Files missing inside host mounted volume

Expected behavior

All files on the hosts filesystem are accessible when mounted to a container.

Actual behavior

Some files on the hosts filesystem are not accessible when mounted to a container.

Information

$ docker version
Client:
 Version:      1.12.0-rc2
 API version:  1.24
 Go version:   go1.6.2
 Git commit:   906eacd
 Built:        Fri Jun 17 20:35:33 2016
 OS/Arch:      darwin/amd64
 Experimental: true

Server:
 Version:      1.12.0-rc2
 API version:  1.24
 Go version:   go1.6.2
 Git commit:   a7119de
 Built:        Fri Jun 17 22:09:20 2016
 OS/Arch:      linux/amd64
 Experimental: true
  1. Running this command:
$ docker run --rm -it --volume $(pwd)/..:/var/www/htdocs       --hostname memcached myproject-memcached -c bash

should provide access to all project files within the container, however a major difference between the following, on the host:

$ find .

compared to what should be an exact matching output from within the container, with:

$ find /var/www/htdocs/docker

results in the minor difference of:

Comparing: host.txt, container.txt
89,90d88
< ./memcached/_memcached.sh
< ./memcached/Dockerfile
99,100d96
< ./qos-gatekeeper/_gatekeeper.sh
< ./qos-gatekeeper/Dockerfile

Potentially significantly, these files may or may not exist when the Docker for Beta application is started as they exist on a Git feature branch currently, and so if I switch branches these files may disappear. There are however other files unique to this Git branch which are unaffected.

Steps to workaround

Restart Docker for Mac application, and start the container.