ICU-22692 Change SimpleNumber truncateAt to setMaximumIntegerDigits

Also promotes the remaining draft SimpleNumber functions to stable.

See #2892

icu4c/source/i18n/number_capi.cpp

@@ -309,12 +309,17 @@ usnum_setMinimumFractionDigits(USimpleNumber* unumber, int32_t minimumFractionDi
 }
 
 U_CAPI void U_EXPORT2
-usnum_truncateStart(USimpleNumber* unumber, int32_t maximumIntegerDigits, UErrorCode* ec) {
+usnum_setMaximumIntegerDigits(USimpleNumber* unumber, int32_t maximumIntegerDigits, UErrorCode* ec) {
  auto* number = USimpleNumberData::validate(unumber, *ec);
  if (U_FAILURE(*ec)) {
  return;
  }
- number->fNumber.truncateStart(maximumIntegerDigits, *ec);
+ number->fNumber.setMaximumIntegerDigits(maximumIntegerDigits, *ec);
+}
+
+U_CAPI void U_EXPORT2
+usnum_truncateStart(USimpleNumber* unumber, int32_t maximumIntegerDigits, UErrorCode* ec) {
+ usnum_setMaximumIntegerDigits(unumber, maximumIntegerDigits, ec);
 }
 
 U_CAPI void U_EXPORT2

icu4c/source/i18n/number_decimalquantity.cpp

@@ -131,18 +131,24 @@ void DecimalQuantity::clear() {
  setBcdToZero(); // sets scale, precision, hasDouble, origDouble, origDelta, and BCD data
 }
 
-void DecimalQuantity::setMinInteger(int32_t minInt) {
+void DecimalQuantity::decreaseMinIntegerTo(int32_t minInt) {
+ // Validation should happen outside of DecimalQuantity, e.g., in the Precision class.
+ U_ASSERT(minInt >= 0);
+
+ if (lReqPos > minInt) {
+ lReqPos = minInt;
+ }
+}
+
+void DecimalQuantity::increaseMinIntegerTo(int32_t minInt) {
  // Validation should happen outside of DecimalQuantity, e.g., in the Precision class.
  U_ASSERT(minInt >= 0);
 
  // Special behavior: do not set minInt to be less than what is already set.
  // This is so significant digits rounding can set the integer length.
- if (minInt < lReqPos) {
- minInt = lReqPos;
+ if (lReqPos < minInt) {
+ lReqPos = minInt;
  }
-
- // Save values into internal state
- lReqPos = minInt;
 }
 
 void DecimalQuantity::setMinFraction(int32_t minFrac) {

icu4c/source/i18n/number_decimalquantity.h

@@ -52,13 +52,21 @@ class U_I18N_API DecimalQuantity : public IFixedDecimal, public UMemory {
  /** Move assignment */
  DecimalQuantity &operator=(DecimalQuantity&& src) noexcept;
 
+ /**
+ * If the minimum integer digits are greater than `minInt`,
+ * sets it to `minInt`.
+ *
+ * @param minInt The minimum number of integer digits.
+ */
+ void decreaseMinIntegerTo(int32_t minInt);
+
  /**
  * Sets the minimum integer digits that this {@link DecimalQuantity} should generate.
  * This method does not perform rounding.
  *
  * @param minInt The minimum number of integer digits.
  */
- void setMinInteger(int32_t minInt);
+ void increaseMinIntegerTo(int32_t minInt);
 
  /**
  * Sets the minimum fraction digits that this {@link DecimalQuantity} should generate.

