Source/JavaScriptCore/runtime/IntlRelativeTimeFormat.cpp - WebKit - Git at Google

 /*
  * Copyright (C) 2020 Sony Interactive Entertainment Inc.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
  * THE POSSIBILITY OF SUCH DAMAGE.
  */

 #include "config.h"
 #include "IntlRelativeTimeFormat.h"

 #include "Error.h"
 #include "IntlNumberFormat.h"
 #include "IntlObject.h"
 #include "JSGlobalObjectInlines.h"
 #include "ObjectConstructor.h"
 #include <wtf/unicode/icu/ICUHelpers.h>

 namespace JSC {

 const ClassInfo IntlRelativeTimeFormat::s_info = { "Object", &Base::s_info, nullptr, nullptr, CREATE_METHOD_TABLE(IntlRelativeTimeFormat) };

 namespace IntlRelativeTimeFormatInternal {
 constexpr const char* relevantExtensionKeys[1] = { "nu" };
 }

 void IntlRelativeTimeFormat::URelativeDateTimeFormatterDeleter::operator()(URelativeDateTimeFormatter* relativeDateTimeFormatter) const
 {
     if (relativeDateTimeFormatter)
         ureldatefmt_close(relativeDateTimeFormatter);
 }

 void IntlRelativeTimeFormat::UNumberFormatDeleter::operator()(UNumberFormat* numberFormat) const
 {
     if (numberFormat)
         unum_close(numberFormat);
 }

 IntlRelativeTimeFormat* IntlRelativeTimeFormat::create(VM& vm, Structure* structure)
 {
     auto* format = new (NotNull, allocateCell<IntlRelativeTimeFormat>(vm.heap)) IntlRelativeTimeFormat(vm, structure);
     format->finishCreation(vm);
     return format;
 }

 Structure* IntlRelativeTimeFormat::createStructure(VM& vm, JSGlobalObject* globalObject, JSValue prototype)
 {
     return Structure::create(vm, globalObject, prototype, TypeInfo(ObjectType, StructureFlags), info());
 }

 IntlRelativeTimeFormat::IntlRelativeTimeFormat(VM& vm, Structure* structure)
     : Base(vm, structure)
 {
 }

 void IntlRelativeTimeFormat::finishCreation(VM& vm)
 {
     Base::finishCreation(vm);
     ASSERT(inherits(vm, info()));
 }

 void IntlRelativeTimeFormat::visitChildren(JSCell* cell, SlotVisitor& visitor)
 {
     auto* thisObject = jsCast<IntlRelativeTimeFormat*>(cell);
     ASSERT_GC_OBJECT_INHERITS(thisObject, info());

     Base::visitChildren(thisObject, visitor);
 }

 Vector<String> IntlRelativeTimeFormat::localeData(const String& locale, size_t keyIndex)
 {
     // The index of the extension key "nu" in relevantExtensionKeys is 0.
     ASSERT_UNUSED(keyIndex, !keyIndex);
     return numberingSystemsForLocale(locale);
 }

 // https://tc39.es/ecma402/#sec-InitializeRelativeTimeFormat
 void IntlRelativeTimeFormat::initializeRelativeTimeFormat(JSGlobalObject* globalObject, JSValue locales, JSValue optionsValue)
 {
     VM& vm = globalObject->vm();
     auto scope = DECLARE_THROW_SCOPE(vm);

     Vector<String> requestedLocales = canonicalizeLocaleList(globalObject, locales);
     RETURN_IF_EXCEPTION(scope, void());

     JSObject* options;
     if (optionsValue.isUndefined())
         options = constructEmptyObject(vm, globalObject->nullPrototypeObjectStructure());
     else {
         options = optionsValue.toObject(globalObject);
         RETURN_IF_EXCEPTION(scope, void());
     }

     HashMap<String, String> opt;
     String localeMatcher = intlStringOption(globalObject, options, vm.propertyNames->localeMatcher, { "lookup", "best fit" }, "localeMatcher must be either \"lookup\" or \"best fit\"", "best fit");
     RETURN_IF_EXCEPTION(scope, void());
     opt.add(vm.propertyNames->localeMatcher.string(), localeMatcher);

