_type<_CHRONO year>(_Type)
|| _Is_valid_type<_CHRONO month>(_Type) || _Is_valid_type<_CHRONO day>(_Type);
Comment on lines +5619 to +5620
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@mnatsuhara mnatsuhara Apr 15, 2021

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I'm wondering if the specifiers that are valid for weekday are also valid here since a specific year, month, and weekday would give us a particular weekday. Similarly, would 'U' and 'V' be valid specifiers since we could get a particular week from a year_month_day?

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@eldakesh-ms eldakesh-ms Apr 15, 2021

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We do not have a weekday. I based which specifiers are legal from put_time, and since it isn't trivial to compute the weekday from just a year/month/day, I think it doesn't apply. I could be very wrong though.

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@eldakesh-ms eldakesh-ms Apr 15, 2021

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After discussing on discord, I agree it makes sense to be able to derive some more information from a year_month_day than I originally implemented.

} else {
// TRANSITION, remove when all types are added
static_assert(_Always_false<_Ty>, "unsupported type");
}
}

template <class _FormatContext, class _Ty>
auto _Write(_FormatContext& _FormatCtx, const _Ty& _Val, const tm& _Time) {
_NODISCARD auto _Write(_FormatContext& _FormatCtx, const _Ty& _Val, const tm& _Time) {
basic_stringstream<_CharT> _Stream;

if (_No_chrono_specs) {
Expand All @@ -5543,10 +5638,12 @@ struct _Chrono_formatter {
continue;
}

// TRANSITION, out of bounds may be legal for non-localized decimal printing, but it isn't very
// consistent.
if (!_Val.ok()) {
_THROW(format_error("Cannot print out-of-bounds time point."));
if (_Type_needs_bounds_checking(_Spec)) {
if (!_Val.ok()) {
_THROW(format_error("Cannot localize out-of-bounds time point."));
}
} else if (_Spec._Modifier == '\0' && _CHRONO _Try_simple_write(_Stream, _Spec._Type, _Time)) {
continue;
}

_CharT _Fmt_str[4];
Expand All @@ -5566,18 +5663,35 @@ struct _Chrono_formatter {
_Fmt_align::_Left, [&](auto _Out) { return _Fmt_write(_STD move(_Out), _Stream.view()); });
}

_NODISCARD bool _Type_needs_bounds_checking(const _Chrono_specs<_CharT>& _Spec) noexcept {
// [tab:time.format.spec]
switch (_Spec._Type) {
case 'a':
case 'A':
case 'b':
case 'B':
case 'h':
case 'z':
case 'Z':
Comment on lines +5669 to +5675
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@mnatsuhara mnatsuhara Apr 15, 2021

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Do you want to just populate this with all of the type specifiers that will end up here? Or were you planning to add to this as we added formatters/operator<<s for each type? I think we'll also need to include %c, %x, %X looking at Table 101.

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@eldakesh-ms eldakesh-ms Apr 15, 2021

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Hmm, I think we need to rename this function. It was conceived as a way to figure out specifiers can throw, so we can explicit about ok() checking. %c uses locale, but I don't think it can ever be out of bounds. Maybe _Type_needs_bounds_checking?

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@mnatsuhara mnatsuhara Apr 15, 2021

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I think %c will actually require more extensive bounds-checking because put_time [says that %c uses all fields of tm so there is even more opportunity for out-of-bounds issues?

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@eldakesh-ms eldakesh-ms Apr 15, 2021

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I want to say that %c is used for a point in time, measured from some base. You can't have an invalid seconds, because you derive the seconds from the amount of time elapsed.

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I'm trying to work out what type would be used to format %c and I think it would probably be time_points right? (e.g., sys_time, etc.). If we would just use time_point::time_since_epoch() then I think you're right.

return true;

default:
return false;
}
}

_Chrono_format_specs<_CharT> _Specs{};
bool _No_chrono_specs = false;
};

template <class _CharT>
struct formatter<_CHRONO day, _CharT> {
typename basic_format_parse_context<_CharT>::iterator parse(basic_format_parse_context<_CharT>& _Parse_ctx) {
return _Impl._Parse(_Parse_ctx, "de");
auto parse(basic_format_parse_context<_CharT>& _Parse_ctx) {
return _Impl.template _Parse<_CHRONO day>(_Parse_ctx);
}

template <class _FormatContext>
typename _FormatContext::iterator format(const _CHRONO day& _Val, _FormatContext& _FormatCtx) {
auto format(const _CHRONO day& _Val, _FormatContext& _FormatCtx) {
const tm _Time = {.tm_mday = static_cast<int>(static_cast<unsigned int>(_Val))};
return _Impl._Write(_FormatCtx, _Val, _Time);
}
Expand All @@ -5588,17 +5702,51 @@ private:

