Function formatNumber

Sources/Shared/Base/Format.cpp:227–315

	template<typename T>
	constexpr std::int32_t formatNumber(const Containers::MutableStringView& buffer, T value, FormatContext& context) {
		std::int32_t precision = context.Precision;
		if (precision == -1) {
			precision = 1;
		}

		switch (context.Type) {
			case FormatType::Character: {
				if (1 <= buffer.size()) {
					char* begin = buffer.data();
					*begin = static_cast<char>(value);
				}
				return 1;
			}
			case FormatType::Unspecified:
			case FormatType::Decimal: {
				auto absValue = static_cast<uint32_or_64_t<T>>(value);
				bool negative = isNegative(value);
				if (negative) absValue = ~absValue + 1;

				std::int32_t digitCount = countDigits(absValue);
				std::int32_t size = (negative ? 1 : 0) + (digitCount < precision ? precision : digitCount);

				if (size <= buffer.size()) {
					char* begin = buffer.data();
					if (negative) {
						*begin++ = '-';
					}
					if (digitCount < precision) {
						for (std::int32_t i = 0; i < precision - digitCount; i++) {
							*begin++ = '0';
						}
					}
					formatDecimal(begin, absValue, digitCount);
				}

				return size;
			}
			case FormatType::Octal: {
				auto absValue = static_cast<uint32_or_64_t<T>>(value);

				std::int32_t digitCount = countDigits<3>(absValue);
				std::int32_t size = (digitCount < precision ? precision : digitCount + 1);

				if (size <= buffer.size()) {
					char* begin = buffer.data();
					if (digitCount < precision) {
						for (std::int32_t i = 0; i < precision - digitCount; i++) {
							*begin++ = '0';
						}
					} else {
						*begin++ = '0'; // '0' prefix for octal numbers
					}
					formatBase2e<3>(begin, absValue, digitCount, false);
				}

				return size;
			}