gh-998: Change all references to len to .shape[0]

[paddyroddy]

Description

The Array API spec doesn't have a definition of len(). This PR changes .size references to .shape[0]. It also changes some current len() to .shape[0].

Closes: #998

Checks

• Is your code passing linting?
• Is your code passing tests?
• Have you added additional tests (if required)?
• Have you modified/extended the documentation (if required)?
• Have you added a one-liner changelog entry above (if required)?

[connoraird]

I assume that the instances of size which are now shape[0] used to be len or are being applied to a cl?

[paddyroddy]

I assume that the instances of size which are now shape[0] used to be len or are being applied to a cl?

See 6a12b05

[connoraird]

See 6a12b05

So are we not sure if they used to be len before they were converted to size?

[paddyroddy]

So are we not sure if they used to be len before they were converted to size?

I wasn't clear what you were asking. I guess not.

[connoraird]

I wasn't clear what you were asking. I guess not.

If we trust our tests then this is okay

[paddyroddy]

If we trust our tests then this is okay

I probably don't... Will check tomorrow.

[paddyroddy]

I probably don't... Will check tomorrow.

I've been more cautious and reverted all of them unless cl or in tests.