Docker command's -v option to mount a file causes it to be mounted as a directory if the local path is not specified

[cspencer404]

Actual Behavior

For the docker command, using the -v option to mount a file causes it to be mounted as a directory when the local path is not specified

Steps to Reproduce

Create a test file

$ cat "Hello World" > test.txt

Mount it in docker using "-v" option for volume mount, get interactive shell in the container

$ docker run -it -v test.txt:/test.txt alpine:latest /bin/sh

Result

List files shows "test.txt" was mounted as a directory, not a file

$ ls -l /
...
drwxr-xr-x    2 root     root          4096 May  9 20:49 test.txt    <--- is a DIR, should be a FILE

Expected Behavior

The file should be mounted as a regular file

-rwxr-xr-x    1 501      dialout        132 May  9 20:49 test.txt

Additional Information

Work-around

When using the local path to the file, the -v option works correctly:

$ docker run -it -v ./test.txt:/test.txt alpine:latest "/bin/sh"

Or, using --mount option instead of -v works correctly, because it requires the path

$ docker run -it --mount type=bind,source=./test.txt,target=/test.txt alpine:latest /bin/sh

$ ls -l then shows:

-rwxr-xr-x    1 501      dialout        132 May  9 20:49 test.txt

Using --mount without the local path gives an error:

docker: Error response from daemon: invalid mount config for type "bind": invalid mount path: 'test.txt' mount path must be absolute.

Rancher Desktop Version

1.13.1

Rancher Desktop K8s Version

n/a

Which container engine are you using?

moby (docker cli)

What operating system are you using?

macOS

Operating System / Build Version

MacOS Ventura 13.6.6 (22G630)

What CPU architecture are you using?

x64

Linux only: what package format did you use to install Rancher Desktop?

None

Windows User Only

No response