     String numberingSystem = intlStringOption(globalObject, options, vm.propertyNames->numberingSystem, { }, nullptr, nullptr);
     RETURN_IF_EXCEPTION(scope, void());
     if (!numberingSystem.isNull()) {
         if (!isUnicodeLocaleIdentifierType(numberingSystem)) {
             throwRangeError(globalObject, scope, "numberingSystem is not a well-formed numbering system value"_s);
             return;
         }
         opt.add("nu"_s, numberingSystem);
     }

     const HashSet<String>& availableLocales = intlRelativeTimeFormatAvailableLocales();
     HashMap<String, String> resolved = resolveLocale(globalObject, availableLocales, requestedLocales, opt, IntlRelativeTimeFormatInternal::relevantExtensionKeys, WTF_ARRAY_LENGTH(IntlRelativeTimeFormatInternal::relevantExtensionKeys), localeData);
     m_locale = resolved.get(vm.propertyNames->locale.string());
     if (m_locale.isEmpty()) {
         throwTypeError(globalObject, scope, "failed to initialize RelativeTimeFormat due to invalid locale"_s);
         return;
     }

     m_numberingSystem = resolved.get("nu"_s);
     CString dataLocaleWithExtensions = makeString(resolved.get("dataLocale"_s), "-u-nu-", m_numberingSystem).utf8();

     String style = intlStringOption(globalObject, options, vm.propertyNames->style, { "long", "short", "narrow" }, "style must be either \"long\", \"short\", or \"narrow\"", "long");
     RETURN_IF_EXCEPTION(scope, void());
     if (style == "long")
         m_style = UDAT_STYLE_LONG;
     else if (style == "short")
         m_style = UDAT_STYLE_SHORT;
     else if (style == "narrow")
         m_style = UDAT_STYLE_NARROW;
     else
         ASSERT_NOT_REACHED();

     String numeric = intlStringOption(globalObject, options, vm.propertyNames->numeric, { "always", "auto" }, "numeric must be either \"always\" or \"auto\"", "always");
     RETURN_IF_EXCEPTION(scope, void());
     m_numeric = (numeric == "always");

     UErrorCode status = U_ZERO_ERROR;
     m_numberFormat = std::unique_ptr<UNumberFormat, UNumberFormatDeleter>(unum_open(UNUM_DECIMAL, nullptr, 0, dataLocaleWithExtensions.data(), nullptr, &status));
     if (UNLIKELY(U_FAILURE(status))) {
         throwTypeError(globalObject, scope, "failed to initialize RelativeTimeFormat"_s);
         return;
     }

     m_relativeDateTimeFormatter = std::unique_ptr<URelativeDateTimeFormatter, URelativeDateTimeFormatterDeleter>(ureldatefmt_open(dataLocaleWithExtensions.data(), m_numberFormat.get(), m_style, UDISPCTX_CAPITALIZATION_FOR_STANDALONE, &status));
     if (UNLIKELY(U_FAILURE(status))) {
         throwTypeError(globalObject, scope, "failed to initialize RelativeTimeFormat"_s);
         return;
     }
 }

 static ASCIILiteral styleString(UDateRelativeDateTimeFormatterStyle style)
 {
     switch (style) {
     case UDAT_STYLE_LONG:
         return "long"_s;
     case UDAT_STYLE_SHORT:
         return "short"_s;
     case UDAT_STYLE_NARROW:
         return "narrow"_s;
     }
     ASSERT_NOT_REACHED();
     return ASCIILiteral::null();
 }

 static ASCIILiteral numericString(bool numeric)
 {
     return numeric ? "always"_s : "auto"_s;
 }

