feat: improve useNetworkState tests

src/useNetworkState.ts

@@ -117,6 +117,8 @@ export const useNetworkState: typeof navigator.connection extends undefined
         on(window, 'online', handleStateChange, { passive: true });
         on(window, 'offline', handleStateChange, { passive: true });
 
+        // it is quite hard to test it in jsdom environment maybe will be improved in future
+        /* istanbul ignore next */
         if (conn) {
           on(conn, 'change', handleStateChange, { passive: true });
         }
@@ -125,6 +127,7 @@ export const useNetworkState: typeof navigator.connection extends undefined
           off(window, 'online', handleStateChange);
           off(window, 'offline', handleStateChange);
 
+          /* istanbul ignore next */
           if (conn) {
             off(conn, 'change', handleStateChange);
           }

tests/dom/useNetworkState.test.ts

@@ -1,4 +1,5 @@
-import { renderHook } from '@testing-library/react-hooks/dom';
+import { act, renderHook } from '@testing-library/react-hooks/dom';
+import { useRef } from 'react';
 import { useNetworkState } from '../../src/useNetworkState';
 
 describe(`useNetworkState`, () => {
@@ -25,4 +26,23 @@ describe(`useNetworkState`, () => {
       'type',
     ]);
   });
+
+  it('should rerender in case of online or offline events emitted on window', () => {
+    const hook = renderHook(
+      () => {
+        const renderCount = useRef(0);
+        return [useNetworkState(), ++renderCount.current];
+      },
+      { initialProps: false }
+    );
+
+    expect(hook.result.current[1]).toBe(1);
+    const prevNWState = hook.result.current[0];
+
+    act(() => {
+      window.dispatchEvent(new Event('online'));
+    });
+    expect(hook.result.current[1]).toBe(2);
+    expect(hook.result.current[0]).not.toBe(prevNWState);
+  });
 });