podman cp extracts tarballs, unlike docker cp command

[afbjorklund]

Is this a BUG REPORT or FEATURE REQUEST? (leave only one on its own line)

/kind bug

Description

The new cp command has some kind of auto-extract feature ?

Steps to reproduce the issue:

1. sudo podman cp tinycore-tar-exporter:/tmp/rootfs64.tar.gz ./

Describe the results you received:

The results of the tarball was extracted.

Describe the results you expected:

The file to be copied, without extraction.

Output of podman version:

Version:            1.2.0-dev
RemoteAPI Version:  1
Go Version:         go1.12
Git Commit:         f3a3d8e28e4b8ec06dd11ec156c10e243165f19d
Built:              Sun Mar  3 20:50:19 2019
OS/Arch:            linux/amd64

[rhatdan]

@QiWang19 Very the behaviour versus Docker, and make sure we match.