 // https://tc39.es/ecma402/#sec-intl.relativetimeformat.prototype.resolvedoptions
 JSObject* IntlRelativeTimeFormat::resolvedOptions(JSGlobalObject* globalObject) const
 {
     VM& vm = globalObject->vm();
     JSObject* options = constructEmptyObject(globalObject);
     options->putDirect(vm, vm.propertyNames->locale, jsNontrivialString(vm, m_locale));
     options->putDirect(vm, vm.propertyNames->style, jsNontrivialString(vm, styleString(m_style)));
     options->putDirect(vm, vm.propertyNames->numeric, jsNontrivialString(vm, numericString(m_numeric)));
     options->putDirect(vm, vm.propertyNames->numberingSystem, jsNontrivialString(vm, m_numberingSystem));
     return options;
 }

 static StringView singularUnit(StringView unit)
 {
     // Plurals are allowed, but thankfully they're all just a simple -s.
     return unit.endsWith("s") ? unit.left(unit.length() - 1) : unit;
 }

 // https://tc39.es/ecma402/#sec-singularrelativetimeunit
 static Optional<URelativeDateTimeUnit> relativeTimeUnitType(StringView unit)
 {
     StringView singular = singularUnit(unit);

     if (singular == "second")
         return UDAT_REL_UNIT_SECOND;
     if (singular == "minute")
         return UDAT_REL_UNIT_MINUTE;
     if (singular == "hour")
         return UDAT_REL_UNIT_HOUR;
     if (singular == "day")
         return UDAT_REL_UNIT_DAY;
     if (singular == "week")
         return UDAT_REL_UNIT_WEEK;
     if (singular == "month")
         return UDAT_REL_UNIT_MONTH;
     if (singular == "quarter")
         return UDAT_REL_UNIT_QUARTER;
     if (singular == "year")
         return UDAT_REL_UNIT_YEAR;

     return WTF::nullopt;
 }

 String IntlRelativeTimeFormat::formatInternal(JSGlobalObject* globalObject, double value, StringView unit) const
 {
     ASSERT(m_relativeDateTimeFormatter);

     VM& vm = globalObject->vm();
     auto scope = DECLARE_THROW_SCOPE(vm);

     if (!std::isfinite(value)) {
         throwRangeError(globalObject, scope, "number argument must be finite"_s);
         return String();
     }

     auto unitType = relativeTimeUnitType(unit);
     if (!unitType) {
         throwRangeError(globalObject, scope, "unit argument is not a recognized unit type"_s);
         return String();
     }

     auto formatRelativeTime = m_numeric ? ureldatefmt_formatNumeric : ureldatefmt_format;

     Vector<UChar, 32> result;
     auto status = callBufferProducingFunction(formatRelativeTime, m_relativeDateTimeFormatter.get(), value, unitType.value(), result);
     if (UNLIKELY(U_FAILURE(status))) {
         throwTypeError(globalObject, scope, "failed to format relative time"_s);
         return String();
     }

     return String(result);
 }

 // https://tc39.es/ecma402/#sec-FormatRelativeTime
 JSValue IntlRelativeTimeFormat::format(JSGlobalObject* globalObject, double value, StringView unit) const
 {
     VM& vm = globalObject->vm();
     auto scope = DECLARE_THROW_SCOPE(vm);

     String result = formatInternal(globalObject, value, unit);
     RETURN_IF_EXCEPTION(scope, { });

     return jsString(vm, result);
 }

 // https://tc39.es/ecma402/#sec-FormatRelativeTimeToParts
 JSValue IntlRelativeTimeFormat::formatToParts(JSGlobalObject* globalObject, double value, StringView unit) const
 {
     VM& vm = globalObject->vm();
     auto scope = DECLARE_THROW_SCOPE(vm);

     String formattedRelativeTime = formatInternal(globalObject, value, unit);
     RETURN_IF_EXCEPTION(scope, { });

     UErrorCode status = U_ZERO_ERROR;
     auto iterator = std::unique_ptr<UFieldPositionIterator, UFieldPositionIteratorDeleter>(ufieldpositer_open(&status));
     ASSERT(U_SUCCESS(status));

     double absValue = std::abs(value);

