icuSources/i18n/numparse_decimal.cpp

   1 // © 2018 and later: Unicode, Inc. and others.
   2 // License & terms of use: http://www.unicode.org/copyright.html
   3
   4 #include "unicode/utypes.h"
   5
   6 #if !UCONFIG_NO_FORMATTING
   7
   8 // Allow implicit conversion from char16_t* to UnicodeString for this file:
   9 // Helpful in toString methods and elsewhere.
  10 #define UNISTR_FROM_STRING_EXPLICIT
  11
  12 #include "numparse_types.h"
  13 #include "numparse_decimal.h"
  14 #include "static_unicode_sets.h"
  15 #include "numparse_utils.h"
  16 #include "unicode/uchar.h"
  17 #include "putilimp.h"
  18 #include "number_decimalquantity.h"
  19
  20 using namespace icu;
  21 using namespace icu::numparse;
  22 using namespace icu::numparse::impl;
  23
  24
  25 DecimalMatcher::DecimalMatcher(const DecimalFormatSymbols& symbols, const Grouper& grouper,
  26                                parse_flags_t parseFlags) {
  27     if (0 != (parseFlags & PARSE_FLAG_MONETARY_SEPARATORS)) {
  28         groupingSeparator = symbols.getConstSymbol(DecimalFormatSymbols::kMonetaryGroupingSeparatorSymbol);
  29         decimalSeparator = symbols.getConstSymbol(DecimalFormatSymbols::kMonetarySeparatorSymbol);
  30     } else {
  31         groupingSeparator = symbols.getConstSymbol(DecimalFormatSymbols::kGroupingSeparatorSymbol);
  32         decimalSeparator = symbols.getConstSymbol(DecimalFormatSymbols::kDecimalSeparatorSymbol);
  33     }
  34     bool strictSeparators = 0 != (parseFlags & PARSE_FLAG_STRICT_SEPARATORS);
  35     unisets::Key groupingKey = strictSeparators ? unisets::STRICT_ALL_SEPARATORS
  36                                                 : unisets::ALL_SEPARATORS;
  37
  38     // Attempt to find separators in the static cache
  39
  40     groupingUniSet = unisets::get(groupingKey);
  41     unisets::Key decimalKey = unisets::chooseFrom(
  42             decimalSeparator,
  43             strictSeparators ? unisets::STRICT_COMMA : unisets::COMMA,
  44             strictSeparators ? unisets::STRICT_PERIOD : unisets::PERIOD);
  45     if (decimalKey >= 0) {
  46         decimalUniSet = unisets::get(decimalKey);
  47     } else if (!decimalSeparator.isEmpty()) {
  48         auto* set = new UnicodeSet();
  49         set->add(decimalSeparator.char32At(0));
  50         set->freeze();
  51         decimalUniSet = set;
  52         fLocalDecimalUniSet.adoptInstead(set);
  53     } else {
  54         decimalUniSet = unisets::get(unisets::EMPTY);
  55     }
  56
  57     if (groupingKey >= 0 && decimalKey >= 0) {
  58         // Everything is available in the static cache
  59         separatorSet = groupingUniSet;
  60         leadSet = unisets::get(
  61                 strictSeparators ? unisets::DIGITS_OR_ALL_SEPARATORS
  62                                  : unisets::DIGITS_OR_STRICT_ALL_SEPARATORS);
  63     } else {
  64         auto* set = new UnicodeSet();
  65         set->addAll(*groupingUniSet);
  66         set->addAll(*decimalUniSet);
  67         set->freeze();
  68         separatorSet = set;
  69         fLocalSeparatorSet.adoptInstead(set);
  70         leadSet = nullptr;
  71     }
  72
  73     UChar32 cpZero = symbols.getCodePointZero();
  74     if (cpZero == -1 || !u_isdigit(cpZero) || u_digit(cpZero, 10) != 0) {
  75         // Uncommon case: okay to allocate.
