From dc3b69664f8c27acbac56e249e81ae8e761363ac Mon Sep 17 00:00:00 2001
From: Ali Sasani <alisasanibab@gmail.com>
Date: Thu, 30 Dec 2021 13:35:08 +0330
Subject: [PATCH] [Autocomplete] Fix calling onChange for duplicate values
 (#30374)

---
 .../AutocompleteUnstyled/useAutocomplete.js   |  6 ++++-
 .../src/Autocomplete/Autocomplete.test.js     | 24 +++++++++++++++++++
 2 files changed, 29 insertions(+), 1 deletion(-)

diff --git a/packages/mui-base/src/AutocompleteUnstyled/useAutocomplete.js b/packages/mui-base/src/AutocompleteUnstyled/useAutocomplete.js
index b028d19ec9726d..ef943fa4a68dd1 100644
--- a/packages/mui-base/src/AutocompleteUnstyled/useAutocomplete.js
+++ b/packages/mui-base/src/AutocompleteUnstyled/useAutocomplete.js
@@ -570,7 +570,11 @@ export default function useAutocomplete(props) {
   };
 
   const handleValue = (event, newValue, reason, details) => {
-    if (value === newValue) {
+    if (Array.isArray(value)) {
+      if (value.length === newValue.length && value.every((val, i) => val === newValue[i])) {
+        return;
+      }
+    } else if (value === newValue) {
       return;
     }
 
diff --git a/packages/mui-material/src/Autocomplete/Autocomplete.test.js b/packages/mui-material/src/Autocomplete/Autocomplete.test.js
index 26b9f892d58016..27210e8919720b 100644
--- a/packages/mui-material/src/Autocomplete/Autocomplete.test.js
+++ b/packages/mui-material/src/Autocomplete/Autocomplete.test.js
@@ -502,6 +502,30 @@ describe('<Autocomplete />', () => {
       expect(textbox).toHaveFocus();
     });
 
+    it('should not call onChange function for duplicate values', () => {
+      const handleChange = spy();
+      const options = ['one', 'two'];
+      render(
+        <Autocomplete
+          freeSolo
+          defaultValue={options}
+          options={options}
+          onChange={handleChange}
+          renderInput={(params) => <TextField {...params} autoFocus />}
+          multiple
+        />,
+      );
+      const textbox = screen.getByRole('textbox');
+
+      fireEvent.change(textbox, { target: { value: 'two' } });
+      fireEvent.keyDown(textbox, { key: 'Enter' });
+      expect(handleChange.callCount).to.equal(0);
+
+      fireEvent.change(textbox, { target: { value: 'three' } });
+      fireEvent.keyDown(textbox, { key: 'Enter' });
+      expect(handleChange.callCount).to.equal(1);
+    });
+
     it('has no textbox value', () => {
       render(
         <Autocomplete