     Vector<UChar, 32> buffer;
     status = callBufferProducingFunction(unum_formatDoubleForFields, m_numberFormat.get(), absValue, buffer, iterator.get());
     if (U_FAILURE(status))
         return throwTypeError(globalObject, scope, "failed to format relative time"_s);

     auto formattedNumber = String(buffer);

     JSArray* parts = JSArray::tryCreate(vm, globalObject->arrayStructureForIndexingTypeDuringAllocation(ArrayWithContiguous), 0);
     if (!parts)
         return throwOutOfMemoryError(globalObject, scope);

     JSString* literalString = jsNontrivialString(vm, "literal"_s);

     // We only have one input number, so our relative time will have at most one numeric substring,
     // but we need to list all of the numeric parts separately.
     size_t numberEnd = 0;
     size_t numberStart = formattedRelativeTime.find(formattedNumber);
     if (numberStart != notFound) {
         numberEnd = numberStart + buffer.size();

         // Add initial literal if there is one.
         if (numberStart) {
             JSObject* part = constructEmptyObject(globalObject);
             part->putDirect(vm, vm.propertyNames->type, literalString);
             part->putDirect(vm, vm.propertyNames->value, jsSubstring(vm, formattedRelativeTime, 0, numberStart));
             parts->push(globalObject, part);
             RETURN_IF_EXCEPTION(scope, { });
         }

         IntlNumberFormat::formatToPartsInternal(globalObject, absValue, formattedNumber, iterator.get(), parts, jsString(vm, singularUnit(unit).toString()));
         RETURN_IF_EXCEPTION(scope, { });
     }

     // Add final literal if there is one.
     auto stringLength = formattedRelativeTime.length();
     if (numberEnd != stringLength) {
         JSObject* part = constructEmptyObject(globalObject);
         part->putDirect(vm, vm.propertyNames->type, literalString);
         part->putDirect(vm, vm.propertyNames->value, jsSubstring(vm, formattedRelativeTime, numberEnd, stringLength - numberEnd));
         parts->push(globalObject, part);
         RETURN_IF_EXCEPTION(scope, { });
     }

     return parts;
 }

 } // namespace JSC
	/*
	* Copyright (C) 2020 Sony Interactive Entertainment Inc.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution.
	*
	* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
	* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
	* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
	* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
	* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
	* THE POSSIBILITY OF SUCH DAMAGE.
	*/

	#include "config.h"
	#include "IntlRelativeTimeFormat.h"

	#include "Error.h"
	#include "IntlNumberFormat.h"
	#include "IntlObject.h"
	#include "JSGlobalObjectInlines.h"
	#include "ObjectConstructor.h"
	#include <wtf/unicode/icu/ICUHelpers.h>

	namespace JSC {

	const ClassInfo IntlRelativeTimeFormat::s_info = { "Object", &Base::s_info, nullptr, nullptr, CREATE_METHOD_TABLE(IntlRelativeTimeFormat) };

	namespace IntlRelativeTimeFormatInternal {
	constexpr const char* relevantExtensionKeys[1] = { "nu" };
	}

	void IntlRelativeTimeFormat::URelativeDateTimeFormatterDeleter::operator()(URelativeDateTimeFormatter* relativeDateTimeFormatter) const
	{
	if (relativeDateTimeFormatter)
	ureldatefmt_close(relativeDateTimeFormatter);
	}

	void IntlRelativeTimeFormat::UNumberFormatDeleter::operator()(UNumberFormat* numberFormat) const
	{
	if (numberFormat)
	unum_close(numberFormat);
	}

	IntlRelativeTimeFormat* IntlRelativeTimeFormat::create(VM& vm, Structure* structure)
	{
	auto* format = new (NotNull, allocateCell<IntlRelativeTimeFormat>(vm.heap)) IntlRelativeTimeFormat(vm, structure);
	format->finishCreation(vm);
	return format;
	}

	Structure* IntlRelativeTimeFormat::createStructure(VM& vm, JSGlobalObject* globalObject, JSValue prototype)
	{
	return Structure::create(vm, globalObject, prototype, TypeInfo(ObjectType, StructureFlags), info());
	}

