Implement `test_macro' recipe keyword

features/recipe_test_macro.feature

@@ -0,0 +1,52 @@
+Feature: `test_macro' recipe keyword
+
+  Scenario: declares a new test keyword
+    Given a recipe with:
+      """
+      test_macro :even? do |n|
+        n % 2 == 0
+      end
+
+      [1, 2].each do |n|
+        task "test_macro-even-#{n}" do
+          condition { even? n }
+          echo n
+        end
+      end
+      """
+    When I successfully execute the recipe
+    Then the output must contain "2"
+    And the output must not contain "1"
+
+  @sshd
+  Scenario: has access to core tests
+    Given a recipe with:
+      """
+      target 'some_host.test'
+
+      test_macro(:other_env?) { |k| env? k }
+
+      [:shell, :non_existent_var].each do |k|
+        task "test_macro-condition-#{k}" do
+          condition { other_env? k }
+          echo "#{k}_ok"
+        end
+      end
+      """
+    When I successfully execute the recipe
+    Then the output must contain "shell_ok"
+    Then the output must not contain "non_existent_var_ok"
+
+  Scenario: has access to other tests declared with `test_macro'
+    Given a recipe with:
+      """
+      test_macro(:one?)       { |e| e == 1 }
+      test_macro(:one_alias?) { |e| one? e }
+
+      task :test_macro_macro do
+        condition { one_alias? 1 }
+        echo 'one_alias_ok'
+      end
+      """
+    When I successfully execute the recipe
+    Then the output must contain "one_alias_ok"

lib/producer/core.rb

@@ -16,6 +16,7 @@ require 'producer/core/actions/file_writer'
 
 # condition tests (need to be defined before the condition DSL)
 require 'producer/core/test'
+require 'producer/core/tests/condition_test'
 require 'producer/core/tests/file_contains'
 require 'producer/core/tests/has_dir'
 require 'producer/core/tests/has_env'

lib/producer/core/condition.rb

@@ -2,9 +2,9 @@ module Producer
   module Core
     class Condition
       class << self
-        def evaluate(env, &block)
+        def evaluate(env, *args, &block)
           dsl = DSL.new(env, &block)
-          return_value = dsl.evaluate
+          return_value = dsl.evaluate *args
           Condition.new(dsl.tests, return_value)
         end
       end

lib/producer/core/condition/dsl.rb

@@ -3,12 +3,21 @@ module Producer
     class Condition
       class DSL
         class << self
-          def define_test(keyword, klass)
-            define_method(keyword) do |*args|
-              @tests << klass.new(@env, *args)
+          def define_test(keyword, test)
+            {
+              keyword         => false,
+              "no_#{keyword}" => true
+            }.each do |kw, negated|
+              define_method(kw) do |*args|
+                if test.respond_to? :call
+                  args  = [test, *args]
+                  klass = Tests::ConditionTest
+                else
+                  klass = test
+                end
+                t = klass.new(@env, *args, negated: negated)
+                @tests << t
               end
-            define_method("no_#{keyword}") do |*args|
-              @tests << klass.new(@env, *args, negated: true)
             end
           end
         end
@@ -29,8 +38,8 @@ module Producer
           @tests  = []
         end
 
-        def evaluate
-          instance_eval &@block
+        def evaluate(*args)
+          instance_exec *args, &@block
         end
       end
     end

lib/producer/core/recipe/dsl.rb

@@ -38,6 +38,10 @@ module Producer
           end
         end
 
+        def test_macro(name, dsl: Condition::DSL, &block)
+          dsl.define_test(name, block)
+        end
+
         def set(key, value)
           env[key] = value
         end

lib/producer/core/tests/condition_test.rb

@@ -0,0 +1,23 @@
+module Producer
+  module Core
+    module Tests
+      class ConditionTest < Test
+        def verify
+          condition.met?
+        end
+
+        def condition
+          Condition.evaluate(env, *condition_args, &condition_block)
+        end
+
+        def condition_args
+          arguments.drop 1
+        end
+
+        def condition_block
+          arguments.first
+        end
+      end
+    end
+  end
+end

spec/producer/core/condition/dsl_spec.rb

@@ -22,9 +22,9 @@ module Producer::Core
       end
 
       describe '.define_test' do
-        let(:some_test_class) { Test }
+        let(:some_test) { Test }
 
