get_block_wrapper_attributes(): Preserve zero value

[t-hamano]

Trac ticket: https://core.trac.wordpress.org/ticket/64452

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[ramonjd]

This is the meat of the fix, right? It looks right to me, and cover edge cases:

• 0 (integer): (string) 0 = "0" ≠ "" → treated as valid
• "0" (string): (string) "0" = "0" ≠ "" → treated as valid
• "" (empty string): (string) "" = "" = "" → treated as empty (correct)
• false: (string) false = "" = "" → treated as empty (acceptable for HTML attributes)
• null: (string) null = "" = "" → treated as empty (acceptable)

[t-hamano]

That's right. The main reason for using a string cast is to allow zero as a number or a string, but to exclude false or null.

[ramonjd]

Thanks for the tests! LGTM

I tested manually with the calendar block and a block anchor of 0.

Without this patch the id wasn't rendered, with this patch:

<div class="wp-block-calendar" id="0">

[ramonjd]

What are the changes here? the array_key_exists checks? It is worth adding a @since x.x.x with a note?

[t-hamano]

Thanks both for your reviews!

I thought it was odd to have the get_block_wrapper_attributes function in a class file, so I moved it to block.php, but it became harder to see what had changed 😅 For now, I'll revert the function to its original position. Regarding moving the function location, let's address it in a follow-up PR.

[t-hamano]

Thanks to both of you for the reviews! Before making any changes to this PR, I'd like to double-check what values ​​should be allowed for the attribute.

My understanding is as follows, but what do you think?

• ✅ Allow as valid value:
  • "0" (String)
  • 0 (Integer) → Should be converted to a string "0"
• ❌ Don't allow as invalid value
  • true (boolean)
  • false (boolean)
  • null
  • array() (array)

[t-hamano]

Oh, I re-forked the wordpress-develop repo and it seems all my submitted open PRs were closed 😂 I submitted a new PR that is equivalent to this one. #10921