message: checking if connecting to a source with no inputs throws an error
diff: import { PassesAudio } from "@tonejs/plot";
  import { expect } from "chai";
  import { Offline } from "test/helper/Offline";
  +import { Oscillator } from "../source/oscillator/Oscillator";
  import { connect, disconnect } from "./Connect";
  import { Gain } from "./context/Gain";
  @@ -57,6 +58,16 @@ describe("Connect", () => {
  expect(threwError).to.equal(true);
  });
  + it ("throws an error if the destination has no input", () => {
  + const source = new Oscillator();
  + const gain = new Gain();
  + expect(() => {
  + gain.connect(source);
  + }).to.throw(Error);
  + gain.dispose();
  + source.dispose();
  + });
  +
  it("throws an error if things aren't connected to a specific channel", async () => {
  let threwError = false;
  await PassesAudio((context, input, output) => {
  