Override Stream.CopyTo on FileStream

[stephentoub]

Stream.CopyTo was made virtual in a previous release of .NET Core. We override CopyToAsync on FileStream, but we don't currently override CopyTo.

EDIT: See dotnet/coreclr#17978 (comment) for some thoughts.

[JeremyKuhne]

@stephentoub is this something you want to take care of? Or is this a good candidate for up-for-grabs?

[stephentoub]

Marked it up-for-grabs.

[tdinucci]

I'd be happy to take this one

[JeremyKuhne]

@tdinucci Great! @karelz, can you get him set up so we can assign the issues?

[karelz]

@tdinucci I just sent you collaborator invite. Once you accept, we can assign it to you - it's GH limitation (just ping me and I will do that, assigning to myself temporarily).
Pro-tip: Becoming collaborator will automatically subscribe you to all notifications on the repo (500+ daily). We recommend to flip it to "Not Watching" which will send you notifications only on issues where you are mentioned, assigned, or explicitly subscribed.

[tdinucci]

👍

@karelz, thanks for the tip. I've accepted invite now

[tdinucci]

@karelz, forgot to confirm. My understanding is that I should be working on coreclr for this. After I submit PR on coreclr I should wait a couple of days and then submit PR for unit tests on corefx. Is this correct?

[karelz]

@tdinucci I let @JeremyKuhne confirm what has to happen where and when.

[JeremyKuhne]

@tdinucci Create both PRs to show that you have tested. If you haven't seen them already, instructions for consuming your own CoreCLR are here: https://github.com/dotnet/corefx/blob/master/Documentation/project-docs/developer-guide.md#testing-with-private-coreclr-bits

You can mark the test PR as no merge pending integration of the dependent change in CoreCLR.

[stephentoub]

Determined not to be worthwhile.