feat: enhance currency formatting with trailing zero omission

src/exports.test.ts

@@ -6,6 +6,7 @@ const expectedNamedExports = [
   'formatAmount',
   'formatAmountFromString',
   'formatPriceUnit',
+  'omitTrailingDecimalZeros',
   'parseDecimalValue',
   'toDinero',
   'toDineroFromInteger',

src/index.ts

@@ -3,6 +3,7 @@ export {
   formatAmount,
   formatAmountFromString,
   formatPriceUnit,
+  omitTrailingDecimalZeros,
   parseDecimalValue,
   toIntegerAmount,
   addSeparatorToDineroString,

src/money/formatters.test.ts

@@ -5,6 +5,7 @@ import {
   formatAmount,
   formatAmountFromString,
   formatPriceUnit,
+  omitTrailingDecimalZeros,
   parseDecimalValue,
   toIntegerAmount,
   unitDisplayLabels,
@@ -294,6 +295,26 @@ describe('formatPriceUnit', () => {
   );
 });
 
+describe('omitTrailingDecimalZeros', () => {
+  it.each`
+    price                | expected
+    ${'10.00 €'}         | ${'10 €'}
+    ${'10,00 €'}         | ${'10 €'}
+    ${'1.000,00 €'}      | ${'1.000 €'}
+    ${'10.50 €'}         | ${'10.50 €'}
+    ${'10,50 €'}         | ${'10,50 €'}
+    ${'€10.00'}          | ${'€10'}
+    ${'€10.00/Stück'}    | ${'€10/Stück'}
+    ${'€10,00/Stück'}    | ${'€10/Stück'}
+    ${'10.00 € / Monat'} | ${'10 € / Monat'}
+    ${'10,00 € / Monat'} | ${'10 € / Monat'}
+    ${'0.00 €'}          | ${'0 €'}
+    ${'10.20 €'}         | ${'10.20 €'}
+  `('should transform "$price" into "$expected"', ({ price, expected }) => {
+    expect(omitTrailingDecimalZeros(price)).toEqual(expected);
+  });
+});
+
 describe('parseDecimalValue', () => {
   it.each`
     value                | expected

src/money/formatters.ts

@@ -217,14 +217,9 @@ export const formatAmountFromString = ({
       subunitFromAmount,
     );
 
-    return formatWithSubunit(
-      dineroObjectFromAmount
-        .multiply(100)
-        .convertPrecision(precision ?? amountPrecision)
-        .setLocale(locale || DEFAULT_LOCALE)
-        .toFormat(format || amountFormat),
-      subunit,
-    );
+    const dSubunit = dineroObjectFromAmount.multiply(100).convertPrecision(precision ?? amountPrecision);
+
+    return formatWithSubunit(dSubunit.setLocale(locale || DEFAULT_LOCALE).toFormat(format || amountFormat), subunit);
   }
 
   return dineroObjectFromAmount
@@ -352,6 +347,26 @@ function shouldDisplayAmountAsCents(amount: number, currency?: Currency) {
   return dAbsoluteAmount.hasSubUnits() && dAbsoluteAmount.lessThan(dAmountOfOneUnit);
 }
 
+/**
+ * Removes trailing decimal zeros (.00 or ,00) from a formatted price string.
+ * Handles prices with currency symbols, billing period suffixes, and tiered pricing unit suffixes (e.g. €10.00/Stück).
+ *
+ * @param price - The formatted price string
+ * @returns The price string without trailing decimal zeros
+ */
+export const omitTrailingDecimalZeros = (price: string): string => {
+  const trailingZerosWithDot = /(\.00)(\s.*)?$/;
+  const trailingZerosWithComma = /(,00)(\s.*)?$/;
+  const trailingZerosWithDotBeforeSlash = /(\.00)(\/[\w\W]*)$/;
+  const trailingZerosWithCommaBeforeSlash = /(,00)(\/[\w\W]*)$/;
+
+  return price
+    .replace(trailingZerosWithDot, '$2')
+    .replace(trailingZerosWithComma, '$2')
+    .replace(trailingZerosWithDotBeforeSlash, '$2')
+    .replace(trailingZerosWithCommaBeforeSlash, '$2');
+};
+
 /**
  * Converts a decimal string value into a valid decimal amount value, without any thousand separators, using dot as the decimal separator.
  *