-        before { described_class.define_test(:some_test, some_test_class) }
+        before { described_class.define_test(:some_test, some_test) }
 
         it 'defines a new test keyword' do
           expect(dsl).to respond_to :some_test
@@ -41,19 +41,38 @@ module Producer::Core
 
           it 'registers the test with current env' do
             dsl.some_test
-            expect(dsl.tests.first.env).to be env
+            expect(dsl.tests.last.env).to be env
           end
 
           it 'registers the test with given arguments' do
             dsl.some_test :some, :args
-            expect(dsl.tests.first.arguments).to eq [:some, :args]
+            expect(dsl.tests.last.arguments).to eq [:some, :args]
+          end
+
+          context 'when given test is callable' do
+            let(:some_test) { proc {} }
+
+            before { dsl.some_test }
+
+            it 'registers a condition test' do
+              expect(dsl.tests.last).to be_a Tests::ConditionTest
+            end
+
+            it 'registers the test with given block' do
+              expect(dsl.tests.last.condition_block).to be some_test
+            end
+
+            it 'registers the test with given arguments' do
+              dsl.some_test :some, :args
+              expect(dsl.tests.last.condition_args).to eq [:some, :args]
+            end
           end
         end
 
         context 'when a negated test keyword is called' do
           it 'registers a negated test' do
             dsl.no_some_test
-            expect(dsl.tests.first).to be_negated
+            expect(dsl.tests.last).to be_negated
           end
         end
       end
@@ -81,6 +100,15 @@ module Producer::Core
         it 'returns the value returned by the assigned block' do
           expect(dsl.evaluate).to eq block.call
         end
+
+        context 'when arguments are given' do
+          let(:block) { proc { |e| throw e } }
+
+          it 'passes arguments as block parameters' do
+            expect { dsl.evaluate :some_argument }
+              .to throw_symbol :some_argument
+          end
+        end
       end
     end
   end

spec/producer/core/recipe/dsl_spec.rb

@@ -102,6 +102,16 @@ module Producer::Core
         end
       end
 
+      describe '#test_macro' do
+        it 'defines the new test' do
+          condition_dsl = double 'condition dsl'
+          test_block = proc {}
+          expect(condition_dsl)
+            .to receive(:define_test).with(:some_test, test_block)
+          dsl.test_macro(:some_test, dsl: condition_dsl, &test_block)
+        end
+      end
+
       describe '#set' do
         it 'registers a key/value pair in env registry' do
           dsl.set :some_key, :some_value

spec/producer/core/tests/condition_test_spec.rb

@@ -0,0 +1,55 @@
+require 'spec_helper'
+
+module Producer::Core
+  module Tests
+    describe ConditionTest do
+      let(:env)       { double 'env' }
+      let(:block)     { proc { true } }
+      let(:arguments) { [:some, :args] }
+      subject(:test)  { described_class.new(env, block, *arguments) }
+
+      it_behaves_like 'test'
+
+      describe '#verify' do
+        context 'when condition is met' do
+          it 'returns true' do
+            expect(test.verify).to be true
+          end
+        end
+
+        context 'when condition is not met' do
+          let(:block) { proc { false } }
+
+          it 'returns false' do
+            expect(test.verify).to be false
+          end
+        end
+      end
+
+      describe '#condition' do
+        it 'evaluates a conditon' do
+          expect(Condition).to receive(:evaluate).with(env, *arguments, &block)
+          test.condition
+        end
+
+        it 'returns the evaluated condition' do
+          condition = double 'condition'
+          allow(Condition).to receive(:evaluate) { condition }
+          expect(test.condition).to eq condition
+        end
+      end
+
+      describe '#condition_args' do
+        it 'returns arguments for condition' do
+          expect(test.condition_args).to eq arguments
+        end
+      end
+
+      describe '#condition_block' do
+        it 'returns condition block' do
+          expect(test.condition_block).to eq block
+        end
+      end
+    end
+  end
+end