Function waitForNewSubConns

balancer/weightedtarget/weightedtarget_test.go:1284–1312

waitForNewSubConns waits for `num` number of subConns to be created. This is expected to be used from tests using the "test_config_balancer" LB policy, which adds an address attribute with value set to the balancer config. Returned value is a map from subBalancer (identified by its config) to subCo

(ctx context.Context, t *testing.T, cc *testutils.BalancerClientConn, num int)

// Returned value is a map from subBalancer (identified by its config) to
// subConns created by it.
func waitForNewSubConns(ctx context.Context, t *testing.T, cc *testutils.BalancerClientConn, num int) map[string][]subConnWithAddr {
	t.Helper()

	scs := make(map[string][]subConnWithAddr)
	for i := 0; i < num; i++ {
		var addrs []resolver.Address
		select {
		case <-ctx.Done():
			t.Fatalf("Timed out waiting for addresses for new SubConn.")
		case addrs = <-cc.NewSubConnAddrsCh:
		}
		if len(addrs) != 1 {
			t.Fatalf("received subConns with %d addresses, want 1", len(addrs))
		}
		cfg, ok := getConfigKey(addrs[0].Attributes)
		if !ok {
			t.Fatalf("received subConn address %v contains no attribute for balancer config", addrs[0])
		}
		var sc balancer.SubConn
		select {
		case <-ctx.Done():
			t.Fatalf("Timed out waiting for new SubConn.")
		case sc = <-cc.NewSubConnCh:
		}
		scWithAddr := subConnWithAddr{sc: sc, addr: addrs[0]}
		scs[cfg] = append(scs[cfg], scWithAddr)
	}
	return scs
}

func verifySubConnAddrs(t *testing.T, scs map[string][]subConnWithAddr, wantSubConnAddrs map[string][]resolver.Address) {
	t.Helper()