[Autocomplete] Fix auto highlight when options change but not the length

packages/mui-material/src/Autocomplete/Autocomplete.test.js

@@ -369,6 +369,57 @@ describe('<Autocomplete />', () => {
       fireEvent.change(textbox, { target: { value: 'a' } });
       checkHighlightIs(getByRole('listbox'), 'Bar');
     });
+
+    // https://github.com/mui/material-ui/issues/45279
+    it('should auto highlight first option after options order changes with autoHighlight', () => {
+      const { setProps, getByRole } = render(
+        <Autocomplete
+          autoHighlight
+          open
+          options={['pediatric ent', 'pediatric flu', 'pediatrician', 'pediatric cough']}
+          renderInput={(params) => <TextField {...params} autoFocus />}
+        />,
+      );
+
+      checkHighlightIs(getByRole('listbox'), 'pediatric ent');
+      setProps({
+        options: ['pediatrician', 'pediatric ent', 'pediatric flu', 'pediatric cough'],
+      });
+      checkHighlightIs(getByRole('listbox'), 'pediatrician');
+    });
+
+    it('should auto highlight first option when no match with input value with autoHighlight', () => {
+      const { getByRole } = render(
+        <Autocomplete
+          open
+          autoHighlight
+          options={['1', '2', '3', '4']}
+          value="5"
+          renderInput={(params) => <TextField {...params} autoFocus />}
+        />,
+      );
+
+      checkHighlightIs(getByRole('listbox'), '1');
+    });
+
+    it('should auto highlight first option of rest after selecting an option with autoHighlight and filterSelectedOptions', () => {
+      const { getByRole } = render(
+        <Autocomplete
+          open
+          autoHighlight
+          options={['1', '2', '3', '4']}
+          renderInput={(params) => <TextField {...params} autoFocus />}
+          filterSelectedOptions
+          disableCloseOnSelect
+        />,
+      );
+
+      const textbox = getByRole('combobox');
+
+      checkHighlightIs(getByRole('listbox'), '1');
+      fireEvent.keyDown(textbox, { key: 'Enter' });
+      checkHighlightIs(getByRole('listbox'), '2');
+    });
   });
 
   describe('highlight synchronisation', () => {

packages/mui-material/src/useAutocomplete/useAutocomplete.js

@@ -7,6 +7,15 @@ import useControlled from '@mui/utils/useControlled';
 import useId from '@mui/utils/useId';
 import usePreviousProps from '@mui/utils/usePreviousProps';
 
+function areArraysSame({ array1, array2, parser = (value) => value }) {
+  return (
+    array1 &&
+    array2 &&
+    array1.length === array2.length &&
+    array1.every((prevOption, index) => parser(prevOption) === parser(array2[index]))
+  );
+}
+
 // https://stackoverflow.com/questions/990904/remove-accents-diacritics-in-a-string-in-javascript
 function stripDiacritics(string) {
   return string.normalize('NFD').replace(/[\u0300-\u036f]/g, '');
@@ -456,6 +465,12 @@ function useAutocomplete(props) {
     }
   });
 
+  const filteredOptionsChanged = !areArraysSame({
+    array1: previousProps.filteredOptions,
+    array2: filteredOptions,
+    parser: getOptionLabel,
+  });
+
   const getPreviousHighlightedOptionIndex = () => {
     const isSameValue = (value1, value2) => {
       const label1 = value1 ? getOptionLabel(value1) : '';
@@ -465,8 +480,11 @@ function useAutocomplete(props) {
 
     if (
       highlightedIndexRef.current !== -1 &&
-      previousProps.filteredOptions &&
-      previousProps.filteredOptions.length !== filteredOptions.length &&
+      !areArraysSame({
+        array1: previousProps.filteredOptions,
+        array2: filteredOptions,
+        parser: getOptionLabel,
+      }) &&
       previousProps.inputValue === inputValue &&
       (multiple
         ? value.length === previousProps.value.length &&
@@ -597,8 +615,10 @@ function useAutocomplete(props) {
   }
 
   React.useEffect(() => {
-    syncHighlightedIndex();
-  }, [syncHighlightedIndex]);
+    if (filteredOptionsChanged) {
+      syncHighlightedIndex();
+    }
+  }, [syncHighlightedIndex, filteredOptionsChanged]);
 
   const handleOpen = (event) => {
     if (open) {