icu4c/source/i18n/number_integerwidth.cpp

@@ -46,14 +46,14 @@ void IntegerWidth::apply(impl::DecimalQuantity& quantity, UErrorCode& status) co
  if (fHasError) {
  status = U_ILLEGAL_ARGUMENT_ERROR;
  } else if (fUnion.minMaxInt.fMaxInt == -1) {
- quantity.setMinInteger(fUnion.minMaxInt.fMinInt);
+ quantity.increaseMinIntegerTo(fUnion.minMaxInt.fMinInt);
  } else {
  // Enforce the backwards-compatibility feature "FormatFailIfMoreThanMaxDigits"
  if (fUnion.minMaxInt.fFormatFailIfMoreThanMaxDigits &&
  fUnion.minMaxInt.fMaxInt < quantity.getMagnitude()) {
  status = U_ILLEGAL_ARGUMENT_ERROR;
  }
- quantity.setMinInteger(fUnion.minMaxInt.fMinInt);
+ quantity.increaseMinIntegerTo(fUnion.minMaxInt.fMinInt);
  quantity.applyMaxInteger(fUnion.minMaxInt.fMaxInt);
  }
 }

icu4c/source/i18n/number_patternstring.cpp

@@ -768,7 +768,7 @@ UnicodeString PatternStringUtils::propertiesToPatternString(const DecimalFormatP
  incrementQuantity.roundToInfinity();
  digitsStringScale = incrementQuantity.getLowerDisplayMagnitude();
  incrementQuantity.adjustMagnitude(-digitsStringScale);
- incrementQuantity.setMinInteger(minInt - digitsStringScale);
+ incrementQuantity.increaseMinIntegerTo(minInt - digitsStringScale);
  UnicodeString str = incrementQuantity.toPlainString();
  if (str.charAt(0) == u'-') {
  // TODO: Unsupported operation exception or fail silently?

icu4c/source/i18n/number_rounding.cpp

@@ -437,7 +437,7 @@ void RoundingImpl::apply(impl::DecimalQuantity &value, UErrorCode& status) const
  uprv_max(0, -getDisplayMagnitudeSignificant(value, fPrecision.fUnion.fracSig.fMinSig));
  // Make sure that digits are displayed on zero.
  if (value.isZeroish() && fPrecision.fUnion.fracSig.fMinSig > 0) {
- value.setMinInteger(1);
+ value.increaseMinIntegerTo(1);
  }
  break;
 

icu4c/source/i18n/number_simple.cpp

@@ -81,7 +81,8 @@ void SimpleNumber::setMinimumIntegerDigits(uint32_t position, UErrorCode& status
  status = U_INVALID_STATE_ERROR;
  return;
  }
- fData->quantity.setMinInteger(position);
+ fData->quantity.decreaseMinIntegerTo(position);
+ fData->quantity.increaseMinIntegerTo(position);
 }
 
 void SimpleNumber::setMinimumFractionDigits(uint32_t position, UErrorCode& status) {
@@ -95,17 +96,22 @@ void SimpleNumber::setMinimumFractionDigits(uint32_t position, UErrorCode& statu
  fData->quantity.setMinFraction(position);
 }
 
-void SimpleNumber::truncateStart(uint32_t position, UErrorCode& status) {
+void SimpleNumber::setMaximumIntegerDigits(uint32_t position, UErrorCode& status) {
  if (U_FAILURE(status)) {
  return;
  }
  if (fData == nullptr) {
  status = U_INVALID_STATE_ERROR;
  return;
  }
+ fData->quantity.decreaseMinIntegerTo(position);
  fData->quantity.applyMaxInteger(position);
 }
 
+void SimpleNumber::truncateStart(uint32_t position, UErrorCode& status) {
+ setMaximumIntegerDigits(position, status);
+}
+
 void SimpleNumber::setSign(USimpleNumberSign sign, UErrorCode& status) {
  if (U_FAILURE(status)) {
  return;

icu4c/source/i18n/smpdtfmt.cpp

@@ -2164,7 +2164,7 @@ SimpleDateFormat::zeroPaddingNumber(
  data.quantity.setToLong(value);
  number::SimpleNumber number(&data, localStatus);
  number.setMinimumIntegerDigits(minDigits, localStatus);
- number.truncateStart(maxDigits, localStatus);
+ number.setMaximumIntegerDigits(maxDigits, localStatus);
 
  number::FormattedNumber result = fSimpleNumberFormatter->format(std::move(number), localStatus);
  if (U_FAILURE(localStatus)) {

icu4c/source/i18n/unicode/simplenumberformatter.h

@@ -68,44 +68,49 @@ class U_I18N_API SimpleNumber : public UMemory {
  */
  void multiplyByPowerOfTen(int32_t power, UErrorCode& status);
 
