ArrayInput remove an item on a flat string array

[divanitskiy]

What you were expecting:
ArrayInput component should remove the exact item a user clicks.

Initial data:
string_array: ["val1"]

What happened instead:
A wrong item was removed.

Steps to reproduce:
Scenario 1.

1. Edit a post. Note that it contains: string_array: ["val1"]
2. Add a second item to the String array property and leave it empty.
3. Add a third item val3.
4. Try removing the first item - the second item is removed instead.

Scenario 2.

1. Edit a post. Note that it contains: string_array: ["val1"]
2. Remove the first item of the String array property.
3. Add a new item - it should be empty but we get val1 instead.

Related code:

https://codesandbox.io/s/loving-shockley-fbvq2?file=/src/data.tsx

<ArrayInput source="string_array">
            <SimpleFormIterator>
              <TextInput source="" fullWidth />
            </SimpleFormIterator>
</ArrayInput>

Other information:

Environment

• React-admin version: 3.19.6
• Last version that did not exhibit the issue (if applicable):
• React version: 17.0.0
• Browser: Chrome
• Stack trace (in case of a JS error):

[WiXSL]

Thanks for the report.

[WiXSL]

Fixed by #7123