template <class _CharT>
struct formatter<_CHRONO month, _CharT> {
typename basic_format_parse_context<_CharT>::iterator parse(basic_format_parse_context<_CharT>& _Parse_ctx) {
return _Impl._Parse(_Parse_ctx, "bBhm");
auto parse(basic_format_parse_context<_CharT>& _Parse_ctx) {
return _Impl.template _Parse<_CHRONO month>(_Parse_ctx);
}

template <class _FormatContext>
typename _FormatContext::iterator format(const _CHRONO month& _Val, _FormatContext& _FormatCtx) {
auto format(const _CHRONO month& _Val, _FormatContext& _FormatCtx) {
// tm_mon is [0, 11] while month is [1, 12]
const tm _Time = {.tm_mon = static_cast<int>(static_cast<unsigned int>(_Val)) - 1};
return _Impl._Write(_FormatCtx, _Val, _Time);
}

private:
_Chrono_formatter<_CharT, false> _Impl;
};

template <class _CharT>
struct formatter<_CHRONO year, _CharT> {
auto parse(basic_format_parse_context<_CharT>& _Parse_ctx) {
return _Impl.template _Parse<_CHRONO year>(_Parse_ctx);
}

template <class _FormatContext>
auto format(const _CHRONO year& _Val, _FormatContext& _FormatCtx) {
const tm _Time = {.tm_year = static_cast<int>(_Val) - 1900};
return _Impl._Write(_FormatCtx, _Val, _Time);
}

private:
_Chrono_formatter<_CharT, false> _Impl;
};

template <class _CharT>
struct formatter<_CHRONO year_month_day, _CharT> {
auto parse(basic_format_parse_context<_CharT>& _Parse_ctx) {
return _Impl.template _Parse<_CHRONO year_month_day>(_Parse_ctx);
}

template <class _FormatContext>
auto format(const _CHRONO year_month_day& _Val, _FormatContext& _FormatCtx) {
const tm _Time = {.tm_mday = static_cast<int>(static_cast<unsigned int>(_Val.day())),
.tm_mon = static_cast<int>(static_cast<unsigned int>(_Val.month())) - 1,
.tm_year = static_cast<int>(_Val.year()) - 1900};
return _Impl._Write(_FormatCtx, _Val, _Time);
}

private:
_Chrono_formatter<_CharT, false> _Impl;
};
Expand Down
6 changes: 3 additions & 3 deletions tests/libcxx/expected_results.txt
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Original file line number Diff line number Diff line change
Expand Up @@ -283,10 +283,7 @@ std/utilities/time/time.cal/time.cal.mwdlast/time.cal.mwdlast.nonmembers/streami
std/utilities/time/time.cal/time.cal.wdidx/time.cal.wdidx.nonmembers/streaming.pass.cpp FAIL
std/utilities/time/time.cal/time.cal.wdlast/time.cal.wdlast.nonmembers/streaming.pass.cpp FAIL
std/utilities/time/time.cal/time.cal.weekday/time.cal.weekday.nonmembers/streaming.pass.cpp FAIL
std/utilities/time/time.cal/time.cal.year/time.cal.year.nonmembers/streaming.pass.cpp FAIL
std/utilities/time/time.cal/time.cal.ym/time.cal.ym.nonmembers/streaming.pass.cpp FAIL
std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.nonmembers/streaming.pass.cpp FAIL
std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.nonmembers/streaming.pass.cpp FAIL
std/utilities/time/time.cal/time.cal.ymwd/time.cal.ymwd.nonmembers/streaming.pass.cpp FAIL
std/utilities/time/time.cal/time.cal.ymwdlast/time.cal.ymwdlast.nonmembers/streaming.pass.cpp FAIL

