}

	if e := "|http|" + ts.Listener.Addr().String(); keys[0] != e {
		t.Errorf("Expected idle cache key %q; got %q", e, keys[0])
	}

	tr.CloseIdleConnections()
	if e, g := 0, len(tr.IdleConnKeysForTesting()); e != g {
		t.Errorf("After CloseIdleConnections expected %d idle conn cache keys; got %d", e, g)
	}
}

// Tests that the HTTP transport re-uses connections when a client

	}()
	readRes := make(chan error, 1)
	go func() {
		_, err := c.Read([]byte{0})
		readRes <- err
	}()

	// TODO(#59037): This timeout is hard-coded in closeIdleConnections.
	// It is undocumented, and some users may find it surprising.
	// Either document it, or switch to a less surprising behavior.
	const expectTimeout = 5 * time.Second

	t0 := time.Now()
	select {