Enhance appendLine method to handle empty input and add newlines accordingly

Author: electricessence

dist/cjs/StringBuilder.js

@@ -67,7 +67,8 @@ export default class StringBuilder
 	}
 
 	appendLine(...items: any[]): this {
-		this.appendLines(items);
+		if(items?.length) this.appendLines(items);
+		else this._partArray.push(this.newLine);
 		return this;
 	}
 

dist/cjs/StringBuilder.js.map

@@ -119,6 +119,33 @@ describe('StringBuilder', () => {
 			sb.appendLines(['first', 'second']);
 			expect(sb.toString()).toBe('first\nsecond\n');
 		});
+
+		it('should add newline when appendLine called with no parameters', () => {
+			const sb = new StringBuilder();
+			sb.append('content');
+			sb.appendLine(); // No parameters
+			sb.append('more');
+			expect(sb.toString()).toBe('content\nmore');
+			expect(sb.toString()).toContain('\n');
+		});
+
+		it('should add multiple newlines when appendLine called multiple times with no parameters', () => {
+			const sb = new StringBuilder();
+			sb.append('line1');
+			sb.appendLine(); // First newline
+			sb.appendLine(); // Second newline (empty line)
+			sb.append('line2');
+			expect(sb.toString()).toBe('line1\n\nline2');
+		});
+
+		it('should use custom newline when appendLine called with no parameters', () => {
+			const sb = new StringBuilder();
+			sb.setNewLine('\r\n');
+			sb.append('content');
+			sb.appendLine(); // Should use \r\n
+			sb.append('more');
+			expect(sb.toString()).toBe('content\r\nmore');
+		});
 	});
 
 	describe('newLine handling', () => {