Fix Link doesn't manage search-only to param

Author: fzaninotto

packages/ra-router-tanstack/src/tanStackRouterProvider.spec.tsx

@@ -703,6 +703,41 @@ describe('tanStackRouterProvider', () => {
                 ).toBeInTheDocument();
             });
         });
+
+        it('should support location object with pathname and search', async () => {
+            render(<LinkComponent />);
+            await waitFor(() => {
+                expect(
+                    screen.getByText('Go to Post #4 (with search)')
+                ).toBeInTheDocument();
+            });
+
+            fireEvent.click(screen.getByText('Go to Post #4 (with search)'));
+
+            await waitFor(() => {
+                expect(screen.getByText('Post Details')).toBeInTheDocument();
+            });
+            // Check that search params are preserved in location
+            expect(screen.getByText(/\"search\": \"\?foo=bar\"/)).toBeInTheDocument();
+        });
+
+        it('should support location object with only search (no pathname)', async () => {
+            render(<LinkComponent />);
+            await waitFor(() => {
+                expect(
+                    screen.getByText('Go to same page with search param')
+                ).toBeInTheDocument();
+            });
+
+            fireEvent.click(screen.getByText('Go to same page with search param'));
+
+            await waitFor(() => {
+                // Should stay on the same page (Link Tests page)
+                expect(screen.getByText('Link Component Tests')).toBeInTheDocument();
+            });
+            // Check that search params are added
+            expect(screen.getByText(/\"search\": \"\?foo=bar\"/)).toBeInTheDocument();
+        });
     });
 
     describe('Routes', () => {

packages/ra-router-tanstack/src/tanStackRouterProvider.stories.tsx

@@ -61,6 +61,7 @@ const dataProvider = fakeDataProvider(
             { id: 1, title: 'Post #1', body: 'Hello World' },
             { id: 2, title: 'Post #2', body: 'Second post' },
             { id: 3, title: 'Post #3', body: 'Third post' },
+            { id: 4, title: 'Post #4', body: 'Fourth post' },
         ],
         comments: [
             { id: 1, post_id: 1, body: 'Nice post!' },
@@ -426,8 +427,17 @@ export const LinkComponent = () => {
                     Go to Post #3 (with state)
                 </LinkBase>
 
-                <h3>Current Location State</h3>
-                <pre>{JSON.stringify(location.state, null, 2)}</pre>
+                <h3>Link with Location object</h3>
+                <LinkBase
+                    to={{ pathname: '/posts/4/show', search: '?foo=bar' }}
+                >
+                    Go to Post #4 (with search)
+                </LinkBase>
+
+                <h3>Link with no pathname change</h3>
+                <LinkBase to={{ search: '?foo=bar' }}>
+                    Go to same page with search param
+                </LinkBase>
             </div>
         );
     };

packages/ra-router-tanstack/src/tanStackRouterProvider.tsx

@@ -424,6 +424,7 @@ const useBlocker = (
 const Link = forwardRef<HTMLAnchorElement, RouterLinkProps>(
     ({ to, replace, state, children, ...rest }, ref) => {
         const basename = useBasename();
+        const currentLocation = useTanStackLocation();
 
         // Helper to prepend basename to absolute paths
         const resolvePath = (path: string) => {
@@ -434,12 +435,15 @@ const Link = forwardRef<HTMLAnchorElement, RouterLinkProps>(
             return `${basename}${path}`;
         };
 
-        // Handle object `to` with pathname (e.g., { pathname: '/path', search: '?foo=bar' })
+        // Handle object `to` (e.g., { pathname: '/path', search: '?foo=bar' })
         let resolvedTo: string;
         let resolvedState = state;
-        if (typeof to === 'object' && to !== null && 'pathname' in to) {
+        if (typeof to === 'object' && to !== null) {
             const loc = to as Partial<RouterLocation>;
-            let path = resolvePath(loc.pathname ?? '/');
+            // If no pathname provided, use current pathname to stay on current page
+            let path = loc.pathname
+                ? resolvePath(loc.pathname)
+                : currentLocation.pathname;
             if (loc.search) {
                 path += loc.search.startsWith('?')
                     ? loc.search