Implement `file_match' condition keyword

features/test_file_match.feature

@@ -0,0 +1,26 @@
+@sshd
+Feature: `file_match' condition keyword
+
+  Background:
+    Given a recipe with:
+      """
+      task :file_match_test do
+        condition { file_match 'some_file', /\Asome_content\z/ }
+
+        echo 'evaluated'
+      end
+      """
+
+  Scenario: succeeds when file match pattern
+    Given a remote file named "some_file" with "some_content"
+    When I successfully execute the recipe on remote target
+    Then the output must contain "evaluated"
+
+  Scenario: fails when file does not match pattern
+    Given a remote file named "some_file" with "some_other_content"
+    When I successfully execute the recipe on remote target
+    Then the output must not contain "evaluated"
+
+  Scenario: fails when file does not exist
+    When I successfully execute the recipe on remote target
+    Then the output must not contain "evaluated"

lib/producer/core.rb

@@ -21,6 +21,7 @@ require 'producer/core/test'
 require 'producer/core/tests/condition_test'
 require 'producer/core/tests/file_contains'
 require 'producer/core/tests/file_eq'
+require 'producer/core/tests/file_match'
 require 'producer/core/tests/has_dir'
 require 'producer/core/tests/has_env'
 require 'producer/core/tests/has_executable'

lib/producer/core/condition.rb

@@ -36,6 +36,7 @@ module Producer
       define_test :sh,              Tests::ShellCommandStatus
       define_test :file_contains,   Tests::FileContains
       define_test :file_eq,         Tests::FileEq
+      define_test :file_match,      Tests::FileMatch
       define_test :env?,            Tests::HasEnv
       define_test :executable?,     Tests::HasExecutable
       define_test :dir?,            Tests::HasDir

lib/producer/core/tests/file_match.rb

@@ -0,0 +1,18 @@
+module Producer
+  module Core
+    module Tests
+      class FileMatch < Test
+        def verify
+          !!(file_content =~ arguments[1])
+        end
+
+
+        private
+
+        def file_content
+          fs.file_read(arguments[0]) or ''
+        end
+      end
+    end
+  end
+end

spec/producer/core/condition_spec.rb

@@ -9,6 +9,7 @@ module Producer::Core
       sh
       file_contains
       file_eq
+      file_match
       dir?
       env?
       executable?

spec/producer/core/tests/file_match_spec.rb

@@ -0,0 +1,46 @@
+require 'spec_helper'
+
+module Producer::Core
+  module Tests
+    describe FileMatch, :env do
+      let(:filepath)  { 'some_file' }
+      let(:pattern)   { /\Asome_content\z/ }
+      subject(:test)  { described_class.new(env, filepath, pattern) }
+
+      it_behaves_like 'test'
+
+      describe '#verify' do
+        context 'when file matches the pattern' do
+          before do
+            allow(remote_fs)
+              .to receive(:file_read).with(filepath) { 'some_content' }
+          end
+
+          it 'returns true' do
+            expect(test.verify).to be true
+          end
+        end
+
+        context 'when file does not match the pattern' do
+          before do
+            allow(remote_fs).to receive(:file_read).with(filepath) { 'foo bar' }
+          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