Fixed return type on getRows (#1564)

pmcilwaine · web-flow · commit 410b1bea60f5 · 2021-02-14T20:05:42.000+01:00
diff --git a/index.d.ts b/index.d.ts
@@ -1244,7 +1244,7 @@ export interface Worksheet {
 	/**
 	 * Get or create rows by 1-based index
 	 */
-	getRows(start: number, length: number): Row[];
+	getRows(start: number, length: number): Row[] | undefined;
 
 	/**
 	 * Iterate over all rows that have values in a worksheet
diff --git a/spec/integration/worksheet.spec.js b/spec/integration/worksheet.spec.js
@@ -639,6 +639,13 @@ describe('Worksheet', () => {
       expect(count).to.equal(7);
     });
 
+    it('returns undefined when row range is less than 1', () => {
+      const wb = new ExcelJS.Workbook();
+      const ws = wb.addWorksheet('blort');
+
+      expect(ws.getRows(1, 0)).to.equal(undefined);
+    });
+
     context('when worksheet name is less than or equal 31', () => {
       it('save the original name', () => {
         const wb = new ExcelJS.Workbook();
