Implement `yaml_eq' condition keyword

features/test_yaml_eq.feature

@@ -0,0 +1,26 @@
+@sshd
+Feature: `yaml_eq' condition keyword
+
+  Background:
+    Given a recipe with:
+      """
+      task :yaml_eq_test do
+        condition { yaml_eq 'some_file', { foo: 'bar' } }
+
+        echo 'evaluated'
+      end
+      """
+
+  Scenario: succeeds when YAML data is equivalent
+    Given a remote file named "some_file" with ":foo: bar"
+    When I successfully execute the recipe on remote target
+    Then the output must contain "evaluated"
+
+  Scenario: fails when YAML data differs
+    Given a remote file named "some_file" with ":foo: baz"
+    When I successfully execute the recipe on remote target
+    Then the output must not contain "evaluated"
+
+  Scenario: fails when YAML file does not exist
+    When I successfully execute the recipe on remote target
+    Then the output must not contain "evaluated"

lib/producer/core.rb

@@ -30,6 +30,7 @@ require 'producer/core/tests/has_env'
 require 'producer/core/tests/has_executable'
 require 'producer/core/tests/has_file'
 require 'producer/core/tests/shell_command_status'
+require 'producer/core/tests/yaml_eq'
 
 require 'producer/core/cli'
 require 'producer/core/condition'

lib/producer/core/condition.rb

@@ -41,6 +41,7 @@ module Producer
       define_test :executable?,     Tests::HasExecutable
       define_test :dir?,            Tests::HasDir
       define_test :file?,           Tests::HasFile
+      define_test :yaml_eq,         Tests::YAMLEq
 
       attr_reader :tests, :return_value
 

lib/producer/core/tests/yaml_eq.rb

@@ -0,0 +1,12 @@
+module Producer
+  module Core
+    module Tests
+      class YAMLEq < Test
+        def verify
+          return false unless file_content = fs.file_read(arguments.first)
+          YAML.load(file_content) == arguments[1]
+        end
+      end
+    end
+  end
+end

spec/producer/core/tests/yaml_eq_spec.rb

@@ -0,0 +1,47 @@
+require 'spec_helper'
+
+module Producer::Core
+  module Tests
+    describe YAMLEq, :env do
+      let(:filepath)  { 'some_file' }
+      let(:data)      { { foo: 'bar' } }
+      subject(:test)  { described_class.new(env, filepath, data, {}) }
+
+      it_behaves_like 'test'
+
+      describe '#verify' do
+        context 'when file content matches' do
+          before do
+            allow(remote_fs)
+              .to receive(:file_read).with(filepath) { ':foo: bar' }
+          end
+
+          it 'returns true' do
+            expect(test.verify).to be true
+          end
+        end
+
+        context 'when file content does not match' do
+          before do
+            allow(remote_fs)
+              .to receive(:file_read).with(filepath) { ':foo: baz' }
+          end
+
+          it 'returns false' do
+            expect(test.verify).to be false
+          end
+        end
+
+        context 'when file does not exist' do
+          before do
+            allow(remote_fs).to receive(:file_read).with(filepath) { nil }
+          end
+
+          it 'returns false' do
+            expect(test.verify).to be false
+          end
+        end
+      end
+    end
+  end
+end