Set hostname in /etc/hosts as first step to changing hostname

plugins/guests/debian/cap/change_host_name.rb

@@ -1,5 +1,6 @@
 require "log4r"
 require 'vagrant/util/guest_hosts'
+require 'vagrant/util/guest_inspection'
 require_relative "../../linux/cap/network_interfaces"
 
 module VagrantPlugins
@@ -15,6 +16,13 @@ module VagrantPlugins
           comm = machine.communicate
 
           if !comm.test("hostname -f | grep '^#{name}$'", sudo: false)
+            network_with_hostname = machine.config.vm.networks.map {|_, c| c if c[:hostname] }.compact[0]
+            if network_with_hostname
+              replace_host(comm, name, network_with_hostname[:ip])
+            else
+              add_hostname_to_loopback_interface(comm, name)
+            end
+
             basename = name.split(".", 2)[0]
             comm.sudo <<-EOH.gsub(/^ {14}/, '')
               # Set the hostname
@@ -58,13 +66,6 @@ module VagrantPlugins
               restart_each_interface(machine, @logger)
             end
           end
-
-          network_with_hostname = machine.config.vm.networks.map {|_, c| c if c[:hostname] }.compact[0]
-          if network_with_hostname
-            replace_host(comm, name, network_with_hostname[:ip])
-          else
-            add_hostname_to_loopback_interface(comm, name)
-          end
         end
 
         protected

test/unit/plugins/guests/debian/cap/change_host_name_test.rb

@@ -36,6 +36,8 @@ describe "VagrantPlugins::GuestDebian::Cap::ChangeHostName" do
       allow(cap).to receive(:systemd_networkd?).and_return(networkd)
       allow(cap).to receive(:systemd_controlled?).with(anything, /NetworkManager/).and_return(network_manager)
       allow(machine).to receive_message_chain(:config, :vm, :networks).and_return(networks)
+      allow(cap).to receive(:add_hostname_to_loopback_interface)
+      allow(cap).to receive(:replace_host)
     end
 
     context "minimal network config" do
@@ -153,8 +155,9 @@ describe "VagrantPlugins::GuestDebian::Cap::ChangeHostName" do
 
     it "does not set the hostname if unset" do
       comm.stub_command("hostname -f | grep '^#{name}$'", exit_code: 0)
+      expect(cap).to_not receive(:add_hostname_to_loopback_interface)
+      expect(cap).to_not receive(:replace_host)
       cap.change_host_name(machine, name)
-      expect(comm.received_commands.size).to eq(2)
     end
   end