Function start

packages/dva/src/index.js:44–82

(container)

  }

  function start(container) {
    // 允许 container 是字符串，然后用 querySelector 找元素
    if (isString(container)) {
      container = document.querySelector(container);
      invariant(
        container,
        `[app.start] container ${container} not found`,
      );
    }

    // 并且是 HTMLElement
    invariant(
      !container || isHTMLElement(container),
      `[app.start] container should be HTMLElement`,
    );

    // 路由必须提前注册
    invariant(
      app._router,
      `[app.start] router must be registered before app.start()`,
    );

    if (!app._store) {
      oldAppStart.call(app);
    }
    const store = app._store;

    // export _getProvider for HMR
    // ref: https://github.com/dvajs/dva/issues/469
    app._getProvider = getProvider.bind(null, store, app);

    // If has container, render; else, return react component
    if (container) {
      render(container, store, app, app._router);
      app._plugin.apply('onHmr')(render.bind(null, container, store, app));
    } else {
      return getProvider(store, this, this._router);
    }
  }
}

function isHTMLElement(node) {