[v13] fix watcher setup in oidc test

tool/tsh/tsh_test.go

@@ -365,39 +365,40 @@ func TestOIDCLogin(t *testing.T) {
 	proxyAddr, err := proxyProcess.ProxyWebAddr()
 	require.NoError(t, err)
 
+	// set up watcher to approve the automatic request in background
 	var didAutoRequest atomic.Bool
+	watcher, err := authServer.NewWatcher(ctx, types.Watch{
+		Kinds: []types.WatchKind{
+			{Kind: types.KindAccessRequest},
+		},
+	})
+	require.NoError(t, err)
+
+	// ensure that we observe init event prior to moving watcher to background
+	// goroutine (ensures watcher init does not race with request creation).
+	select {
+	case event := <-watcher.Events():
+		require.Equal(t, event.Type, types.OpInit)
+	case <-watcher.Done():
+		require.FailNow(t, "watcher closed unexpected", "err: %v", watcher.Error())
+	}
 
-	errCh := make(chan error)
 	go func() {
-		watcher, err := authServer.NewWatcher(ctx, types.Watch{
-			Kinds: []types.WatchKind{
-				{Kind: types.KindAccessRequest},
-			},
-		})
-		if err != nil {
-			errCh <- err
-			return
-		}
-		for {
-			select {
-			case event := <-watcher.Events():
-				if event.Type != types.OpPut {
-					continue
-				}
-				err = authServer.SetAccessRequestState(ctx, types.AccessRequestUpdate{
-					RequestID: event.Resource.(types.AccessRequest).GetName(),
-					State:     types.RequestState_APPROVED,
-				})
-				didAutoRequest.Store(true)
-				errCh <- err
-				return
-			case <-watcher.Done():
-				errCh <- nil
-				return
-			case <-ctx.Done():
-				errCh <- nil
-				return
+		select {
+		case event := <-watcher.Events():
+			if event.Type != types.OpPut {
+				panic(fmt.Sprintf("unexpected event type: %v\n", event))
 			}
+			err = authServer.SetAccessRequestState(ctx, types.AccessRequestUpdate{
+				RequestID: event.Resource.(types.AccessRequest).GetName(),
+				State:     types.RequestState_APPROVED,
+			})
+			if err != nil {
+				panic(fmt.Sprintf("failed to approve request: %v", err))
+			}
+			didAutoRequest.Store(true)
+		case <-watcher.Done():
+			panic(fmt.Sprintf("watcher exited unexpectedly: %v", watcher.Error()))
 		}
 	}()
 
@@ -418,7 +419,6 @@ func TestOIDCLogin(t *testing.T) {
 	})
 
 	require.NoError(t, err)
-	require.NoError(t, <-errCh)
 
 	// verify that auto-request happened
 	require.True(t, didAutoRequest.Load())