Implement `file_contains' condition keyword

features/steps/remote_steps.rb

@@ -6,6 +6,10 @@ Given /^a remote file named "([^"]+)"$/ do |file_name|
   write_file file_name, ''
 end
 
+Given /^a remote file named "([^"]+)" with "([^"]+)"$/ do |file_name, content|
+  write_file file_name, content
+end
+
 Then /^the remote directory "([^"]+)" should exists$/ do |path|
   check_directory_presence([path], true)
 end

features/tests/file_contains.feature

@@ -0,0 +1,28 @@
+@sshd
+Feature: `file_contains' condition keyword
+
+  Background:
+    Given a recipe with:
+      """
+      target 'some_host.test'
+
+      task :testing_content_in_file_presense do
+        condition { file_contains 'some_file', 'some_content' }
+
+        echo 'evaluated'
+      end
+      """
+
+  Scenario: succeeds when file contains expected content
+    Given a remote file named "some_file" with "some_content"
+    When I successfully execute the recipe
+    Then the output must contain "evaluated"
+
+  Scenario: fails when file does not contain expected content
+    Given a remote file named "some_file" with "some_other_content"
+    When I successfully execute the recipe
+    Then the output must not contain "evaluated"
+
+  Scenario: fails when file does not exist
+    When I successfully execute the recipe
+    Then the output must not contain "evaluated"

lib/producer/core.rb

@@ -9,6 +9,7 @@ require 'producer/core/actions/file_writer'
 
 # condition tests (need to be defined before the condition DSL)
 require 'producer/core/test'
+require 'producer/core/tests/file_contains'
 require 'producer/core/tests/has_dir'
 require 'producer/core/tests/has_env'
 require 'producer/core/tests/has_file'

lib/producer/core/condition/dsl.rb

@@ -13,9 +13,10 @@ module Producer
           end
         end
 
-        define_test :has_env,   Tests::HasEnv
-        define_test :has_dir,   Tests::HasDir
-        define_test :has_file,  Tests::HasFile
+        define_test :file_contains, Tests::FileContains
+        define_test :has_env,       Tests::HasEnv
+        define_test :has_dir,       Tests::HasDir
+        define_test :has_file,      Tests::HasFile
 
         attr_reader :block, :env, :tests
 

lib/producer/core/tests/file_contains.rb

@@ -0,0 +1,18 @@
+module Producer
+  module Core
+    module Tests
+      class FileContains < Test
+        def verify
+          content = file_content
+          content ? content.include?(arguments[1]) : false
+        end
+
+        private
+
+        def file_content
+          fs.file_read(arguments[0])
+        end
+      end
+    end
+  end
+end

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_dir has_env has_file].each do |test|
+    %w[file_contains 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/file_contains_spec.rb

@@ -0,0 +1,44 @@
+require 'spec_helper'
+
+module Producer::Core
+  describe Tests::FileContains do
+    let(:env)       { Env.new }
+    let(:filepath)  { 'some_file' }
+    let(:content)   { 'some_content' }
+    subject(:test)  { Tests::FileContains.new(env, filepath, content) }
+
+    it 'is a kind of test' do
+      expect(test).to be_a Test
+    end
+
+    describe '#verify' do
+      let(:fs) { double 'fs' }
+
+      before { allow(test).to receive(:fs) { fs } }
+
+      context 'when file contains the content' do
+        before { allow(fs).to receive(:file_read).with(filepath) { "foo#{content}bar" } }
+
+        it 'returns true' do
+          expect(test.verify).to be true
+        end
+      end
+
+      context 'when file does not contain the content' do
+        before { allow(fs).to receive(:file_read).with(filepath) { 'foo bar' } }
+
+        it 'returns false' do
+          expect(test.verify).to be false
+        end
+      end
+
+      context 'when file does not exist' do
+        before { allow(fs).to receive(:file_read).with(filepath) { nil } }
+
+        it 'returns false' do
+          expect(test.verify).to be false
+        end
+      end
+    end
+  end
+end