Add string utility functions: splitLines

CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+
+- `splitLine` string utility function
+
 ## [2.0.0] - 2025-07-29
 
 ### Added

src/lib/string.spec.ts

@@ -1,4 +1,4 @@
-import { isNullOrEmpty, isNullOrWhitespace, capitalize, uncapitalize, truncate } from "./string";
+import { isNullOrEmpty, isNullOrWhitespace, capitalize, uncapitalize, truncate, splitLine } from "./string";
 
 describe("string tests", () => {
   test.each([
@@ -120,4 +120,33 @@ describe("string tests", () => {
   ])("truncate without suffix parameter", (value, maxLength, expected) => {
     expect(truncate(value, maxLength)).toBe(expected);
   });
+
+  test.each([["hello world", ["hello world"]]])("splitLine with single line", (str, expected) => {
+    expect(splitLine(str)).toStrictEqual(expected);
+  });
+
+  test.each([
+    ["hello world", ["hello world"]],
+    ["hello world\nhello world\nhello world", ["hello world", "hello world", "hello world"]],
+    ["hello world\rhello world\rhello world", ["hello world", "hello world", "hello world"]],
+    ["hello world\r\nhello world\r\nhello world", ["hello world", "hello world", "hello world"]],
+  ])("splitLine", (str, expected) => {
+    expect(splitLine(str)).toStrictEqual(expected);
+  });
+
+  test.each([
+    ["", []],
+    [null as unknown as string, []],
+    [undefined as unknown as string, []],
+  ])("splitLine with empty strings", (str, expected) => {
+    expect(splitLine(str)).toStrictEqual(expected);
+  });
+
+  test.each([
+    [null as unknown as string, []],
+    [undefined as unknown as string, []],
+    ["hello world\n", ["hello world"]],
+  ])("splitLine with the option to remove empty entries", (str, expected) => {
+    expect(splitLine(str, true)).toEqual(expected);
+  });
 });

src/lib/string.ts

@@ -64,3 +64,20 @@ export function truncate(value: string | undefined, maxLength: number, suffix =
 
   return `${value.slice(0, maxLength)}${suffix}`;
 }
+
+/**
+ * Splits the string at line breaks
+ * @param str the string to split
+ * @param removeEmptyEntries the option to remove empty entries
+ * @returns the individual lines as an array
+ */
+export function splitLine(str: string, removeEmptyEntries: boolean = false): string[] {
+  if (isNullOrEmpty(str)) {
+    return [];
+  }
+
+  if (removeEmptyEntries) {
+    return str.split(/\r\n|\r|\n/).filter((line) => !isNullOrWhitespace(line));
+  }
+  return str.split(/\r\n|\r|\n/);
+}