Refactor Recipe specs:

* Use more classic specs for .evaluate_from_file;
* Fix coding standards.

spec/producer/core/recipe_spec.rb

@@ -7,35 +7,13 @@ module Producer::Core
     subject(:recipe) { Recipe.new }
 
     describe '.evaluate_from_file' do
-      let(:env)       { double 'env' }
+      let(:env)         { double 'env' }
-      let(:filepath)  { fixture_path_for 'recipes/empty.rb' }
+      let(:filepath)    { fixture_path_for 'recipes/some_recipe.rb' }
-      let(:code)      { File.read(filepath) }
+      subject(:recipe)  { Recipe.evaluate_from_file(filepath, env) }
 
-      it 'builds a new DSL sandbox with code read from given file path' do
+      it 'returns an evaluated recipe' do
-        expect(Recipe::DSL).to receive(:new).with(code).and_call_original
+        expect(recipe.tasks.map(&:name)).to eq [:some_task, :another_task]
-        Recipe.evaluate_from_file(filepath, env)
       end
-
-      it 'evaluates the DSL sandbox code with given environment' do
-        dsl = double('dsl').as_null_object
-        allow(Recipe::DSL).to receive(:new) { dsl }
-        expect(dsl).to receive(:evaluate).with(env)
-        Recipe.evaluate_from_file(filepath, env)
-      end
-
-      it 'builds a recipe with evaluated tasks' do
-        dsl = Recipe::DSL.new { task(:some_task) { } }
-        allow(Recipe::DSL).to receive(:new) { dsl }
-        expect(Recipe).to receive(:new).with(dsl.tasks)
-        Recipe.evaluate_from_file(filepath, env)
-      end
-
-      it 'returns the recipe' do
-        recipe = double('recipe').as_null_object
-        allow(Recipe).to receive(:new) { recipe }
-        expect(Recipe.evaluate_from_file(filepath, env)).to be recipe
-      end
-
     end
 
     describe '#initialize' do
@@ -46,8 +24,8 @@ module Producer::Core
       end
 
       context 'when tasks are given as argument' do
-        let(:tasks)   { [Task.new(:some_task)] }
+        let(:tasks)       { [double('task')] }
-        let(:recipe)  { Recipe.new(tasks) }
+        subject(:recipe)  { Recipe.new(tasks) }
 
         it 'assigns the tasks' do
           expect(recipe.tasks).to eq tasks