  76         auto digitStrings = new UnicodeString[10];
  77         fLocalDigitStrings.adoptInstead(digitStrings);
  78         for (int32_t i = 0; i <= 9; i++) {
  79             digitStrings[i] = symbols.getConstDigitSymbol(i);
  80         }
  81     }
  82
  83     requireGroupingMatch = 0 != (parseFlags & PARSE_FLAG_STRICT_GROUPING_SIZE);
  84     groupingDisabled = 0 != (parseFlags & PARSE_FLAG_GROUPING_DISABLED);
  85     integerOnly = 0 != (parseFlags & PARSE_FLAG_INTEGER_ONLY);
  86     grouping1 = grouper.getPrimary();
  87     grouping2 = grouper.getSecondary();
  88
  89     // Fraction grouping parsing is disabled for now but could be enabled later.
  90     // See http://bugs.icu-project.org/trac/ticket/10794
  91     // fractionGrouping = 0 != (parseFlags & PARSE_FLAG_FRACTION_GROUPING_ENABLED);
  92 }
  93
  94 bool DecimalMatcher::match(StringSegment& segment, ParsedNumber& result, UErrorCode& status) const {
  95     return match(segment, result, 0, status);
  96 }
  97
  98 bool DecimalMatcher::match(StringSegment& segment, ParsedNumber& result, int8_t exponentSign,
  99                            UErrorCode&) const {
 100     if (result.seenNumber() && exponentSign == 0) {
 101         // A number has already been consumed.
 102         return false;
 103     } else if (exponentSign != 0) {
 104         // scientific notation always comes after the number
 105         U_ASSERT(!result.quantity.bogus);
 106     }
 107
 108     // Initial offset before any character consumption.
 109     int32_t initialOffset = segment.getOffset();
 110
 111     // Return value: whether to ask for more characters.
 112     bool maybeMore = false;
 113
 114     // All digits consumed so far.
 115     number::impl::DecimalQuantity digitsConsumed;
 116     digitsConsumed.bogus = true;
 117
 118     // The total number of digits after the decimal place, used for scaling the result.
 119     int32_t digitsAfterDecimalPlace = 0;
 120
 121     // The actual grouping and decimal separators used in the string.
 122     // If non-null, we have seen that token.
 123     UnicodeString actualGroupingString;
 124     UnicodeString actualDecimalString;
 125     actualGroupingString.setToBogus();
 126     actualDecimalString.setToBogus();
 127
 128     // Information for two groups: the previous group and the current group.
 129     //
 130     // Each group has three pieces of information:
 131     //
 132     // Offset: the string position of the beginning of the group, including a leading separator
 133     // if there was a leading separator. This is needed in case we need to rewind the parse to
 134     // that position.
 135     //
 136     // Separator type:
 137     // 0 => beginning of string
 138     // 1 => lead separator is a grouping separator
 139     // 2 => lead separator is a decimal separator
 140     //
 141     // Count: the number of digits in the group. If -1, the group has been validated.
 142     int32_t currGroupOffset = 0;
 143     int32_t currGroupSepType = 0;
 144     int32_t currGroupCount = 0;
 145     int32_t prevGroupOffset = -1;
 146     int32_t prevGroupSepType = -1;
 147     int32_t prevGroupCount = -1;
 148
 149     while (segment.length() > 0) {
 150         maybeMore = false;
 151
 152         // Attempt to match a digit.
 153         int8_t digit = -1;
 154
 155         // Try by code point digit value.
 156         UChar32 cp = segment.getCodePoint();
 157         if (u_isdigit(cp)) {
 158             segment.adjustOffset(U16_LENGTH(cp));
 159             digit = static_cast<int8_t>(u_digit(cp, 10));
 160         }
 161
 162         // Try by digit string.
