Issue with vagrant 2.3.0

[azmng]

Ran into this issue after upgrade to Vagrant version 2.3.0 (Ubuntu 18.04)

$ vagrant up
Vagrant failed to initialize at a very early stage:

There was an error loading a Vagrantfile. The file being loaded
and the error message are shown below. This is usually caused by
an invalid or undefined variable.

Path: /opt/vagrant/embedded/gems/2.3.0/gems/vagrant-2.3.0/plugins/commands/serve/command.rb:24
Line number: 0
Message: uninitialized constant VagrantPlugins::Google::Protobuf

It works well on Vagrant 2.2.19 and previous versions.

Tried plugin versions 2.7.0 and 2.6.0 with the same result.

[RyandenOtter]

I am also experiencing the same issue on an Apple M1 Monterey.

[denders-conception]

I also am having this error on an Apple M1 Monterey.

[MrZeLee]

Same problem in the Apple M1 Monterey.

[ericraio]

Same problem in Apple Intel 2019 Macbook

[ericraio]

I fixed the issue by prepending :: on Empty = Google::Protobuf::Empty

i.e. Empty = ::Google::Protobuf::Empty

in file path /opt/vagrant/embedded/gems/2.3.1/gems/vagrant-2.3.1/plugins/commands/serve/command.rb

[dcode]

@ericraio 's fix worked for me on vagrant version 2.3.2 and plugin version 2.7.0, as well.