Fix E_WARNING access array offset on null when creating new contribution page

[demeritcowboy]

Overview

Before

1. Use php7.4+
2. Create a new contribution page.
3. Can just fill out the minimum needed.
4. Click Continue
5. Fill out the amounts - again can just do the minimum needed.
6. Click Save And Next - Warning: Trying to access array offset on value of type null in CRM_Member_Form_MembershipBlock->setDefaultValues() (line 40 of ...\CRM\Member\Form\MembershipBlock.php).

After

Technical Details

Line 38 can return null if there is no membership block yet

Comments

[civibot]

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[eileenmcnaughton]

I'm thinking the issue is defaults isn't an array? If this works for you I'm fine with it but I suspect we should ensure defaults is an array

[demeritcowboy]

It isn't an array - it's null. But my thinking was even if it was an empty array it would still give a notice here, so this works either way and then I don't have to look around for who else calls that function expecting null.

[eileenmcnaughton]

Ok - it just feels like we might get more grumpiness in php 8 or something - but we can deal with that when it comes!

[demeritcowboy]

Fair point - maybe php 9 since php 8 seems ok with it so that buys at least a month.

Oh by the way php 9 is going back to $x = array('a' => 'b'); syntax.
... Kidding!

[eileenmcnaughton]

lol!

[demeritcowboy]

jenkins retest this please