Build conditions with DSL evaluated tests:

In Condition:

  * Modify constructor to accepts tests and a default return value;
  * Implement #met?;
  * Modify #! so that it return the negated value returned by #met?.

  In Condition::DSL:

  * Modify .evaluate to build the condition with tests and the value
    returned by a the evaluated condition block.

  Add a basic Test base class, with env and arguments as attributes.

  Add some spec helpers to build some easily testable kind of Test
instances (as test doubles).

spec/producer/core/test_spec.rb

@@ -0,0 +1,30 @@
+require 'spec_helper'
+
+module Producer::Core
+  describe Test do
+    let(:env)         { double 'env' }
+    let(:arguments)   { [:some, :arguments] }
+    subject(:action)  { Test.new(env, *arguments) }
+
+    describe '#initialize' do
+      it 'assigns the env' do
+        expect(action.instance_eval { @env }).to be env
+      end
+      it 'assigns the arguments' do
+        expect(action.instance_eval { @arguments }).to eq arguments
+      end
+    end
+
+    describe '#env' do
+      it 'returns the assigned env' do
+        expect(action.env).to be env
+      end
+    end
+
+    describe '#arguments' do
+      it 'returns the assigned arguments' do
+        expect(action.arguments).to eq arguments
+      end
+    end
+  end
+end