why @testing-library/react-native render do not respect !== undefined/ !==null if clause?

Question

I am writing a test using @testing-library/react-native to render my component and test the event onPress when the user press on a flatlist element. I have a list with a couple of elements, however, during its execution, it changes its value to undefined (which I also don't understand). So, when the list is undefined, it tries to render the elements of an undefined list. But the render should only happen when if(myList !== undefined && myList !== null) and it still execute the code inside of this clause. Is it an expected behaviour? How can I stop it of executing it? I also have tested the if clause with if(myList) and having same result.

MyComponent.js

const moods = useSelector(state => state.onboardingReducer.mood);

const renderMoods = (itemData) => {
     console.log('I am on RENDER MOODS')
     if(moods!==undefined && moods !== null){
            console.log('moods ' + JSON.stringify(moods))
            moodsCopy = [...moods];
      } 
      const textStyle = (moodsCopy)? {backgroundColor: 'red'} : {backgroundColor: 'blue'}
      return (<View>
                    <TouchableOpacity
                        onPress={handleOnPress.bind(this, itemData.item)}>
                        <Text style={textStyle} data-testid="text">{itemData.item.title}</Text>
                    </TouchableOpacity>
                </View>);
};

myComponent-test.js

    import { render, fireEvent, waitForElementToBeRemoved } from '@testing-library/react-native';

describe('events',  () => { 
        
        test('On press to remove item', async () => {
            useSelector.mockReturnValueOnce(userInfo).mockReturnValueOnce([ 
                {name: 'Happy', id: '111'},
                {name: 'In Love', id:'111'} 
           ]); 

           const { getByText, getByTestId, debug } = render(<MoodList {...props}/>);

        }
}

On my console I get:

moods [{"name":"Happy","id":"111"},{"name":"In Love","id":"111"}]
I am on RENDER MOODS
moods undefined
I am on RENDER MOODS

And finally I get an error:

TypeError: Invalid attempt to spread non-iterable instance.
    In order to be iterable, non-array objects must have a [Symbol.iterator]() method.