	IntlRelativeTimeFormat::IntlRelativeTimeFormat(VM& vm, Structure* structure)
	: Base(vm, structure)
	{
	}

	void IntlRelativeTimeFormat::finishCreation(VM& vm)
	{
	Base::finishCreation(vm);
	ASSERT(inherits(vm, info()));
	}

	void IntlRelativeTimeFormat::visitChildren(JSCell* cell, SlotVisitor& visitor)
	{
	auto* thisObject = jsCast<IntlRelativeTimeFormat*>(cell);
	ASSERT_GC_OBJECT_INHERITS(thisObject, info());

	Base::visitChildren(thisObject, visitor);
	}

	Vector<String> IntlRelativeTimeFormat::localeData(const String& locale, size_t keyIndex)
	{
	// The index of the extension key "nu" in relevantExtensionKeys is 0.
	ASSERT_UNUSED(keyIndex, !keyIndex);
	return numberingSystemsForLocale(locale);
	}

	// https://tc39.es/ecma402/#sec-InitializeRelativeTimeFormat
	void IntlRelativeTimeFormat::initializeRelativeTimeFormat(JSGlobalObject* globalObject, JSValue locales, JSValue optionsValue)
	{
	VM& vm = globalObject->vm();
	auto scope = DECLARE_THROW_SCOPE(vm);

	Vector<String> requestedLocales = canonicalizeLocaleList(globalObject, locales);
	RETURN_IF_EXCEPTION(scope, void());

	JSObject* options;
	if (optionsValue.isUndefined())
	options = constructEmptyObject(vm, globalObject->nullPrototypeObjectStructure());
	else {
	options = optionsValue.toObject(globalObject);
	RETURN_IF_EXCEPTION(scope, void());
	}

	HashMap<String, String> opt;
	String localeMatcher = intlStringOption(globalObject, options, vm.propertyNames->localeMatcher, { "lookup", "best fit" }, "localeMatcher must be either \"lookup\" or \"best fit\"", "best fit");
	RETURN_IF_EXCEPTION(scope, void());
	opt.add(vm.propertyNames->localeMatcher.string(), localeMatcher);

	String numberingSystem = intlStringOption(globalObject, options, vm.propertyNames->numberingSystem, { }, nullptr, nullptr);
	RETURN_IF_EXCEPTION(scope, void());
	if (!numberingSystem.isNull()) {
	if (!isUnicodeLocaleIdentifierType(numberingSystem)) {
	throwRangeError(globalObject, scope, "numberingSystem is not a well-formed numbering system value"_s);
	return;
	}
	opt.add("nu"_s, numberingSystem);
	}

	const HashSet<String>& availableLocales = intlRelativeTimeFormatAvailableLocales();
	HashMap<String, String> resolved = resolveLocale(globalObject, availableLocales, requestedLocales, opt, IntlRelativeTimeFormatInternal::relevantExtensionKeys, WTF_ARRAY_LENGTH(IntlRelativeTimeFormatInternal::relevantExtensionKeys), localeData);
	m_locale = resolved.get(vm.propertyNames->locale.string());
	if (m_locale.isEmpty()) {
	throwTypeError(globalObject, scope, "failed to initialize RelativeTimeFormat due to invalid locale"_s);
	return;
	}

	m_numberingSystem = resolved.get("nu"_s);
	CString dataLocaleWithExtensions = makeString(resolved.get("dataLocale"_s), "-u-nu-", m_numberingSystem).utf8();

	String style = intlStringOption(globalObject, options, vm.propertyNames->style, { "long", "short", "narrow" }, "style must be either \"long\", \"short\", or \"narrow\"", "long");
	RETURN_IF_EXCEPTION(scope, void());
	if (style == "long")
	m_style = UDAT_STYLE_LONG;
	else if (style == "short")
	m_style = UDAT_STYLE_SHORT;
	else if (style == "narrow")
	m_style = UDAT_STYLE_NARROW;
	else
	ASSERT_NOT_REACHED();

