core: has_plugin? uses the new plugin manager class to check for gems

lib/vagrant.rb

@@ -147,10 +147,12 @@ module Vagrant
   # be used from the Vagrantfile to easily branch based on plugin
   # availability.
   def self.has_plugin?(name)
-    manager = plugin("2").manager
+    # We check the plugin names first because those are cheaper to check
+    return true if plugin("2").manager.registered.any? { |p| p.name == name }
 
-    manager.required.any? { |gem_name| gem_name == name } ||
-      manager.registered.any? { |plugin| plugin.name == name }
+    # Now check the plugin gem names
+    require "vagrant/plugin/manager"
+    Plugin::Manager.instance.installed_specs.any? { |s| s.name == name }
   end
 
   # Returns a superclass to use when creating a plugin for Vagrant.

lib/vagrant/plugin/v2/manager.rb

@@ -8,12 +8,10 @@ module Vagrant
       # those plugins as a single unit.
       class Manager
         attr_reader :registered
-        attr_reader :required
 
         def initialize
           @logger = Log4r::Logger.new("vagrant::plugin::v2::manager")
           @registered = []
-          @required = []
         end
 
         # This returns all the action hooks.
@@ -182,20 +180,10 @@ module Vagrant
           end
         end
 
-        # This registers a required plugin. This should _NEVER_ be called by
-        # the public and should only be called from within Vagrant.
-        def plugin_required(gem_name)
-          if !@required.include?(gem_name)
-            @logger.info("Registered required plugin: #{gem_name}")
-            @required << gem_name
-          end
-        end
-
         # This clears out all the registered plugins. This is only used by
         # unit tests and should not be called directly.
         def reset!
           @registered.clear
-          @required.clear
         end
 
         # This unregisters a plugin so that its components will no longer

test/unit/vagrant/plugin/v2/manager_test.rb

@@ -205,16 +205,4 @@ describe Vagrant::Plugin::V2::Manager do
     instance.synced_folders[:foo].should == ["bar", 10]
     instance.synced_folders[:bar].should == ["baz", 50]
   end
-
-  it "should list the required plugins" do
-    instance.plugin_required("foo")
-    instance.plugin_required("bar")
-    expect(instance.required).to eq(["foo", "bar"])
-  end
-
-  it "should list the required plugins only once" do
-    instance.plugin_required("foo")
-    instance.plugin_required("foo")
-    expect(instance.required).to eq(["foo"])
-  end
 end

test/unit/vagrant_test.rb

@@ -48,28 +48,32 @@ describe Vagrant do
   end
 
   describe "has_plugin?" do
-    before(:each) do
-      Class.new(described_class.plugin("2")) do
-        name "i_am_installed"
-      end
-      manager.plugin_required("plugin_gem")
-    end
     after(:each) do
       manager.reset!
     end
+
     let(:manager) { described_class.plugin("2").manager }
 
-    it "should find the installed plugin by the gem name" do
-      expect(described_class.has_plugin?("plugin_gem")).to be_true
-    end
-
     it "should find the installed plugin by the registered name" do
+      Class.new(described_class.plugin(Vagrant::Config::CURRENT_VERSION)) do
+        name "i_am_installed"
+      end
+
       expect(described_class.has_plugin?("i_am_installed")).to be_true
     end
 
     it "should return false if the plugin is not installed" do
       expect(described_class.has_plugin?("i_dont_exist")).to be_false
     end
+
+    it "finds plugins by gem name" do
+      specs = [Gem::Specification.new]
+      specs[0].name = "foo"
+      Vagrant::Plugin::Manager.instance.stub(:installed_specs => specs)
+
+      expect(described_class.has_plugin?("foo")).to be_true
+      expect(described_class.has_plugin?("bar")).to be_false
+    end
   end
 
   describe "require_version" do