Migration Failure: Check for free space before migration of existing `docker-machine` image

I was excited to see the option to migrate my docker-machine image in the native client. However, I did not have enough disk space to perform the migration. It would have been nice if the app had checked for available disk space first.

Expected behavior

Migration will not begin if there is not enough disk space to perform task.

Actual behavior

Migration begins, runs out of disk space, and fails with an error.

Failed to migrate images and containers: Error converting default volume:
qemu-imgLerror while writting sector 53375488: No space left on device

Information

$ pinata diagnose -u
OS X: version 10.11.4 (build: 15E65)
Docker.app: version v1.11.0-beta7
Running diagnostic tests:
[OK]      docker-cli
[OK]      Moby booted
[OK]      driver.amd64-linux
[OK]      vmnetd
[OK]      osxfs
[OK]      db
[OK]      slirp
[OK]      menubar
[OK]      environment
[OK]      Docker
[OK]      VT-x
Docker logs are being collected into /tmp/20160414-170644.tar.gz
Most specific failure is: No error was detected
Your unique id is: 2767098D-1A06-4FB3-9898-66C48783972D
Please quote this in all correspondence.

Steps to reproduce the behavior

  1. Have a docker-machine image larger than the remaining disk space on your device
  2. Start Docker.app for the first time
  3. Choose to migrate existing images and containers.

I experienced this too on beta13.

Also, recovery from this error (after my root volume on my Mac filled up) could be improved too. I got a Fatal Error from Docker, and then the Docker.app only gave me a choice to acknowledge the error and then exist. So I was unable to use the Docker / Settings / Reset menu item to delete all images and containers. I found the VM image file on my Mac using non-Docker tools, moved it to Trash, and had to reboot before I could empty it from my Trash.

Same issue here, disk full but not sure of migrated vm location.
What was the location of the VM please?