guests/redhat: Install RedHat in one command

plugins/guests/redhat/cap/rsync.rb

@@ -3,13 +3,13 @@ module VagrantPlugins
     module Cap
       class RSync
         def self.rsync_install(machine)
-          machine.communicate.tap do |comm|
-            if VagrantPlugins::GuestRedHat::Plugin.dnf?(machine)
-              comm.sudo("dnf -y install rsync")
+          machine.communicate.sudo <<-EOH.gsub(/^ {12}/, '')
+            if command -v dnf; then
+              dnf -y install rsync
             else
-              comm.sudo("yum -y install rsync")
-            end
-          end
+              yum -y install rsync
+            fi
+          EOH
         end
       end
     end

test/unit/plugins/guests/redhat/cap/rsync_test.rb

@@ -0,0 +1,29 @@
+require_relative "../../../../base"
+
+describe "VagrantPlugins::GuestRedHat::Cap:RSync" do
+  let(:caps) do
+    VagrantPlugins::GuestRedHat::Plugin
+      .components
+      .guest_capabilities[:redhat]
+  end
+
+  let(:machine) { double("machine") }
+  let(:comm) { VagrantTests::DummyCommunicator::Communicator.new(machine) }
+
+  before do
+    allow(machine).to receive(:communicate).and_return(comm)
+  end
+
+  after do
+    comm.verify_expectations!
+  end
+
+  describe ".rsync_install" do
+    let(:cap) { caps.get(:rsync_install) }
+
+    it "installs rsync" do
+      cap.rsync_install(machine)
+      expect(comm.received_commands[0]).to match(/install rsync/)
+    end
+  end
+end