-#ifndef U_HIDE_DRAFT_API
  /**
- * Rounds the value currently stored in the SimpleNumber to the given power of 10.
+ * Rounds the value currently stored in the SimpleNumber to the given power of 10,
+ * which can be before or after the decimal separator.
  *
- * This function immediately mutates the inner value.
+ * This function does not change minimum integer digits.
  *
- * @draft ICU 73
+ * @stable ICU 73
  */
  void roundTo(int32_t power, UNumberFormatRoundingMode roundingMode, UErrorCode& status);
 
+#ifndef U_HIDE_DRAFT_API
  /**
- * Truncates the most significant digits to the given maximum number of integer digits.
+ * Sets the number of integer digits to the given amount, truncating if necessary.
  *
- * This function immediately mutates the inner value.
+ * @draft ICU 75
+ */
+ void setMaximumIntegerDigits(uint32_t maximumIntegerDigits, UErrorCode& status);
+#endif // U_HIDE_DRAFT_API
+
+#ifndef U_HIDE_DEPRECATED_API
+ /**
+ * Alias for setMaximumIntegerDigits.
+ * Will be removed after ICU 75.
  *
- * @draft ICU 73
+ * @deprecated ICU 75
  */
  void truncateStart(uint32_t maximumIntegerDigits, UErrorCode& status);
+#endif // U_HIDE_DEPRECATED_API
 
  /**
  * Pads the beginning of the number with zeros up to the given minimum number of integer digits.
  *
- * This setting is applied upon formatting the number. 
- *
- * @draft ICU 73
+ * @stable ICU 73
  */
  void setMinimumIntegerDigits(uint32_t minimumIntegerDigits, UErrorCode& status);
 
  /**
  * Pads the end of the number with zeros up to the given minimum number of fraction digits.
  *
- * This setting is applied upon formatting the number.
- *
- * @draft ICU 73
+ * @stable ICU 73
  */
  void setMinimumFractionDigits(uint32_t minimumFractionDigits, UErrorCode& status);
 
-#endif // U_HIDE_DRAFT_API
  /**
  * Sets the sign of the number: an explicit plus sign, explicit minus sign, or no sign.
  *

icu4c/source/i18n/unicode/usimplenumberformatter.h

@@ -126,13 +126,13 @@ U_CAPI void U_EXPORT2
 usnum_multiplyByPowerOfTen(USimpleNumber* unumber, int32_t power, UErrorCode* ec);
 
 
-#ifndef U_HIDE_DRAFT_API
 /**
- * Rounds the value currently stored in the USimpleNumber to the given power of 10.
+ * Rounds the value currently stored in the USimpleNumber to the given power of 10,
+ * which can be before or after the decimal separator.
  *
- * This function immediately mutates the inner value.
+ * This function does not change minimum integer digits.
  *
- * @draft ICU 73
+ * @stable ICU 73
  */
 U_CAPI void U_EXPORT2
 usnum_roundTo(USimpleNumber* unumber, int32_t power, UNumberFormatRoundingMode roundingMode, UErrorCode* ec);
@@ -141,9 +141,7 @@ usnum_roundTo(USimpleNumber* unumber, int32_t power, UNumberFormatRoundingMode r
 /**
  * Pads the beginning of the number with zeros up to the given minimum number of integer digits.
  *
- * This setting is applied upon formatting the number.
- *
- * @draft ICU 73
+ * @stable ICU 73
  */
 U_CAPI void U_EXPORT2
 usnum_setMinimumIntegerDigits(USimpleNumber* unumber, int32_t minimumIntegerDigits, UErrorCode* ec);
@@ -152,25 +150,34 @@ usnum_setMinimumIntegerDigits(USimpleNumber* unumber, int32_t minimumIntegerDigi
 /**
  * Pads the end of the number with zeros up to the given minimum number of fraction digits.
  *
- * This setting is applied upon formatting the number.
- *
- * @draft ICU 73
+ * @stable ICU 73
  */
 U_CAPI void U_EXPORT2
 usnum_setMinimumFractionDigits(USimpleNumber* unumber, int32_t minimumFractionDigits, UErrorCode* ec);
 
