When the ArrowLeft key is pressed while there are selected options and renderTags is set to return null (so that no tags are rendered), the component breaks.

• The issue is present in the latest release.
• I have searched the issues of this repository and believe that this is not a duplicate.

Current Behavior 😯

When the ArrowLeft key is pressed while there are selected options and renderTags is set to return null (so that no tags are rendered), the component breaks and returns the error describe below:

It appears that the useAutocomplete hook tries to put focus on the tag elements without checking whether there are tags rendered or not as per the source code:

  const focusTag = useEventCallback((tagToFocus) => {
    if (tagToFocus === -1) {
      inputRef.current.focus();
    } else {
      anchorEl.querySelector(`[data-tag-index="${tagToFocus}"]`).focus(); // <-- The line in question.
    }
  });

Expected Behavior 🤔

When the ArrowLeft key is pressed while there are selected options and renderTags is set to return null, it shouldn't try to put focus on tags.

Steps to Reproduce 🕹

Codesandbox link: https://codesandbox.io/s/nt24o
Taken from: https://material-ui.com/components/autocomplete/#githubs-picker

Steps:

1. Open the Autocomplete component by clicking on Labels.
2. Make sure there are options selected.
3. Make sure the Autocomplete input field is focused.
4. Press the ArrowLeft key. Error should appear.

Context 🔦

We are trying to build a component similar to the Github Labels picker sample provided by the docs: https://material-ui.com/components/autocomplete/#githubs-picker because we need a filterable/searchable dropdown component, but we don't need to show tags/chips because we want the input field of the Autocomplete to just act like an input for filtering.

Your Environment 🌎

Browser used: Chrome

  System:
    OS: macOS 10.15.7
  Binaries:
    Node: 14.17.0 - ~/.nvm/versions/node/v14.17.0/bin/node
    Yarn: 1.22.10 - /usr/local/bin/yarn
    npm: 6.14.13 - ~/.nvm/versions/node/v14.17.0/bin/npm
  Browsers:
    Chrome: 92.0.4515.131
    Edge: 92.0.902.78
    Firefox: 91.0
    Safari: 14.1.2