 163         if (digit == -1 && !fLocalDigitStrings.isNull()) {
 164             for (int32_t i = 0; i < 10; i++) {
 165                 const UnicodeString& str = fLocalDigitStrings[i];
 166                 if (str.isEmpty()) {
 167                     continue;
 168                 }
 169                 int32_t overlap = segment.getCommonPrefixLength(str);
 170                 if (overlap == str.length()) {
 171                     segment.adjustOffset(overlap);
 172                     digit = static_cast<int8_t>(i);
 173                     break;
 174                 }
 175                 maybeMore = maybeMore || (overlap == segment.length());
 176             }
 177         }
 178
 179         if (digit >= 0) {
 180             // Digit was found.
 181             if (digitsConsumed.bogus) {
 182                 digitsConsumed.bogus = false;
 183                 digitsConsumed.clear();
 184             }
 185             digitsConsumed.appendDigit(digit, 0, true);
 186             currGroupCount++;
 187             if (!actualDecimalString.isBogus()) {
 188                 digitsAfterDecimalPlace++;
 189             }
 190             continue;
 191         }
 192
 193         // Attempt to match a literal grouping or decimal separator.
 194         bool isDecimal = false;
 195         bool isGrouping = false;
 196
 197         // 1) Attempt the decimal separator string literal.
 198         // if (we have not seen a decimal separator yet) { ... }
 199         if (actualDecimalString.isBogus() && !decimalSeparator.isEmpty()) {
 200             int32_t overlap = segment.getCommonPrefixLength(decimalSeparator);
 201             maybeMore = maybeMore || (overlap == segment.length());
 202             if (overlap == decimalSeparator.length()) {
 203                 isDecimal = true;
 204                 actualDecimalString = decimalSeparator;
 205             }
 206         }
 207
 208         // 2) Attempt to match the actual grouping string literal.
 209         if (!actualGroupingString.isBogus()) {
 210             int32_t overlap = segment.getCommonPrefixLength(actualGroupingString);
 211             maybeMore = maybeMore || (overlap == segment.length());
 212             if (overlap == actualGroupingString.length()) {
 213                 isGrouping = true;
 214             }
 215         }
 216
 217         // 2.5) Attempt to match a new the grouping separator string literal.
 218         // if (we have not seen a grouping or decimal separator yet) { ... }
 219         if (!groupingDisabled && actualGroupingString.isBogus() && actualDecimalString.isBogus() &&
 220             !groupingSeparator.isEmpty()) {
 221             int32_t overlap = segment.getCommonPrefixLength(groupingSeparator);
 222             maybeMore = maybeMore || (overlap == segment.length());
 223             if (overlap == groupingSeparator.length()) {
 224                 isGrouping = true;
 225                 actualGroupingString = groupingSeparator;
 226             }
 227         }
 228
 229         // 3) Attempt to match a decimal separator from the equivalence set.
 230         // if (we have not seen a decimal separator yet) { ... }
 231         // The !isGrouping is to confirm that we haven't yet matched the current character.
 232         if (!isGrouping && actualDecimalString.isBogus()) {
 233             if (decimalUniSet->contains(cp)) {
 234                 isDecimal = true;
 235                 actualDecimalString = UnicodeString(cp);
 236             }
 237         }
 238
 239         // 4) Attempt to match a grouping separator from the equivalence set.
 240         // if (we have not seen a grouping or decimal separator yet) { ... }
 241         if (!groupingDisabled && actualGroupingString.isBogus() && actualDecimalString.isBogus()) {
 242             if (groupingUniSet->contains(cp)) {
 243                 isGrouping = true;
 244                 actualGroupingString = UnicodeString(cp);
 245             }
 246         }
 247
 248         // Leave if we failed to match this as a separator.
 249         if (!isDecimal && !isGrouping) {
 250             break;
 251         }
 252
 253         // Check for conditions when we don't want to accept the separator.
 254         if (isDecimal && integerOnly) {
 255             break;
 256         } else if (currGroupSepType == 2 && isGrouping) {
 257             // Fraction grouping
 258             break;
 259         }
 260
 261         // Validate intermediate grouping sizes.
