scuffed-code/icu4c/source/i18n/numparse_decimal.cpp

332 lines
12 KiB
C++

// © 2018 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
#include "unicode/utypes.h"
#if !UCONFIG_NO_FORMATTING
// Allow implicit conversion from char16_t* to UnicodeString for this file:
// Helpful in toString methods and elsewhere.
#define UNISTR_FROM_STRING_EXPLICIT
#include "numparse_types.h"
#include "numparse_decimal.h"
#include "numparse_unisets.h"
#include "numparse_utils.h"
#include "unicode/uchar.h"
#include "putilimp.h"
using namespace icu;
using namespace icu::numparse;
using namespace icu::numparse::impl;
DecimalMatcher::DecimalMatcher(const DecimalFormatSymbols& symbols, const Grouper& grouper,
parse_flags_t parseFlags) {
if (0 != (parseFlags & PARSE_FLAG_MONETARY_SEPARATORS)) {
groupingSeparator = symbols.getConstSymbol(DecimalFormatSymbols::kMonetaryGroupingSeparatorSymbol);
decimalSeparator = symbols.getConstSymbol(DecimalFormatSymbols::kMonetarySeparatorSymbol);
} else {
groupingSeparator = symbols.getConstSymbol(DecimalFormatSymbols::kGroupingSeparatorSymbol);
decimalSeparator = symbols.getConstSymbol(DecimalFormatSymbols::kDecimalSeparatorSymbol);
}
bool strictSeparators = 0 != (parseFlags & PARSE_FLAG_STRICT_SEPARATORS);
unisets::Key groupingKey = strictSeparators ? unisets::STRICT_ALL_SEPARATORS
: unisets::ALL_SEPARATORS;
// Attempt to find separators in the static cache
groupingUniSet = unisets::get(groupingKey);
unisets::Key decimalKey = unisets::chooseFrom(
decimalSeparator,
strictSeparators ? unisets::STRICT_COMMA : unisets::COMMA,
strictSeparators ? unisets::STRICT_PERIOD : unisets::PERIOD);
if (decimalKey != unisets::COUNT) {
decimalUniSet = unisets::get(decimalKey);
} else {
auto* set = new UnicodeSet();
set->add(decimalSeparator.char32At(0));
set->freeze();
decimalUniSet = set;
fLocalDecimalUniSet.adoptInstead(set);
}
if (groupingKey != unisets::COUNT && decimalKey != unisets::COUNT) {
// Everything is available in the static cache
separatorSet = groupingUniSet;
leadSet = unisets::get(
strictSeparators ? unisets::DIGITS_OR_ALL_SEPARATORS
: unisets::DIGITS_OR_STRICT_ALL_SEPARATORS);
} else {
auto* set = new UnicodeSet();
set->addAll(*groupingUniSet);
set->addAll(*decimalUniSet);
set->freeze();
separatorSet = set;
fLocalSeparatorSet.adoptInstead(set);
leadSet = nullptr;
}
int cpZero = symbols.getCodePointZero();
if (cpZero == -1 || !u_isdigit(cpZero) || u_digit(cpZero, 10) != 0) {
// Uncommon case: okay to allocate.
auto digitStrings = new UnicodeString[10];
fLocalDigitStrings.adoptInstead(digitStrings);
for (int32_t i = 0; i <= 9; i++) {
digitStrings[i] = symbols.getConstDigitSymbol(i);
}
}
requireGroupingMatch = 0 != (parseFlags & PARSE_FLAG_STRICT_GROUPING_SIZE);
groupingDisabled = 0 != (parseFlags & PARSE_FLAG_GROUPING_DISABLED);
fractionGroupingDisabled = 0 != (
parseFlags & PARSE_FLAG_FRACTION_GROUPING_DISABLED);
integerOnly = 0 != (parseFlags & PARSE_FLAG_INTEGER_ONLY);
grouping1 = grouper.getPrimary();
grouping2 = grouper.getSecondary();
}
bool DecimalMatcher::match(StringSegment& segment, ParsedNumber& result, UErrorCode& status) const {
return match(segment, result, 0, status);
}
bool DecimalMatcher::match(StringSegment& segment, ParsedNumber& result, int8_t exponentSign,
UErrorCode&) const {
if (result.seenNumber() && exponentSign == 0) {
// A number has already been consumed.
return false;
} else if (exponentSign != 0) {
// scientific notation always comes after the number
U_ASSERT(!result.quantity.bogus);
}
ParsedNumber backupResult(result);
// strict parsing
bool strictFail = false; // did we exit with a strict parse failure?
UnicodeString actualGroupingString = groupingSeparator;
UnicodeString actualDecimalString = decimalSeparator;
int32_t groupedDigitCount = 0; // tracking count of digits delimited by grouping separator
int32_t backupOffset = -1; // used for preserving the last confirmed position
bool afterFirstGrouping = false;
bool seenGrouping = false;
bool seenDecimal = false;
int32_t digitsAfterDecimal = 0;
int32_t initialOffset = segment.getOffset();
int32_t exponent = 0;
bool hasPartialPrefix = false;
while (segment.length() > 0) {
hasPartialPrefix = false;
// Attempt to match a digit.
int8_t digit = -1;
// Try by code point digit value.
int cp = segment.getCodePoint();
if (u_isdigit(cp)) {
segment.adjustOffset(U16_LENGTH(cp));
digit = static_cast<int8_t>(u_digit(cp, 10));
}
// Try by digit string.
if (digit == -1 && !fLocalDigitStrings.isNull()) {
for (int i = 0; i < 10; i++) {
const UnicodeString& str = fLocalDigitStrings[i];
int overlap = segment.getCommonPrefixLength(str);
if (overlap == str.length()) {
segment.adjustOffset(overlap);
digit = static_cast<int8_t>(i);
break;
} else if (overlap == segment.length()) {
hasPartialPrefix = true;
}
}
}
if (digit >= 0) {
// Digit was found.
