ArrayInterator missing __iter__ method

[ellisonbg]

The ArrayIterator is missing the __iter__ method, causing an exception when called (see below). I ran a simple example and verified that iterators need that method. Not sure how the tests are passing though.

[E 2024-12-05 19:14:27.909 ServerApp] Error saving file: Untitled.ipynb
    TypeError("'ArrayIterator' object is not iterable")
    Traceback (most recent call last):
      File "/Users/brgrange/Notebooks/bug398/.pixi/envs/default/lib/python3.13/site-packages/jupyter_server_ydoc/rooms.py", line 285, in _maybe_save_document
        "content": self._document.source,
                   ^^^^^^^^^^^^^^^^^^^^^
      File "/Users/brgrange/Notebooks/bug398/.pixi/envs/default/lib/python3.13/site-packages/jupyter_ydoc/ybasedoc.py", line 90, in source
        return self.get()
               ~~~~~~~~^^
      File "/Users/brgrange/Notebooks/bug398/.pixi/envs/default/lib/python3.13/site-packages/jupyter_ydoc/ynotebook.py", line 204, in get
        cell = self.get_cell(i)
      File "/Users/brgrange/Notebooks/bug398/.pixi/envs/default/lib/python3.13/site-packages/jupyter_ydoc/ynotebook.py", line 106, in get_cell
        cell = self._ycells[index].to_py()
      File "/Users/brgrange/Notebooks/bug398/.pixi/envs/default/lib/python3.13/site-packages/pycrdt/_map.py", line 111, in to_py
        py[key] = val.to_py()
                  ~~~~~~~~~^^
      File "/Users/brgrange/Notebooks/bug398/.pixi/envs/default/lib/python3.13/site-packages/pycrdt/_array.py", line 350, in to_py
        py = [value for value in self]
                                 ^^^^
    TypeError: 'ArrayIterator' object is not iterable

[davidbrochart]

It's the Array that must have an __iter__() method, and it does:

pycrdt/python/pycrdt/_array.py

Line 295 in 3b6c0bb

def __iter__(self) -> ArrayIterator:

[ellisonbg]

I always get confused about this myself. The Array is the iterable, and the ArrayIterator is the iterator. Both of those classes need an __iter__ method.  I found this to be a nice explanation. It looks like you can have an iterator without this method, but that some usage cases like for loops require it.

[davidbrochart]

Thanks, I opened #199.