Merge branch 'main' into feature/trim(29)

Author: dom-baur

CHANGELOG.md

@@ -11,6 +11,13 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - `ltrim`, `rtrim` and `trim` string type utility functions
 
+## [2.1.0] - 2025-09-03
+
+### Added
+
+- `isValidSwissIbanNumber` string utility function
+- `isValidSwissSocialSecurityNumber` string utility function
+
 ## [2.0.0] - 2025-07-29
 
 ### Added
@@ -169,7 +176,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - added `eslint-plugin-jsdoc` to lint jsdoc comments
 - `getEnumNameFromValue`,`getEnumValueFromName`, `getEnumNames`,`getEnumNameValues` functions to respectively get the name of an enum from its value, the value from its name, all the names and all the values
 
-[unreleased]: https://github.com/neolution-ch/javascript-utils/compare/2.0.0...HEAD
+[unreleased]: https://github.com/neolution-ch/javascript-utils/compare/2.1.0...HEAD
+[2.1.0]: https://github.com/neolution-ch/javascript-utils/compare/2.0.0...2.1.0
 [2.0.0]: https://github.com/neolution-ch/javascript-utils/compare/1.5.0...2.0.0
 [1.5.0]: https://github.com/neolution-ch/javascript-utils/compare/1.4.0...1.5.0
 [1.4.0]: https://github.com/neolution-ch/javascript-utils/compare/1.3.1...1.4.0

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@neolution-ch/javascript-utils",
-  "version": "2.0.0",
+  "version": "2.1.0",
   "description": "This is a collection of utilities that we have created to help with our development process.",
   "homepage": "https://neolution-ch.github.io/javascript-utils",
   "repository": {

src/lib/string.spec.ts

@@ -1,4 +1,12 @@
-import { isNullOrEmpty, isNullOrWhitespace, capitalize, uncapitalize, truncate, ltrim, rtrim, trim } from "./string";
+import {
+  isNullOrEmpty,
+  isNullOrWhitespace,
+  capitalize,
+  uncapitalize,
+  truncate,
+  isValidSwissIbanNumber,
+  isValidSwissSocialSecurityNumber,
+} from "./string";
 
 describe("string tests", () => {
   test.each([
@@ -149,4 +157,32 @@ describe("string tests", () => {
   ])("trim", (haystack, needle, expected) => {
     expect(trim(haystack, needle)).toBe(expected);
   });
+    
+    [null as unknown as string, false],
+    [undefined as unknown as string, false],
+    ["CH9300762011623852957", true],
+    ["CH93 0076 2011 6238 5295 7", true],
+    ["CH930076 20116238 5295 7", false],
+    ["CH93-0076-2011-6238-5295-7", false],
+    ["CH93 0000 0000 0000 0000 1", false],
+    ["ch93 0076 2011 6238 5295 7", false],
+    ["DE93 0076 2011 6238 5295 7", false],
+  ])("check if this swiss IBAN is valid or not", (unformattedIbanNumber, expected) => {
+    expect(isValidSwissIbanNumber(unformattedIbanNumber)).toBe(expected);
+  });
+
+  test.each([
+    [null as unknown as string, false],
+    [undefined as unknown as string, false],
+    ["7561234567891", false],
+    ["7569217076985", true],
+    ["756.92170769.85", false],
+    ["756.9217.0769.85", true],
+    ["756..9217.0769.85", false],
+    ["756.1234.5678.91", false],
+    ["test756.9217.0769.85", false],
+    ["7.56..9217...0769.85", false],
+  ])("check if the social insurance number is valid or not", (ahvNumber, expected) => {
+    expect(isValidSwissSocialSecurityNumber(ahvNumber)).toBe(expected);
+  });
 });

