[Python] Expose MakeArray to construct arrays from buffers

[asfimport]

To create new arrays from existing buffers in Python, we would need to call into the C++ MakeArray method. This would then construct the Array and we would only wrap it in Python to have construction support for all Array types.

This would also mean that we need to have a Python representation of ArrayData

Reporter: Uwe Korn / @xhochy
Assignee: Antoine Pitrou / @pitrou

PRs and other links:

• GitHub Pull Request #1772

_{Note: This issue was originally created as ARROW-2281. Please see the migration documentation for further details.}

[asfimport]

Antoine Pitrou / @pitrou:
I'm not sure we need to expose ArrayData in Python. We could simply make it implicit in our factory method, e.g.:

cdef class Array:
    @classmethod
    def from_buffers(cls, type, length, buffers, null_count=-1, offset=0):
        ...

[asfimport]

Wes McKinney / @wesm:
If we can avoid exposing the extra data structure, that might be best.

[asfimport]

Wes McKinney / @wesm:
Issue resolved by pull request 1772
#1772