 262         bool prevValidSecondary = validateGroup(prevGroupSepType, prevGroupCount, false);
 263         bool currValidPrimary = validateGroup(currGroupSepType, currGroupCount, true);
 264         if (!prevValidSecondary || (isDecimal && !currValidPrimary)) {
 265             // Invalid grouping sizes.
 266             if (isGrouping && currGroupCount == 0) {
 267                 // Trailing grouping separators: these are taken care of below
 268                 U_ASSERT(currGroupSepType == 1);
 269             } else if (requireGroupingMatch) {
 270                 // Strict mode: reject the parse
 271                 digitsConsumed.clear();
 272                 digitsConsumed.bogus = true;
 273             }
 274             break;
 275         } else if (requireGroupingMatch && currGroupCount == 0 && currGroupSepType == 1) {
 276             break;
 277         } else {
 278             // Grouping sizes OK so far.
 279             prevGroupOffset = currGroupOffset;
 280             prevGroupCount = currGroupCount;
 281             if (isDecimal) {
 282                 // Do not validate this group any more.
 283                 prevGroupSepType = -1;
 284             } else {
 285                 prevGroupSepType = currGroupSepType;
 286             }
 287         }
 288
 289         // OK to accept the separator.
 290         // Special case: don't update currGroup if it is empty; this allows two grouping
 291         // separators in a row in lenient mode.
 292         if (currGroupCount != 0) {
 293             currGroupOffset = segment.getOffset();
 294         }
 295         currGroupSepType = isGrouping ? 1 : 2;
 296         currGroupCount = 0;
 297         if (isGrouping) {
 298             segment.adjustOffset(actualGroupingString.length());
 299         } else {
 300             segment.adjustOffset(actualDecimalString.length());
 301         }
 302     }
 303
 304     // End of main loop.
 305     // Back up if there was a trailing grouping separator.
 306     // Shift prev -> curr so we can check it as a final group.
 307     if (currGroupSepType != 2 && currGroupCount == 0) {
 308         maybeMore = true;
 309         segment.setOffset(currGroupOffset);
 310         currGroupOffset = prevGroupOffset;
 311         currGroupSepType = prevGroupSepType;
 312         currGroupCount = prevGroupCount;
 313         prevGroupOffset = -1;
 314         prevGroupSepType = 0;
 315         prevGroupCount = 1;
 316     }
 317
 318     // Validate final grouping sizes.
 319     bool prevValidSecondary = validateGroup(prevGroupSepType, prevGroupCount, false);
 320     bool currValidPrimary = validateGroup(currGroupSepType, currGroupCount, true);
 321     if (!requireGroupingMatch) {
 322         // The cases we need to handle here are lone digits.
 323         // Examples: "1,1"  "1,1,"  "1,1,1"  "1,1,1,"  ",1" (all parse as 1)
 324         // See more examples in numberformattestspecification.txt
 325         int32_t digitsToRemove = 0;
 326         if (!prevValidSecondary) {
 327             segment.setOffset(prevGroupOffset);
 328             digitsToRemove += prevGroupCount;
 329             digitsToRemove += currGroupCount;
 330         } else if (!currValidPrimary && (prevGroupSepType != 0 || prevGroupCount != 0)) {
 331             maybeMore = true;
 332             segment.setOffset(currGroupOffset);
 333             digitsToRemove += currGroupCount;
 334         }
 335         if (digitsToRemove != 0) {
 336             digitsConsumed.adjustMagnitude(-digitsToRemove);
 337             digitsConsumed.truncate();
 338         }
 339         prevValidSecondary = true;
 340         currValidPrimary = true;
 341     }
 342     if (currGroupSepType != 2 && (!prevValidSecondary || !currValidPrimary)) {
 343         // Grouping failure.
