If SchemaArticleImage url is empty, we shouldn't render the object at all

Improved wording. Added STR.

That seems entirely reasonable.

At a surface level we should make sure that the Image object does not output if the URL value is empty.

We should (separately) look at whether it would be possible to indicate required values that would cause the structure to not be output at all if they are not present.

@DamienMcKenna I was wondering if it would make sense to introduce e.g. a SchemaImageObjectBase class, and try to imitate more accurately the types specificity of Schema.org Types instead of all tags inheriting from SchemaNameBase. But yes, definitely out of scope here.

Well, maybe not that out of scope. I'm pretty sure I will encounter the same issue if I test HowTo schemas. This should fix all.

+++ b/src/Plugin/metatag/Tag/SchemaImageObjectBase.php
@@ -0,0 +1,32 @@
+  public function output(): array {
...
+      return '';

This is problematic. We use empty string, but the function contract returned value is array.
This is already a problem in HEAD with SchemaNameBase::output()

I'm using 2.4 so this might work for me, but definitely we need a different solution here.

That's pretty good, thank you.

What happens if it returns an empty array instead of an empty string?

Ah, it actually works, wasn't 100% confident.

Committed. Thank you.

+++ b/src/Plugin/metatag/Tag/SchemaImageObjectBase.php
@@ -0,0 +1,32 @@
+/**
...
+ */
+class SchemaImageObjectBase extends SchemaNameBase {

Just found that I copypasted this and the comment should say

All Schema.org **images** should extend this class.

Committed. Thanks for the follow-up.

Automatically closed - issue fixed for 2 weeks with no activity.