Fixup pickle, add copy

[jcrist]

• Fixes pickle of COO to exclude the _cache attribute
• Adds a COO.copy method to mirror numpy.

[hameerabbasi]

This looks great! An addition to the changelog is always nice. :-)

And separated tests.

[jcrist]

I've been avoiding adding things to the changelog until approved because every merged PR results in merge conflicts for existing PRs. Other repos solve this by:

• Adding placeholder list elements to be edited later (git merge works better when editing a list element than adding a new line)
• Holding off on adding changelog entries until release
• Adding a separate tiny file in a directory for each new change, and merging these together on release
• Inserting items in the changelog rather than prepending, minimizing chances for conflicts over time.

Unfortunately none of these work with the sphinx releases extension you're using to generate a running changelog. I'm not sure if anything should be done to change this.

[hameerabbasi]

Merging, thanks.

[dhirschfeld]

It can be very painful for contributors to have to deal with CHANGELOG merge conflicts.

I've also seen it done where an issue CHANGELOG - 0.4.2 is created and the changelog entries are accumulated there and only moved to the actual changelog file when the when the release is made.

[mrocklin]

FWIW in Dask we stopped asking people to provide changelog entries on every PR. I tend to add these all afterwards when we go to release. This seems to be smoother overall.

…

On Tue, Sep 18, 2018 at 11:36 PM Dave Hirschfeld ***@***.***> wrote: It can be very painful for contributors to have to deal with CHANGELOG merge conflicts. I've also seen it done where an issue CHANGELOG - 0.4.2 is created and the changelog entries are accumulated there and only moved to the actual changelog file when the when the release is made. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#184 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AASszF5RhqFGaafShIPKLQpvy8d8KV65ks5ucbvIgaJpZM4Ws0m4> .

[hameerabbasi]

That seems like a good way to go, but you lose out on "what's coming next" for the uninitiated.