 344         digitsConsumed.bogus = true;
 345     }
 346
 347     // Strings that start with a separator but have no digits,
 348     // or strings that failed a grouping size check.
 349     if (digitsConsumed.bogus) {
 350         maybeMore = maybeMore || (segment.length() == 0);
 351         segment.setOffset(initialOffset);
 352         return maybeMore;
 353     }
 354
 355     // We passed all inspections. Start post-processing.
 356
 357     // Adjust for fraction part.
 358     digitsConsumed.adjustMagnitude(-digitsAfterDecimalPlace);
 359
 360     // Set the digits, either normal or exponent.
 361     if (exponentSign != 0 && segment.getOffset() != initialOffset) {
 362         bool overflow = false;
 363         if (digitsConsumed.fitsInLong()) {
 364             int64_t exponentLong = digitsConsumed.toLong(false);
 365             U_ASSERT(exponentLong >= 0);
 366             if (exponentLong <= INT32_MAX) {
 367                 auto exponentInt = static_cast<int32_t>(exponentLong);
 368                 if (result.quantity.adjustMagnitude(exponentSign * exponentInt)) {
 369                     overflow = true;
 370                 }
 371             } else {
 372                 overflow = true;
 373             }
 374         } else {
 375             overflow = true;
 376         }
 377         if (overflow) {
 378             if (exponentSign == -1) {
 379                 // Set to zero
 380                 result.quantity.clear();
 381             } else {
 382                 // Set to infinity
 383                 result.quantity.bogus = true;
 384                 result.flags |= FLAG_INFINITY;
 385             }
 386         }
 387     } else {
 388         result.quantity = digitsConsumed;
 389     }
 390
 391     // Set other information into the result and return.
 392     if (!actualDecimalString.isBogus()) {
 393         result.flags |= FLAG_HAS_DECIMAL_SEPARATOR;
 394     }
 395     result.setCharsConsumed(segment);
 396     return segment.length() == 0 || maybeMore;
 397 }
 398
 399 bool DecimalMatcher::validateGroup(int32_t sepType, int32_t count, bool isPrimary) const {
 400     if (requireGroupingMatch) {
 401         if (sepType == -1) {
 402             // No such group (prevGroup before first shift).
 403             return true;
 404         } else if (sepType == 0) {
 405             // First group.
 406             if (isPrimary) {
 407                 // No grouping separators is OK.
 408                 return true;
 409             } else {
 410                 return count != 0 && count <= grouping2;
 411             }
 412         } else if (sepType == 1) {
 413             // Middle group.
 414             if (isPrimary) {
 415                 return count == grouping1;
 416             } else {
 417                 return count == grouping2;
 418             }
 419         } else {
 420             U_ASSERT(sepType == 2);
 421             // After the decimal separator.
 422             return true;
 423         }
 424     } else {
 425         if (sepType == 1) {
 426             // #11230: don't accept middle groups with only 1 digit.
 427             return count != 1;
 428         } else {
 429             return true;
 430         }
 431     }
 432 }
 433
 434 bool DecimalMatcher::smokeTest(const StringSegment& segment) const {
 435     // The common case uses a static leadSet for efficiency.
 436     if (fLocalDigitStrings.isNull() && leadSet != nullptr) {
 437         return segment.startsWith(*leadSet);
 438     }
 439     if (segment.startsWith(*separatorSet) || u_isdigit(segment.getCodePoint())) {
 440         return true;
 441     }
 442     if (fLocalDigitStrings.isNull()) {
 443         return false;
 444     }
 445     for (int32_t i = 0; i < 10; i++) {
 446         if (segment.startsWith(fLocalDigitStrings[i])) {
 447             return true;
 448         }
 449     }
 450     return false;
 451 }
 452
 453 UnicodeString DecimalMatcher::toString() const {
 454     return u"<Decimal>";
 455 }
 456
 457
 458 #endif /* #if !UCONFIG_NO_FORMATTING */