src/lib/string.ts

@@ -127,3 +127,111 @@ export function trim(haystack: string, needle: string): string {
   const trimmed = ltrim(haystack, needle);
   return rtrim(trimmed, needle);
 }
+
+/**
+ * Checks if the provided string is a valid swiss IBAN number
+ * @param ibanNumber The provided IBAN number to check
+ * Must be in one of the following formats:
+ * - "CHXX XXXX XXXX XXXX XXXX X" with whitespaces
+ * - "CHXXXXXXXXXXXXXXXXXXX" without whitespaces
+ * @returns The result of the IBAN number check
+ */
+export function isValidSwissIbanNumber(ibanNumber: string): boolean {
+  // 1. Reject null, undefined or whitespace-only strings
+  if (isNullOrWhitespace(ibanNumber)) {
+    return false;
+  }
+
+  // 2. Define allowed strict formats
+  //    - with spaces: "CHXX XXXX XXXX XXXX XXXX X"
+  const compactIbanNumberWithWhiteSpaces = new RegExp(/^CH\d{2}(?: \d{4}){4} \d{1}$/);
+  //    - without spaces: "CHXXXXXXXXXXXXXXXXXXX"
+  const compactIbanNumberWithoutWhiteSpaces = new RegExp(/^CH\d{19}$/);
+
+  // 3. Check if input matches one of the allowed formats
+  if (!compactIbanNumberWithWhiteSpaces.test(ibanNumber) && !compactIbanNumberWithoutWhiteSpaces.test(ibanNumber)) {
+    return false;
+  }
+
+  // 4. Remove all spaces to get a compact IBAN string
+  const compactIbanNumber = ibanNumber.replaceAll(" ", "");
+
+  // 5. Rearrange IBAN for checksum calculation
+  //    - move first 4 characters (CH + 2 check digits) to the end
+  const rearrangedIban = compactIbanNumber.slice(4) + compactIbanNumber.slice(0, 4);
+
+  // 6. Replace letters with numbers (A=10, B=11, ..., Z=35)
+  const numericStr = rearrangedIban.replaceAll(/[A-Z]/g, (ch) => (ch.codePointAt(0)! - 55).toString());
+
+  // 7. Perform modulo 97 calculation to validate IBAN
+  let restOfCalculation = 0;
+  for (const digit of numericStr) {
+    restOfCalculation = (restOfCalculation * 10 + Number(digit)) % 97;
+  }
+
+  // 8. IBAN is valid only if the remainder equals 1
+  return restOfCalculation === 1;
+}
+
+/**
+ * Validation of social insurance number with checking the checksum
+ * Validation according to https://www.sozialversicherungsnummer.ch/aufbau-neu.htm
+ * @param socialInsuranceNumber The social insurance number to check
+ * Must be in one of the following formats:
+ * - "756.XXXX.XXXX.XX" with dots as separators
+ * - "756XXXXXXXXXX" with digits only
+ * @returns The result if the social insurance number is valid or not
+ */
+export function isValidSwissSocialSecurityNumber(socialInsuranceNumber: string): boolean {
+  // 1. Check if input is empty or only whitespace
+  if (isNullOrWhitespace(socialInsuranceNumber)) {
+    return false;
+  }
+
+  /**
+   * 2. Check if input matches accepted formats:
+   *    - With dots: 756.XXXX.XXXX.XX
+   *    - Without dots: 756XXXXXXXXXX
+   */
+  const socialInsuranceNumberWithDots = new RegExp(/^756\.\d{4}\.\d{4}\.\d{2}$/);
+  const socialInsuranceNumberWithoutDots = new RegExp(/^756\d{10}$/);
+
+  if (!socialInsuranceNumberWithDots.test(socialInsuranceNumber) && !socialInsuranceNumberWithoutDots.test(socialInsuranceNumber)) {
+    return false;
+  }
+
+  // 3. Remove all dots → get a string of 13 digits
+  const compactNumber = socialInsuranceNumber.replaceAll(".", "");
+
+  /**
+   * 4. Separate digits for checksum calculation
+   *    - first 12 digits: used to calculate checksum
+   *    - last digit: actual check digit
+   */
+  const digits = compactNumber.slice(0, -1);
+  const reversedDigits = [...digits].reverse().join("");
+  const reversedDigitsArray = [...reversedDigits];
+
+  /*
+   * 5. Calculate weighted sum for checksum
+   *    - Even positions (after reversing) ×3
+   *    - Odd positions ×1
+   */
+  let sum = 0;
+  for (const [i, element] of reversedDigitsArray.entries()) {
+    sum += i % 2 === 0 ? Number(element) * 3 : Number(element) * 1;
+  }
+
+  /*
+   * 6. Calculate expected check digit
+   *    - Check digit = value to reach next multiple of 10
+   */
+  const checksum = (10 - (sum % 10)) % 10;
+  const checknumber = Number.parseInt(compactNumber.slice(-1));
+
+  /*
+   * 7. Compare calculated check digit with actual last digit
+   *    - If equal → valid AHV number
+   */
+  return checksum === checknumber;
+}