provisioners/docker: configuration is mergeable

plugins/provisioners/docker/config.rb

@@ -3,14 +3,25 @@ require 'set'
 module VagrantPlugins
   module Docker
     class Config < Vagrant.plugin("2", :config)
-      attr_reader :build_images, :images, :containers, :build_options
+      attr_reader :images
       attr_accessor :version
 
       def initialize
         @images         = Set.new
-        @containers     = Hash.new
         @version        = UNSET_VALUE
-        @build_images   = []
+
+        @__build_images   = []
+        @__containers     = Hash.new { |h, k| h[k] = {} }
+      end
+
+      # Accessor for internal state.
+      def build_images
+        @__build_images
+      end
+
+      # Accessor for the internal state.
+      def containers
+        @__containers
       end
 
       # Defines an image to build using `docker build` within the machine.
@@ -18,7 +29,7 @@ module VagrantPlugins
       # @param [String] path Path to the Dockerfile to pass to
       #   `docker build`.
       def build_image(path, **opts)
-        @build_images << [path, opts]
+        @__build_images << [path, opts]
       end
 
       def images=(images)
@@ -30,22 +41,36 @@ module VagrantPlugins
       end
 
       def run(name, **options)
-        params = options.dup
+        @__containers[name.to_s] = options.dup
-        params[:image] ||= name
-        params[:daemonize] = true if !params.has_key?(:daemonize)
-
-        # TODO: Validate provided parameters before assignment
-        @containers[name.to_s] = params
-      end
-
-      def finalize!
-        @version = "latest" if @version == UNSET_VALUE
-        @version = @version.to_sym
       end
 
       def merge(other)
         super.tap do |result|
           result.pull_images(*(other.images + self.images))
+
+          build_images = @__build_images.dup
+          build_images += other.build_images
+          result.instance_variable_set(:@__build_images, build_images)
+
+          containers = {}
+          @__containers.each do |name, params|
+            containers[name] = params.dup
+          end
+          other.containers.each do |name, params|
+            containers[name] = @__containers[name].merge(params)
+          end
+
+          result.instance_variable_set(:@__containers, containers)
+        end
+      end
+
+      def finalize!
+        @version = "latest" if @version == UNSET_VALUE
+        @version = @version.to_sym
+
+        @__containers.each do |name, params|
+          params[:image] ||= name
+          params[:daemonize] = true if !params.has_key?(:daemonize)
         end
       end
     end

test/unit/plugins/provisioners/docker/config_test.rb

@@ -31,6 +31,56 @@ describe VagrantPlugins::Docker::Config do
     end
   end
 
+  describe "#merge" do
+    it "has all images to pull" do
+      subject.pull_images("1")
+
+      other = described_class.new
+      other.pull_images("2", "3")
+
+      result = subject.merge(other)
+      expect(result.images.to_a.sort).to eq(
+        ["1", "2", "3"])
+    end
+
+    it "has all the containers to run" do
+      subject.run("foo", image: "bar", daemonize: false)
+      subject.run("bar")
+
+      other = described_class.new
+      other.run("foo", image: "foo")
+
+      result = subject.merge(other)
+      result.finalize!
+
+      cs     = result.containers
+      expect(cs.length).to eq(2)
+      expect(cs["foo"]).to eq({
+        image: "foo",
+        daemonize: false,
+      })
+      expect(cs["bar"]).to eq({
+        image: "bar",
+        daemonize: true,
+      })
+    end
+
+    it "has all the containers to build" do
+      subject.build_image("foo")
+
+      other = described_class.new
+      other.build_image("bar")
+
+      result = subject.merge(other)
+      result.finalize!
+
+      images = result.build_images
+      expect(images.length).to eq(2)
+      expect(images[0]).to eq(["foo", {}])
+      expect(images[1]).to eq(["bar", {}])
+    end
+  end
+
   describe "#pull_images" do
     it "adds images to the list of images to build" do
       subject.pull_images("1")