Use actual previous context to noop useContextMutator setContext

Signed-off-by: MattIPv4 <[email protected]>

Author: MattIPv4

packages/react/src/context/use-context-mutator.ts

@@ -32,20 +32,19 @@ export type ContextMutation = {
  */
 export function useContextMutator(options: ContextMutationOptions = { defaultContext: false }): ContextMutation {
     const { domain } = useContext(Context) || {};
-    const previousContext = useRef<null | EvaluationContext>(null);
 
     const setContext = useCallback(async (updatedContext: EvaluationContext | ((currentContext: EvaluationContext) => EvaluationContext)): Promise<void> => {
+        const previousContext = OpenFeature.getContext(options?.defaultContext ? undefined : domain);
         const resolvedContext = typeof updatedContext === 'function'
-            ? updatedContext(OpenFeature.getContext(options?.defaultContext ? undefined : domain))
+            ? updatedContext(previousContext)
             : updatedContext;
 
-        if (previousContext.current !== resolvedContext) {
+        if (previousContext !== resolvedContext) {
             if (!domain || options?.defaultContext) {
                 OpenFeature.setContext(resolvedContext);
             } else {
                 OpenFeature.setContext(domain, resolvedContext);
             }
-            previousContext.current = resolvedContext;
         }
     }, [domain, options?.defaultContext]);
 

packages/react/test/provider.spec.tsx

@@ -1,5 +1,5 @@
 import type { EvaluationContext} from '@openfeature/web-sdk';
-import { InMemoryProvider, OpenFeature } from '@openfeature/web-sdk';
+import { InMemoryProvider, OpenFeature, ProviderEvents } from '@openfeature/web-sdk';
 import '@testing-library/jest-dom'; // see: https://testing-library.com/docs/react-testing-library/setup
 import { render, renderHook, screen, waitFor, fireEvent, act } from '@testing-library/react';
 import * as React from 'react';
@@ -310,32 +310,46 @@ describe('OpenFeatureProvider', () => {
       const DOMAIN = 'mutate-context-with-function';
       OpenFeature.setProvider(DOMAIN, suspendingProvider(), { done: false });
 
+      const reconcile = jest.fn();
+      OpenFeature.getClient(DOMAIN).addHandler(ProviderEvents.Reconciling, reconcile);
+
       const setter = jest.fn((prevContext: EvaluationContext) => ({ ...prevContext, user: '[email protected]' }));
       render(
         <OpenFeatureProvider domain={DOMAIN}>
-          <React.Suspense fallback={<div>{FALLBACK}</div>}>
-            <TestComponent name="Will" setter={setter} />
-          </React.Suspense>
+          <MutateButton setter={setter} />
         </OpenFeatureProvider>,
       );
 
-      await waitFor(() => {
-        expect(screen.getByText('Will says hi')).toBeInTheDocument();
-      });
-
       act(() => {
         fireEvent.click(screen.getByText('Update Context'));
       });
-      await waitFor(
-        () => {
-          expect(screen.getByText('Will says aloha')).toBeInTheDocument();
-        },
-        { timeout: DELAY * 4 },
+      expect(setter).toHaveBeenCalledTimes(1);
+      expect(setter).toHaveBeenCalledWith({ done: false });
+      expect(reconcile).toHaveBeenCalledTimes(1);
+      expect(OpenFeature.getContext(DOMAIN)).toEqual({ done: false, user: '[email protected]' });
+    });
+
+    it('should noop if the previous context is passed in unchanged', async () => {
+      const DOMAIN = 'mutate-context-noop';
+      OpenFeature.setProvider(DOMAIN, suspendingProvider(), { done: false });
+
+      const reconcile = jest.fn();
+      OpenFeature.getClient(DOMAIN).addHandler(ProviderEvents.Reconciling, reconcile);
+
+      const setter = jest.fn((prevContext: EvaluationContext) => prevContext);
+      render(
+        <OpenFeatureProvider domain={DOMAIN}>
+          <MutateButton setter={setter} />
+        </OpenFeatureProvider>,
       );
 
+      act(() => {
+        fireEvent.click(screen.getByText('Update Context'));
+      });
       expect(setter).toHaveBeenCalledTimes(1);
       expect(setter).toHaveBeenCalledWith({ done: false });
-      expect(OpenFeature.getContext(DOMAIN)).toEqual({ done: false, user: '[email protected]' });
+      expect(reconcile).toHaveBeenCalledTimes(0);
+      expect(OpenFeature.getContext(DOMAIN)).toEqual({ done: false });
     });
   });
 });