	String numeric = intlStringOption(globalObject, options, vm.propertyNames->numeric, { "always", "auto" }, "numeric must be either \"always\" or \"auto\"", "always");
	RETURN_IF_EXCEPTION(scope, void());
	m_numeric = (numeric == "always");

	UErrorCode status = U_ZERO_ERROR;
	m_numberFormat = std::unique_ptr<UNumberFormat, UNumberFormatDeleter>(unum_open(UNUM_DECIMAL, nullptr, 0, dataLocaleWithExtensions.data(), nullptr, &status));
	if (UNLIKELY(U_FAILURE(status))) {
	throwTypeError(globalObject, scope, "failed to initialize RelativeTimeFormat"_s);
	return;
	}

	m_relativeDateTimeFormatter = std::unique_ptr<URelativeDateTimeFormatter, URelativeDateTimeFormatterDeleter>(ureldatefmt_open(dataLocaleWithExtensions.data(), m_numberFormat.get(), m_style, UDISPCTX_CAPITALIZATION_FOR_STANDALONE, &status));
	if (UNLIKELY(U_FAILURE(status))) {
	throwTypeError(globalObject, scope, "failed to initialize RelativeTimeFormat"_s);
	return;
	}
	}

	static ASCIILiteral styleString(UDateRelativeDateTimeFormatterStyle style)
	{
	switch (style) {
	case UDAT_STYLE_LONG:
	return "long"_s;
	case UDAT_STYLE_SHORT:
	return "short"_s;
	case UDAT_STYLE_NARROW:
	return "narrow"_s;
	}
	ASSERT_NOT_REACHED();
	return ASCIILiteral::null();
	}

	static ASCIILiteral numericString(bool numeric)
	{
	return numeric ? "always"_s : "auto"_s;
	}

	// https://tc39.es/ecma402/#sec-intl.relativetimeformat.prototype.resolvedoptions
	JSObject* IntlRelativeTimeFormat::resolvedOptions(JSGlobalObject* globalObject) const
	{
	VM& vm = globalObject->vm();
	JSObject* options = constructEmptyObject(globalObject);
	options->putDirect(vm, vm.propertyNames->locale, jsNontrivialString(vm, m_locale));
	options->putDirect(vm, vm.propertyNames->style, jsNontrivialString(vm, styleString(m_style)));
	options->putDirect(vm, vm.propertyNames->numeric, jsNontrivialString(vm, numericString(m_numeric)));
	options->putDirect(vm, vm.propertyNames->numberingSystem, jsNontrivialString(vm, m_numberingSystem));
	return options;
	}

	static StringView singularUnit(StringView unit)
	{
	// Plurals are allowed, but thankfully they're all just a simple -s.
	return unit.endsWith("s") ? unit.left(unit.length() - 1) : unit;
	}

	// https://tc39.es/ecma402/#sec-singularrelativetimeunit
	static Optional<URelativeDateTimeUnit> relativeTimeUnitType(StringView unit)
	{
	StringView singular = singularUnit(unit);

	if (singular == "second")
	return UDAT_REL_UNIT_SECOND;
	if (singular == "minute")
	return UDAT_REL_UNIT_MINUTE;
	if (singular == "hour")
	return UDAT_REL_UNIT_HOUR;
	if (singular == "day")
	return UDAT_REL_UNIT_DAY;
	if (singular == "week")
	return UDAT_REL_UNIT_WEEK;
	if (singular == "month")
	return UDAT_REL_UNIT_MONTH;
	if (singular == "quarter")
	return UDAT_REL_UNIT_QUARTER;
	if (singular == "year")
	return UDAT_REL_UNIT_YEAR;

	return WTF::nullopt;
	}

	String IntlRelativeTimeFormat::formatInternal(JSGlobalObject* globalObject, double value, StringView unit) const
	{
	ASSERT(m_relativeDateTimeFormatter);

