Make atomic-host guest respect 'hostname' network config option

plugins/guests/atomic/cap/change_host_name.rb

@@ -1,7 +1,11 @@
+require 'vagrant/util/guest_hosts'
+
 module VagrantPlugins
   module GuestAtomic
     module Cap
       class ChangeHostName
+        extend Vagrant::Util::GuestHosts::Linux
+
         def self.change_host_name(machine, name)
           comm = machine.communicate
 
@@ -10,13 +14,14 @@ module VagrantPlugins
             comm.sudo <<-EOH.gsub(/^ {14}/, "")
               # Set hostname
               hostnamectl set-hostname '#{basename}'
-
-              # Prepend ourselves to /etc/hosts
-              test $? -eq 0 && (grep -w '#{name}' /etc/hosts || {
-                sed -i'' '1i 127.0.0.1\\t#{name}\\t#{basename}' /etc/hosts
-              })
             EOH
           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
       end
     end

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

@@ -1,14 +1,17 @@
 require_relative "../../../../base"
 
 describe "VagrantPlugins::GuestAtomic::Cap::ChangeHostName" do
-  let(:caps) do
+  let(:described_class) do
     VagrantPlugins::GuestAtomic::Plugin
       .components
       .guest_capabilities[:atomic]
+      .get(:change_host_name)
   end
 
   let(:machine) { double("machine") }
   let(:comm) { VagrantTests::DummyCommunicator::Communicator.new(machine) }
+  let(:name) { "banana-rama.example.com" }
+  let(:basename) { "banana-rama" }
 
   before do
     allow(machine).to receive(:communicate).and_return(comm)
@@ -19,21 +22,54 @@ describe "VagrantPlugins::GuestAtomic::Cap::ChangeHostName" do
   end
 
   describe ".change_host_name" do
-    let(:cap) { caps.get(:change_host_name) }
+    context "minimal network config" do 
+      let(:networks) { [
+        [:forwarded_port, {:guest=>22, :host=>2222, :host_ip=>"127.0.0.1", :id=>"ssh", :auto_correct=>true, :protocol=>"tcp"}]
+      ] }
 
-    let(:name) { "banana-rama.example.com" }
+      before do 
+        allow(machine).to receive_message_chain(:config, :vm, :networks).and_return(networks)
+      end
 
-    it "sets the hostname" do
-      comm.stub_command("hostname -f | grep '^#{name}$'", exit_code: 1)
+      it "sets the hostname" do
+        comm.stub_command("hostname -f | grep '^#{name}$'", exit_code: 1)
 
-      cap.change_host_name(machine, name)
-      expect(comm.received_commands[1]).to match(/hostnamectl set-hostname 'banana-rama'/)
+        described_class.change_host_name(machine, name)
+        expect(comm.received_commands[1]).to match(/hostnamectl set-hostname '#{basename}'/)
+      end
+
+      it "does not change the hostname if already set" do
+        comm.stub_command("hostname -f | grep '^#{name}$'", exit_code: 0)
+
+        described_class.change_host_name(machine, name)
+        expect(comm).to_not receive(:sudo).with(/hostnamectl set-hostname/)
+      end
     end
 
-    it "does not change the hostname if already set" do
-      comm.stub_command("hostname -f | grep '^#{name}$'", exit_code: 0)
-      cap.change_host_name(machine, name)
-      expect(comm.received_commands.size).to eq(1)
+    context "multiple networks configured with hostname" do 
+      it "adds a new entry only for the hostname" do 
+        networks = [
+          [:forwarded_port, {:guest=>22, :host=>2222, :host_ip=>"127.0.0.1", :id=>"ssh", :auto_correct=>true, :protocol=>"tcp"}],
+          [:public_network, {:ip=>"192.168.0.1", :hostname=>true, :protocol=>"tcp", :id=>"93a4ad88-0774-4127-a161-ceb715ff372f"}],
+          [:public_network, {:ip=>"192.168.0.2", :protocol=>"tcp", :id=>"5aebe848-7d85-4425-8911-c2003d924120"}]
+        ]
+        allow(machine).to receive_message_chain(:config, :vm, :networks).and_return(networks)
+        expect(described_class).to receive(:replace_host)
+        expect(described_class).to_not receive(:add_hostname_to_loopback_interface)
+        described_class.change_host_name(machine, name)
+      end
+
+      it "appends an entry to the loopback interface" do 
+        networks = [
+          [:forwarded_port, {:guest=>22, :host=>2222, :host_ip=>"127.0.0.1", :id=>"ssh", :auto_correct=>true, :protocol=>"tcp"}],
+          [:public_network, {:ip=>"192.168.0.1", :protocol=>"tcp", :id=>"93a4ad88-0774-4127-a161-ceb715ff372f"}],
+          [:public_network, {:ip=>"192.168.0.2", :protocol=>"tcp", :id=>"5aebe848-7d85-4425-8911-c2003d924120"}]
+        ]
+        allow(machine).to receive_message_chain(:config, :vm, :networks).and_return(networks)
+        expect(described_class).to_not receive(:replace_host)
+        expect(described_class).to receive(:add_hostname_to_loopback_interface).once
+        described_class.change_host_name(machine, name)
+      end
     end
   end
 end