Add CentOS guest plugin

plugins/guests/centos/cap/flavor.rb

@@ -0,0 +1,24 @@
+module VagrantPlugins
+  module GuestCentos
+    module Cap
+      class Flavor
+        def self.flavor(machine)
+          # Read the version file
+          output = ""
+          machine.communicate.sudo("cat /etc/centos-release") do |_, data|
+            output = data
+          end
+
+          # Detect various flavors we care about
+          if output =~ /(CentOS)( .+)? 7/i
+            return :centos_7
+          elsif output =~ /(CentOS)( .+)? 8/i
+            return :centos_8
+          else
+            return :centos
+          end
+        end
+      end
+    end
+  end
+end

plugins/guests/centos/guest.rb

@@ -0,0 +1,9 @@
+module VagrantPlugins
+  module GuestCentos
+    class Guest < Vagrant.plugin("2", :guest)
+      def detect?(machine)
+        machine.communicate.test("cat /etc/centos-release")
+      end
+    end
+  end
+end

plugins/guests/centos/plugin.rb

@@ -0,0 +1,20 @@
+require "vagrant"
+
+module VagrantPlugins
+  module GuestCentos
+    class Plugin < Vagrant.plugin("2")
+      name "CentOS guest"
+      description "CentOS guest support."
+
+      guest(:centos, :redhat) do
+        require_relative "guest"
+        Guest
+      end
+
+      guest_capability(:centos, :flavor) do
+        require_relative "cap/flavor"
+        Cap::Flavor
+      end
+    end
+  end
+end

plugins/guests/redhat/cap/flavor.rb

@@ -10,13 +10,7 @@ def self.flavor(machine)
           end
 
           # Detect various flavors we care about
-          if output =~ /(CentOS)( .+)? 7/i
-            return :centos_7
-          elsif output =~ /(CentOS)( .+)? 8/i
-            return :centos_8
-          elsif output =~ /(CentOS)( .+)?/i
-            return :centos
-          elsif output =~ /(Red Hat Enterprise|Scientific|Cloud|Virtuozzo)\s*Linux( .+)? release 7/i
+          if output =~ /(Red Hat Enterprise|Scientific|Cloud|Virtuozzo)\s*Linux( .+)? release 7/i
             return :rhel_7
           elsif output =~ /(Red Hat Enterprise|Scientific|Cloud|Virtuozzo)\s*Linux( .+)? release 8/i
             return :rhel_8

test/unit/plugins/guests/centos/cap/flavor_test.rb

@@ -0,0 +1,37 @@
+require_relative "../../../../base"
+
+describe "VagrantPlugins::GuestCentos::Cap::Flavor" do
+  let(:caps) do
+    VagrantPlugins::GuestCentos::Plugin
+      .components
+      .guest_capabilities[:centos]
+  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 ".flavor" do
+    let(:cap) { caps.get(:flavor) }
+
+    {
+      "CentOS Linux 2.4 release 7" => :centos_7,
+      "CentOS Linux release 8.1.1911 (Core)" => :centos_8,
+
+      "CentOS" => :centos,
+      "banana" => :centos,
+    }.each do |str, expected|
+      it "returns #{expected} for #{str}" do
+        comm.stub_command("cat /etc/centos-release", stdout: str)
+        expect(cap.flavor(machine)).to be(expected)
+      end
+    end
+  end
+end

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

@@ -22,15 +22,15 @@
     let(:cap) { caps.get(:flavor) }
 
     {
-      "CentOS Linux 2.4 release 7" => :centos_7,
+      "Red Hat Enterprise Linux 2.4 release 7" => :rhel_7,
       "Red Hat Enterprise Linux release 7" => :rhel_7,
       "Scientific Linux release 7" => :rhel_7,
       "CloudLinux release 7.2 (Valeri Kubasov)" => :rhel_7,
 
-      "CentOS Linux release 8.1.1911 (Core)" => :centos_8,
+      "CloudLinux release 8.1.1911 (Valeri Kubasov)" => :rhel_8,
       "Red Hat Enterprise Linux release 8" => :rhel_8,
 
-      "CentOS" => :centos,
+      "Red Hat Enterprise Linux" => :rhel,
       "RHEL 6" => :rhel,
       "banana" => :rhel,
     }.each do |str, expected|