only notify the latest subscriber during client.subscribe

boardgameio · Oct 25, 2019 · 9596fa4 · 9596fa4
1 parent 5a13f00
commit 9596fa4
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Showing 2 changed files with 19 additions and 3 deletions.
diff --git a/src/client/client.js b/src/client/client.js
@@ -352,7 +352,7 @@ class _ClientImpl {
     const id = Object.keys(this.subscribers).length;
     this.subscribers[id] = fn;
     this.transport.subscribe(() => this.notifySubscribers());
-    this.notifySubscribers();
+    fn(this.getState());
 
     // Return a handle that allows the caller to unsubscribe.
     return () => {

diff --git a/src/client/client.test.js b/src/client/client.test.js
@@ -608,6 +608,20 @@ describe('subscribe', () => {
     const fn2 = jest.fn();
     const unsubscribe = client.subscribe(fn2);
 
+    // The subscriber that just subscribed is notified.
+    expect(fn).not.toBeCalled();
+    expect(fn2).toBeCalledWith(
+      expect.objectContaining({
+        G: { moved: true },
+      })
+    );
+
+    fn.mockClear();
+    fn2.mockClear();
+
+    client.moves.A();
+
+    // Both subscribers are notified.
     expect(fn).toBeCalledWith(
       expect.objectContaining({
         G: { moved: true },
@@ -618,11 +632,13 @@ describe('subscribe', () => {
         G: { moved: true },
       })
     );
-    fn.mockClear();
-    fn2.mockClear();
 
     unsubscribe();
 
+    fn.mockClear();
+    fn2.mockClear();
+
+    // The subscriber the unsubscribed is not notified.
     client.moves.A();
     expect(fn).toBeCalledWith(
       expect.objectContaining({