filer.copy: destination XYZ uses collection "asagi-images": unexpected collection "asagi-images"

[Suika]

Describe the bug

$ weed filer.copy -collection=asagi-images e/image http://localhost:8888/buckets/asagi-images/e/image/
destination /buckets/asagi-images/e/image/ uses collection "asagi-images": unexpected collection "asagi-images"

Probably 147d4d2 is the cause of it or at least started to happen after that.

System Setup

• Docker Setup, see Max number of volumes on volume server are not recalculated on diskspace change #1594
• Debian 9
• version 8000GB 2.10 15956d8 linux amd64
• Default docker filer config

Expected behavior
If copying data to a bucket and the right collection is definied in the arguments, do not error out.
If a different collection is defined in the arguments than the one of the bucket, error out.

I know that the collection does not need be defined in the arguments, but still.

[chrislusf]

Thanks for the detailed issue report!