 
+#ifndef U_HIDE_DRAFT_API
 /**
- * Truncates digits from the beginning of the number to the given maximum number of integer digits.
+ * Sets the number of integer digits to the given amount, truncating if necessary.
  *
- * This function immediately mutates the inner value.
+ * @draft ICU 75
+ */
+U_CAPI void U_EXPORT2
+usnum_setMaximumIntegerDigits(USimpleNumber* unumber, int32_t maximumIntegerDigits, UErrorCode* ec);
+#endif // U_HIDE_DRAFT_API
+
+
+#ifndef U_HIDE_DEPRECATED_API
+/**
+ * Alias for setMaximumIntegerDigits.
+ * Will be removed after ICU 75.
  *
- * @draft ICU 73
+ * @deprecated ICU 75
  */
 U_CAPI void U_EXPORT2
 usnum_truncateStart(USimpleNumber* unumber, int32_t maximumIntegerDigits, UErrorCode* ec);
+#endif // U_HIDE_DEPRECATED_API
 
-#endif // U_HIDE_DRAFT_API
 
 /**
  * Sets the sign of the number: an explicit plus sign, explicit minus sign, or no sign.

icu4c/source/test/cintltst/unumberformattertst.c

@@ -255,9 +255,9 @@ static void TestSimpleNumberFormatterFull(void) {
  usnum_setToInt64(unumber, 98765, &ec);
  usnum_multiplyByPowerOfTen(unumber, -2, &ec);
  usnum_roundTo(unumber, -1, UNUM_ROUND_HALFDOWN, &ec);
+ usnum_setMaximumIntegerDigits(unumber, 1, &ec);
  usnum_setMinimumIntegerDigits(unumber, 4, &ec);
  usnum_setMinimumFractionDigits(unumber, 3, &ec);
- usnum_truncateStart(unumber, 1, &ec);
  usnum_setSign(unumber, UNUM_SIMPLE_NUMBER_PLUS_SIGN, &ec);
 
  usnumf_format(uformatter, unumber, uresult, &ec);

icu4c/source/test/intltest/numbertest.h

@@ -373,6 +373,7 @@ class SimpleNumberFormatterTest : public IntlTestWithFieldPosition {
  public:
  void testBasic();
  void testWithOptions();
+ void testDigits();
  void testSymbols();
  void testSign();
  void testCopyMove();

icu4c/source/test/intltest/numbertest_decimalquantity.cpp

@@ -92,7 +92,7 @@ void DecimalQuantityTest::testDecimalQuantityBehaviorStandalone() {
 
  fq.setToLong(90909090909000L);
  assertToStringAndHealth(fq, u"<DecimalQuantity 0:0 long 90909090909E3>");
- fq.setMinInteger(2);
+ fq.increaseMinIntegerTo(2);
  fq.applyMaxInteger(5);
  assertToStringAndHealth(fq, u"<DecimalQuantity 2:0 long 9E3>");
  fq.setMinFraction(3);
@@ -424,7 +424,7 @@ void DecimalQuantityTest::testMaxDigits() {
  DecimalQuantity dq;
  dq.setToDouble(876.543);
  dq.roundToInfinity();
- dq.setMinInteger(0);
+ dq.increaseMinIntegerTo(0);
  dq.applyMaxInteger(2);
  dq.setMinFraction(0);
  dq.roundToMagnitude(-2, UNUM_ROUND_FLOOR, status);