Extend test cases for the router value memoization

Author: ostapch

packages/wouter/src/index.js

@@ -180,7 +180,7 @@ export const Router = ({ children, ...props }) => {
 
     next[k] = option;
 
-    // the new router is no different from the parent, use parent
+    // the new router is no different from the parent or from the memoized value, use parent
     if (option !== parent[k] || option !== value[k]) value = next;
   }
 

packages/wouter/test/router.test.tsx

@@ -243,4 +243,22 @@ it("updates the context when settings are changed", () => {
   expect(state.renders).toEqual(2);
   expect(state.base).toEqual("/app");
   expect(state.hook).toEqual(newHook);
+
+  // should update the context when the base changes as well
+  rerender(
+    <Router hook={newHook} base="">
+      <Memoized />
+    </Router>
+  );
+  expect(state.renders).toEqual(3);
+  expect(state.base).toEqual("");
+  expect(state.hook).toEqual(newHook);
+
+  // the last check that the router context is stable during re-renders
+  rerender(
+    <Router hook={newHook} base="">
+      <Memoized />
+    </Router>
+  );
+  expect(state.renders).toEqual(3); // nothing changed
 });