Before this change, this would cause a panic:
docker run -it --rm -v 1:/1 alpine
panic: runtime error: index out of range
goroutine 1 [running]:
github.com/docker/cli/cli/compose/loader.isFilePath(0xc42027e058, 0x1, 0x557dcb978c20)
...
After this change, a correct error is returned:
docker run -it --rm -v 1:/1 alpine
docker: Error response from daemon: create 1: volume name is too short, names should be at least two alphanumeric characters.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>