Expand Down Expand Up @@ -882,3 +879,6 @@ std/utilities/function.objects/func.search/func.search.bmh/pred.pass.cpp PASS
# Not yet implemented in libcxx and marked as "XFAIL: *"
std/utilities/time/time.cal/time.cal.day/time.cal.day.nonmembers/streaming.pass.cpp SKIPPED
std/utilities/time/time.cal/time.cal.month/time.cal.month.nonmembers/streaming.pass.cpp SKIPPED
std/utilities/time/time.cal/time.cal.year/time.cal.year.nonmembers/streaming.pass.cpp SKIPPED
std/utilities/time/time.cal/time.cal.ymd/time.cal.ymd.nonmembers/streaming.pass.cpp SKIPPED
std/utilities/time/time.cal/time.cal.ymdlast/time.cal.ymdlast.nonmembers/streaming.pass.cpp SKIPPED
3 changes: 0 additions & 3 deletions tests/libcxx/skipped_tests.txt
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Original file line number Diff line number Diff line change
Expand Up @@ -283,10 +283,7 @@ utilities\time\time.cal\time.cal.mwdlast\time.cal.mwdlast.nonmembers\streaming.p
utilities\time\time.cal\time.cal.wdidx\time.cal.wdidx.nonmembers\streaming.pass.cpp
utilities\time\time.cal\time.cal.wdlast\time.cal.wdlast.nonmembers\streaming.pass.cpp
utilities\time\time.cal\time.cal.weekday\time.cal.weekday.nonmembers\streaming.pass.cpp
utilities\time\time.cal\time.cal.year\time.cal.year.nonmembers\streaming.pass.cpp
utilities\time\time.cal\time.cal.ym\time.cal.ym.nonmembers\streaming.pass.cpp
utilities\time\time.cal\time.cal.ymd\time.cal.ymd.nonmembers\streaming.pass.cpp
utilities\time\time.cal\time.cal.ymdlast\time.cal.ymdlast.nonmembers\streaming.pass.cpp
utilities\time\time.cal\time.cal.ymwd\time.cal.ymwd.nonmembers\streaming.pass.cpp
utilities\time\time.cal\time.cal.ymwdlast\time.cal.ymwdlast.nonmembers\streaming.pass.cpp

Expand Down
38 changes: 35 additions & 3 deletions tests/std/tests/P0355R7_calendars_and_time_zones_formatting/test.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -294,7 +294,7 @@ void test_day_formatter() {
assert(res == a8);

assert(format(STR("{:%d %d %d}"), day{27}) == STR("27 27 27"));
throw_helper(STR("{:%d}"), day{200});
assert(format(STR("{:%d}"), day{200}) == STR("200"));
throw_helper(STR("{:%Ed}"), day{10});
assert(format(STR("{}"), day{0}) == STR("00 is not a valid day"));

Expand All @@ -316,10 +316,10 @@ void test_month_formatter() {
assert(format(STR("{:%m %Om}"), month{1}) == STR("01 01"));

// Out of bounds month
throw_helper(STR("{:%m}"), month{0});
assert(format(STR("{:%m}"), month{0}) == STR("00"));
throw_helper(STR("{:%b}"), month{0});
throw_helper(STR("{:%h}"), month{0});
throw_helper(STR("{::%B}"), month{0});
throw_helper(STR("{:%B}"), month{0});

// Invalid specs
throw_helper(STR("{:%A}"), month{1});
Expand All @@ -332,6 +332,32 @@ void test_month_formatter() {
stream_helper(STR("20 is not a valid month"), month{20});
}

template <typename CharT>
void test_year_formatter() {
assert(format(STR("{}"), year{0}) == STR("0000"));
assert(format(STR("{}"), year{-200}) == STR("-0200"));
assert(format(STR("{}"), year{121}) == STR("0121"));

assert(format(STR("{:%Y %y%C}"), year{1912}) == STR("1912 1219"));
assert(format(STR("{:%Y %y%C}"), year{-1912}) == STR("-1912 88-20"));
// TRANSITION, add tests for EY Oy Ey EC

stream_helper(STR("1900"), year{1900});
stream_helper(STR("2000"), year{2000});
stream_helper(STR("-32768 is not a valid year"), year{-32768});
}

template <typename CharT>
void test_year_month_day_formatter() {
year_month_day invalid{year{1234}, month{0}, day{31}};
assert(format(STR("{}"), year_month_day{year{1900}, month{2}, day{1}}) == STR("1900-02-01"));
stream_helper(STR("1900-02-01"), year_month_day{year{1900}, month{2}, day{1}});
stream_helper(STR("1234-00-31 is not a valid date"), invalid);

assert(format(STR("{:%Y %b %d}"), year_month_day{year{1234}, month{5}, day{6}}) == STR("1234 May 06"));
assert(format(STR("{:%F %D}"), invalid) == STR("1234-00-31 00/31/34"));
}

int main() {
test_parse_conversion_spec<char>();
test_parse_conversion_spec<wchar_t>();
Expand All @@ -344,4 +370,10 @@ int main() {

test_month_formatter<char>();
test_month_formatter<wchar_t>();

test_year_formatter<char>();
test_year_formatter<wchar_t>();

test_year_month_day_formatter<char>();
test_year_month_day_formatter<wchar_t>();
}