Best way to check if variable is set and can be 'foreach'ed

Question

I've taken over a larger code base, that has several warnings and errors.

I keep running into statements like this:

foreach( $object->keys => $key ){
  ...
}

Where I can see in the error log, that $object is null.

What is the simplest way, tot check that above-written statement won't break?

---

To be 100% sure, I would do something like this:

if( isset( $object ) && is_array( $object->keys ) ){
  foreach( $object->keys => $key ){
    ...
  }
}

But the readability decreases significantly.

I could also make a helper function, that did it, like so:

if( myHelper::canBeForeached( $object, 'keys' ) ){ // naming would obviously be changed
  foreach( $object->keys => $key ){
    ...
  }
}

But that too seems bad.

What is the simplest/prettiest way to achieve this, to also maintain readability of the code?