// Check for grouping size violation
if (backupOffset != -1) {
if (requireGroupingMatch) {
// comma followed by digit, so group before comma is a secondary
// group. If there was a group separator before that, the group
// must == the secondary group length, else it can be <= the the
// secondary group length.
if ((afterFirstGrouping && groupedDigitCount != grouping2) ||
(!afterFirstGrouping && groupedDigitCount > grouping2)) {
strictFail = true;
break;
}
}
afterFirstGrouping = true;
backupOffset = -1;
groupedDigitCount = 0;
}
// Save the digit in the DecimalQuantity or scientific adjustment.
if (exponentSign != 0) {
int32_t nextExponent;
// i.e., nextExponent = exponent * 10 + digit
UBool overflow = uprv_mul32_overflow(exponent, 10, &nextExponent) ||
uprv_add32_overflow(nextExponent, digit, &nextExponent);
if (overflow) {
exponent = INT32_MAX;
} else {
exponent = nextExponent;
}
} else {
if (result.quantity.bogus) {
result.quantity.bogus = false;
}
result.quantity.appendDigit(digit, 0, true);
}
result.setCharsConsumed(segment);
groupedDigitCount++;
if (seenDecimal) {
digitsAfterDecimal++;
}
continue;
}
// Attempt to match a literal grouping or decimal separator
int32_t decimalOverlap = segment.getCommonPrefixLength(actualDecimalString);
bool decimalStringMatch = decimalOverlap == actualDecimalString.length();
int32_t groupingOverlap = segment.getCommonPrefixLength(actualGroupingString);
bool groupingStringMatch = groupingOverlap == actualGroupingString.length();
hasPartialPrefix = (decimalOverlap == segment.length()) || (groupingOverlap == segment.length());
if (!seenDecimal && !groupingStringMatch &&
(decimalStringMatch || (!seenDecimal && decimalUniSet->contains(cp)))) {
// matched a decimal separator
if (requireGroupingMatch) {
if (backupOffset != -1 || (seenGrouping && groupedDigitCount != grouping1)) {
strictFail = true;
break;
}
}
// If we're only parsing integers, then don't parse this one.
if (integerOnly) {
break;
}
seenDecimal = true;
if (!decimalStringMatch) {
actualDecimalString = UnicodeString(cp);
}
segment.adjustOffset(actualDecimalString.length());
result.setCharsConsumed(segment);
result.flags |= FLAG_HAS_DECIMAL_SEPARATOR;
continue;
}
if (!groupingDisabled && !decimalStringMatch &&
(groupingStringMatch || (!seenGrouping && groupingUniSet->contains(cp)))) {
// matched a grouping separator
if (requireGroupingMatch) {
if (groupedDigitCount == 0) {
// leading group
strictFail = true;
break;
} else if (backupOffset != -1) {
// two group separators in a row
break;
}
}
if (fractionGroupingDisabled && seenDecimal) {
// Stop parsing here.
break;
}
seenGrouping = true;
if (!groupingStringMatch) {
actualGroupingString = UnicodeString(cp);
}
backupOffset = segment.getOffset();
segment.adjustOffset(actualGroupingString.length());
// Note: do NOT set charsConsumed
continue;
}
// Not a digit and not a separator
break;
}
// Back up if there was a trailing grouping separator
if (backupOffset != -1) {
segment.setOffset(backupOffset);
hasPartialPrefix = true; // redundant with `groupingOverlap == segment.length()`
}
// Check the final grouping for validity
if (requireGroupingMatch && !seenDecimal && seenGrouping && afterFirstGrouping &&
groupedDigitCount != grouping1) {
strictFail = true;
}
if (requireGroupingMatch && strictFail) {
result = backupResult;
segment.setOffset(initialOffset);
}
if (result.quantity.bogus && segment.getOffset() != initialOffset) {
// Strings that start with a separator but have no digits.
// We don't need a backup of ParsedNumber because no changes could have been made to it.
segment.setOffset(initialOffset);
hasPartialPrefix = true;
}
if (!result.quantity.bogus) {
// The final separator was a decimal separator.
result.quantity.adjustMagnitude(-digitsAfterDecimal);
}
if (exponentSign != 0 && segment.getOffset() != initialOffset) {
U_ASSERT(!result.quantity.bogus);
bool overflow = (exponent == INT32_MAX);
if (!overflow) {
overflow = result.quantity.adjustMagnitude(exponentSign * exponent);
}
if (overflow) {
if (exponentSign == -1) {
// Set to zero
result.quantity.clear();
} else {
// Set to infinity
result.quantity.bogus = true;
result.flags |= FLAG_INFINITY;
}
}
}
return segment.length() == 0 || hasPartialPrefix;
}
bool DecimalMatcher::smokeTest(const StringSegment& segment) const {
// The common case uses a static leadSet for efficiency.
if (fLocalDigitStrings.isNull() && leadSet != nullptr) {
return segment.startsWith(*leadSet);
}
if (segment.startsWith(*separatorSet) || u_isdigit(segment.getCodePoint())) {
return true;
}
if (fLocalDigitStrings.isNull()) {
return false;
}
for (int i = 0; i < 10; i++) {
if (segment.startsWith(fLocalDigitStrings[i])) {
return true;
}
}
return false;
}
UnicodeString DecimalMatcher::toString() const {
return u"<Decimal>";
}
#endif /* #if !UCONFIG_NO_FORMATTING */