Implement `has_dir' condition keyword

spec/producer/core/condition/dsl_spec.rb

@@ -6,7 +6,7 @@ module Producer::Core
     let(:env)     { double 'env' }
     subject(:dsl) { Condition::DSL.new(env, &block) }
 
-    %w[has_env has_file].each do |test|
+    %w[has_dir has_env has_file].each do |test|
       it "has `#{test}' test defined" do
         expect(dsl).to respond_to test.to_sym
       end

spec/producer/core/tests/has_dir_spec.rb

@@ -0,0 +1,28 @@
+require 'spec_helper'
+
+module Producer::Core
+  describe Tests::HasDir do
+    let(:env)         { Env.new }
+    let(:path)        { 'some_directory' }
+    subject(:has_dir) { Tests::HasDir.new(env, path) }
+
+    it 'is a kind of test' do
+      expect(has_dir).to be_a Test
+    end
+
+    describe '#verify', :ssh do
+      before { sftp_story }
+
+      it 'delegates the call on remote FS' do
+        expect(env.remote.fs).to receive(:dir?).with(path)
+        has_dir.verify
+      end
+
+      it 'returns the dir existence' do
+        existence = double 'existence'
+        allow(env.remote.fs).to receive(:dir?) { existence }
+        expect(has_dir.verify).to be existence
+      end
+    end
+  end
+end