Implement `file_replace_content' task action

features/actions/file_replace_content.feature

@@ -0,0 +1,31 @@
+@sshd
+Feature: `file_replace_content' task action
+
+  Background:
+    Given a remote file named "some_file" with "some content"
+
+  Scenario: replace a string by another in the requested file
+    Given a recipe with:
+      """
+      target 'some_host.test'
+
+      task :replace_string_in_file do
+        file_replace_content 'some_file', 'content', 'other content'
+      end
+      """
+    When I execute the recipe
+    Then the exit status must be 0
+    And the remote file "some_file" must contain exactly "some other content"
+
+  Scenario: replace a regular expression by a string in the requested file
+    Given a recipe with:
+      """
+      target 'some_host.test'
+
+      task :replace_string_in_file do
+        file_replace_content 'some_file', /\w+\z/, 'other content'
+      end
+      """
+    When I execute the recipe
+    Then the exit status must be 0
+    And the remote file "some_file" must contain exactly "some other content"

features/steps/remote_steps.rb

@@ -17,3 +17,7 @@ end
 Then /^the remote file "([^"]+)" should contain "([^"]+)"/ do |path, content|
   check_file_content path, content, true
 end
+
+Then /^the remote file "([^"]+)" should contain exactly "([^"]+)"/ do |path, content|
+  check_exact_file_content path, content
+end

lib/producer/core.rb

@@ -10,6 +10,7 @@ require 'producer/core/action'
 require 'producer/core/actions/echo'
 require 'producer/core/actions/shell_command'
 require 'producer/core/actions/mkdir'
+require 'producer/core/actions/file_replace_content'
 require 'producer/core/actions/file_writer'
 
 # condition tests (need to be defined before the condition DSL)

lib/producer/core/actions/file_replace_content.rb

@@ -0,0 +1,27 @@
+module Producer
+  module Core
+    module Actions
+      class FileReplaceContent < Action
+        def apply
+          fs.file_write path, replaced_content
+        end
+
+        def path
+          arguments[0]
+        end
+
+        def pattern
+          arguments[1]
+        end
+
+        def replacement
+          arguments[2]
+        end
+
+        def replaced_content
+          fs.file_read(path).gsub pattern, replacement
+        end
+      end
+    end
+  end
+end

lib/producer/core/task/dsl.rb

@@ -15,6 +15,7 @@ module Producer
 
         define_action :mkdir,                 Actions::Mkdir
         define_action :file_write,            Actions::FileWriter
+        define_action :file_replace_content,  Actions::FileReplaceContent
 
         attr_reader :env, :block, :actions
 

spec/producer/core/actions/file_replace_content_spec.rb

@@ -0,0 +1,49 @@
+require 'spec_helper'
+
+module Producer::Core
+  module Actions
+    describe FileReplaceContent, :env do
+      let(:path)        { 'some_path' }
+      let(:pattern)     { 'content' }
+      let(:replacement) { 'other content' }
+      let(:content)     { 'some content' }
+      subject(:action)  { FileReplaceContent.new(env, path, pattern, replacement) }
+
+      it_behaves_like 'action'
+
+      before { allow(remote_fs).to receive(:file_read).with(path) { content } }
+
+      describe '#apply' do
+        it 'writes replaced content to file on remote filesystem' do
+          expect(remote_fs)
+            .to receive(:file_write).with(path, action.replaced_content)
+          action.apply
+        end
+      end
+
+      describe '#path' do
+        it 'returns the file path' do
+          expect(action.path).to eq path
+        end
+      end
+
+      describe '#pattern' do
+        it 'returns the pattern' do
+          expect(action.pattern).to eq pattern
+        end
+      end
+
+      describe '#replacement' do
+        it 'returns the replacement' do
+          expect(action.replacement).to eq replacement
+        end
+      end
+
+      describe '#replaced_content' do
+        it 'returns content with pattern occurrences pattern replaced' do
+          expect(action.replaced_content).to eq 'some other content'
+        end
+      end
+    end
+  end
+end

spec/producer/core/task/dsl_spec.rb

@@ -7,7 +7,7 @@ module Producer::Core
       let(:env)     { Env.new }
       subject(:dsl) { DSL.new(env, &block) }
 
-      %w[echo sh mkdir file_write].each do |action|
+      %w[echo sh mkdir file_write file_replace_content].each do |action|
         it "has `#{action}' action defined" do
           expect(dsl).to respond_to action.to_sym
         end