Material-ui: [Autocomplete] Return key clears currently selected option

[chapmanio]

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

Current Behavior 😯

After selecting an option, if you press the "enter" (return) keyboard key, the value is cleared.

Expected Behavior 🤔

If wrapped in a form element, the return key should trigger a submit of that form.

Possibly, if the disableClearable prop is set to false then the return key _could_ be seen as clicking the "X" button to clear the field. If it is set to true then it shouldn't clear anything!

Steps to Reproduce 🕹

It's present on all of the demos on https://material-ui.com/components/autocomplete/ if you select an option for any of the demos and then press the "enter" key, the value is removed/cleared.

Context 🔦

I have a form with a single autocomplete field, the only other action is a button to submit the form.

After interacting with the autocomplete field and selecting a value, I wanted to trigger the form submit by using the "enter" key, rather than tabbing to the submit button and then pressing "enter".

Using the "enter" key to submit a form is expected behaviour (for me at least!), and having it clear the current field is the opposite of what I was expecting.

[oliviertassinari]

@chapmanio Thank you for the bug report! Yeah, it's not great!

diff --git a/packages/material-ui-lab/src/useAutocomplete/useAutocomplete.js b/packages/material-ui-lab/src/useAutocomplete/useAutocomplete.js
index 72d7c84c3..2a447c1a1 100644
--- a/packages/material-ui-lab/src/useAutocomplete/useAutocomplete.js
+++ b/packages/material-ui-lab/src/useAutocomplete/useAutocomplete.js
@@ -527,7 +527,7 @@ export default function useAutocomplete(props) {
         handleFocusTag(event, 'next');
         break;
       case 'Enter':
-        if (highlightedIndexRef.current !== -1) {
+        if (highlightedIndexRef.current !== -1 && popupOpen) {
           // We don't want to validate the form.
           event.preventDefault();
           selectNewValue(event, filteredOptions[highlightedIndexRef.current]);

What do you think of this fix? Do you want to submit a pull request? :)