fixes #6220 - adds check for communicator type and executes the mount script as encoded command via powershell from within 'sh' for communicator != winrm

plugins/guests/windows/cap/mount_shared_folder.rb

@@ -1,4 +1,5 @@
 require "vagrant/util/template_renderer"
+require "base64"
 
 module VagrantPlugins
   module GuestWindows
@@ -33,7 +34,18 @@ module VagrantPlugins
             vm_provider_unc_path: vm_provider_unc_base + name,
           })
 
-          machine.communicate.execute(script, shell: :powershell)
+          if machine.config.vm.communicator == :winrm
+            machine.communicate.execute(script, shell: :powershell)
+          else
+            # Convert script to double byte unicode string then base64 encode
+            # just like PowerShell -EncodedCommand expects.
+            # Suppress the progress stream from leaking to stderr.
+            wrapped_encoded_command = Base64.strict_encode64(
+              "$ProgressPreference='SilentlyContinue'; #{script}; exit $LASTEXITCODE".encode('UTF-16LE', 'UTF-8'))
+            # Execute encoded PowerShell script via OpenSSH shell
+            machine.communicate.execute("powershell.exe -noprofile -executionpolicy bypass " +
+              "-encodedcommand '#{wrapped_encoded_command}'", shell: "sh")
+          end
         end
       end
     end

test/unit/plugins/guests/windows/cap/mount_shared_folder_test.rb

@@ -6,10 +6,15 @@ describe "VagrantPlugins::GuestWindows::Cap::MountSharedFolder" do
 
   let(:machine) { double("machine") }
   let(:communicator) { double(:execute) }
+  let(:config) { double("config") }
+  let(:vm) { double("vm") }
 
   before do
     allow(machine).to receive(:communicate).and_return(communicator)
     allow(communicator).to receive(:execute)
+    allow(machine).to receive(:config).and_return(config)
+    allow(config).to receive(:vm).and_return(vm)
+    allow(vm).to receive(:communicator).and_return(:winrm)
   end
 
   describe "virtualbox" do
@@ -98,4 +103,22 @@ describe "VagrantPlugins::GuestWindows::Cap::MountSharedFolder" do
     end
   end
 
+  describe "virtualbox-ssh" do
+
+    let(:described_class) do
+      VagrantPlugins::GuestWindows::Plugin.components.guest_capabilities[:windows].get(:mount_virtualbox_shared_folder)
+    end
+
+    before do
+      allow(vm).to receive(:communicator).and_return(:ssh)
+    end
+
+    describe ".mount_shared_folder" do
+      it "should call mount_volume script via ssh" do
+        expect(communicator).to receive(:execute).with(/powershell/, shell: "sh")
+        described_class.mount_virtualbox_shared_folder(machine, 'name', 'guestpath', {})
+      end
+    end
+  end
+
 end