	VM& vm = globalObject->vm();
	auto scope = DECLARE_THROW_SCOPE(vm);

	if (!std::isfinite(value)) {
	throwRangeError(globalObject, scope, "number argument must be finite"_s);
	return String();
	}

	auto unitType = relativeTimeUnitType(unit);
	if (!unitType) {
	throwRangeError(globalObject, scope, "unit argument is not a recognized unit type"_s);
	return String();
	}

	auto formatRelativeTime = m_numeric ? ureldatefmt_formatNumeric : ureldatefmt_format;

	Vector<UChar, 32> result;
	auto status = callBufferProducingFunction(formatRelativeTime, m_relativeDateTimeFormatter.get(), value, unitType.value(), result);
	if (UNLIKELY(U_FAILURE(status))) {
	throwTypeError(globalObject, scope, "failed to format relative time"_s);
	return String();
	}

	return String(result);
	}

	// https://tc39.es/ecma402/#sec-FormatRelativeTime
	JSValue IntlRelativeTimeFormat::format(JSGlobalObject* globalObject, double value, StringView unit) const
	{
	VM& vm = globalObject->vm();
	auto scope = DECLARE_THROW_SCOPE(vm);

	String result = formatInternal(globalObject, value, unit);
	RETURN_IF_EXCEPTION(scope, { });

	return jsString(vm, result);
	}

	// https://tc39.es/ecma402/#sec-FormatRelativeTimeToParts
	JSValue IntlRelativeTimeFormat::formatToParts(JSGlobalObject* globalObject, double value, StringView unit) const
	{
	VM& vm = globalObject->vm();
	auto scope = DECLARE_THROW_SCOPE(vm);

	String formattedRelativeTime = formatInternal(globalObject, value, unit);
	RETURN_IF_EXCEPTION(scope, { });

	UErrorCode status = U_ZERO_ERROR;
	auto iterator = std::unique_ptr<UFieldPositionIterator, UFieldPositionIteratorDeleter>(ufieldpositer_open(&status));
	ASSERT(U_SUCCESS(status));

	double absValue = std::abs(value);

	Vector<UChar, 32> buffer;
	status = callBufferProducingFunction(unum_formatDoubleForFields, m_numberFormat.get(), absValue, buffer, iterator.get());
	if (U_FAILURE(status))
	return throwTypeError(globalObject, scope, "failed to format relative time"_s);

	auto formattedNumber = String(buffer);

	JSArray* parts = JSArray::tryCreate(vm, globalObject->arrayStructureForIndexingTypeDuringAllocation(ArrayWithContiguous), 0);
	if (!parts)
	return throwOutOfMemoryError(globalObject, scope);

	JSString* literalString = jsNontrivialString(vm, "literal"_s);

	// We only have one input number, so our relative time will have at most one numeric substring,
	// but we need to list all of the numeric parts separately.
	size_t numberEnd = 0;
	size_t numberStart = formattedRelativeTime.find(formattedNumber);
	if (numberStart != notFound) {
	numberEnd = numberStart + buffer.size();

	// Add initial literal if there is one.
	if (numberStart) {
	JSObject* part = constructEmptyObject(globalObject);
	part->putDirect(vm, vm.propertyNames->type, literalString);
	part->putDirect(vm, vm.propertyNames->value, jsSubstring(vm, formattedRelativeTime, 0, numberStart));
	parts->push(globalObject, part);
	RETURN_IF_EXCEPTION(scope, { });
	}

	IntlNumberFormat::formatToPartsInternal(globalObject, absValue, formattedNumber, iterator.get(), parts, jsString(vm, singularUnit(unit).toString()));
	RETURN_IF_EXCEPTION(scope, { });
	}

	// Add final literal if there is one.
	auto stringLength = formattedRelativeTime.length();
	if (numberEnd != stringLength) {
	JSObject* part = constructEmptyObject(globalObject);
	part->putDirect(vm, vm.propertyNames->type, literalString);
	part->putDirect(vm, vm.propertyNames->value, jsSubstring(vm, formattedRelativeTime, numberEnd, stringLength - numberEnd));
	parts->push(globalObject, part);
	RETURN_IF_EXCEPTION(scope, { });
	}

	return parts;
	}

	} // namespace JSC