test[faustwp-core]: (#1940) add test coverage for sitemapIndexPath option (#2321)

* test[faustwp-core]: (#1940) add test coverage for sitemapIndexPath option

Add three tests to createSitemaps.test.ts verifying sitemapIndexPath
behavior in createRootSitemapIndex():

- Fetches from custom sitemapIndexPath when provided
- Falls back to default /sitemap.xml when not provided
- Trims leading/trailing slashes from sitemapIndexPath

Closes #1940

* chore: add changeset for sitemapIndexPath test coverage

* test[faustwp-core]: prettier formatting

---------

Co-authored-by: latenighthackathon <latenighthackathon@users.noreply.github.com>

Author: latenighthackathon

.changeset/sitemap-index-path-tests.md

@@ -0,0 +1,5 @@
+---
+"@faustwp/core": patch
+---
+
+test[faustwp-core]: add test coverage for sitemapIndexPath option in createRootSitemapIndex

packages/faustwp-core/tests/server/sitemaps/createSitemaps.test.ts

@@ -242,6 +242,82 @@ describe('createRootSitemapIndex', () => {
 
 		expect(createSitemapIndexSpy).toHaveBeenCalledWith(expectedSitemaps);
 	});
+
+	it('fetches from custom sitemapIndexPath when provided', async () => {
+		const fetchSpy = jest
+			.spyOn(global, 'fetch')
+			.mockImplementationOnce((url) => {
+				// Verify the custom path was used in the fetch URL
+				expect(url).toBe('http://headless.local/custom-sitemap-index.xml');
+				return Promise.resolve({
+					ok: true,
+					status: 200,
+					text: () => Promise.resolve(validSitemapIndex1RecordXML),
+				}) as Promise<Response>;
+			});
+
+		const req = {
+			url: 'http://localhost:3000/sitemap.xml',
+		} as NextRequest;
+
+		const config: GetSitemapPropsConfig = {
+			frontendUrl: 'http://localhost:3000',
+			sitemapIndexPath: '/custom-sitemap-index.xml',
+		};
+
+		await createSitemaps.createRootSitemapIndex(req, config);
+
+		expect(fetchSpy).toHaveBeenCalledWith(
+			'http://headless.local/custom-sitemap-index.xml',
+		);
+	});
+
+	it('fetches from default /sitemap.xml when sitemapIndexPath is not provided', async () => {
+		const fetchSpy = jest.spyOn(global, 'fetch').mockImplementationOnce(() => {
+			return Promise.resolve({
+				ok: true,
+				status: 200,
+				text: () => Promise.resolve(validSitemapIndex1RecordXML),
+			}) as Promise<Response>;
+		});
+
+		const req = {
+			url: 'http://localhost:3000/sitemap.xml',
+		} as NextRequest;
+
+		const config: GetSitemapPropsConfig = {
+			frontendUrl: 'http://localhost:3000',
+		};
+
+		await createSitemaps.createRootSitemapIndex(req, config);
+
+		expect(fetchSpy).toHaveBeenCalledWith('http://headless.local/sitemap.xml');
+	});
+
+	it('trims slashes from sitemapIndexPath', async () => {
+		const fetchSpy = jest.spyOn(global, 'fetch').mockImplementationOnce(() => {
+			return Promise.resolve({
+				ok: true,
+				status: 200,
+				text: () => Promise.resolve(validSitemapIndex1RecordXML),
+			}) as Promise<Response>;
+		});
+
+		const req = {
+			url: 'http://localhost:3000/sitemap.xml',
+		} as NextRequest;
+
+		const config: GetSitemapPropsConfig = {
+			frontendUrl: 'http://localhost:3000',
+			sitemapIndexPath: '/yoast-sitemap.xml/',
+		};
+
+		await createSitemaps.createRootSitemapIndex(req, config);
+
+		expect(fetchSpy).toHaveBeenCalledWith(
+			'http://headless.local/yoast-sitemap.xml',
+		);
+	});
 });
 
 describe('createPagesSitemap()', () => {