Add a new class for run control file evaluation

lib/uh/wm.rb

@@ -7,6 +7,7 @@ require 'uh/wm/cli'
 require 'uh/wm/dispatcher'
 require 'uh/wm/env'
 require 'uh/wm/manager'
+require 'uh/wm/run_control'
 require 'uh/wm/runner'
 
 module Uh

lib/uh/wm/run_control.rb

@@ -0,0 +1,21 @@
+module Uh
+  module WM
+    class RunControl
+      class << self
+        def evaluate env
+          rc_path = File.expand_path(env.rc_path)
+          rc = new env
+          rc.evaluate File.read(rc_path) if File.exist?(rc_path)
+        end
+      end
+
+      def initialize env
+        @env = env
+      end
+
+      def evaluate code
+        instance_eval code
+      end
+    end
+  end
+end

lib/uh/wm/runner.rb

@@ -32,8 +32,7 @@ module Uh
       end
 
       def evaluate_run_control
-        rc_path = File.expand_path(@env.rc_path)
-        eval File.read(rc_path) if File.exist?(rc_path)
+        RunControl.evaluate(env)
       end
 
       def register_event_hooks

spec/uh/wm/run_control_spec.rb

@@ -0,0 +1,53 @@
+require 'support/filesystem_helpers'
+
+module Uh
+  module WM
+    RSpec.describe RunControl do
+      include FileSystemHelpers
+
+      let(:code)    { :run_control_code }
+      let(:env)     { Env.new(StringIO.new) }
+      subject(:rc)  { described_class.new env }
+
+      describe '.evaluate' do
+        around do |example|
+          with_file ':run_control_code' do |f|
+            env.rc_path = f.path
+            example.run
+          end
+        end
+
+        it 'builds a new instance with given env' do
+          expect(described_class).to receive(:new).with(env).and_call_original
+          described_class.evaluate env
+        end
+
+        it 'tells the new instance to evaluate run control file content' do
+          expect(rc).to receive(:evaluate).with ':run_control_code'
+          allow(described_class).to receive(:new) { rc }
+          described_class.evaluate env
+        end
+
+        context 'when run control file is not present' do
+          before { env.rc_path = 'non_existent_rc_file.rb' }
+
+          it 'does not raise any error' do
+            expect { described_class.evaluate env }.not_to raise_error
+          end
+        end
+      end
+
+      describe '#evaluate' do
+        it 'evaluates given code' do
+          expect { rc.evaluate 'throw :run_control_code' }
+            .to throw_symbol :run_control_code
+        end
+
+        it 'provides access to assigned env' do
+          expect { rc.evaluate 'fail @env.object_id.to_s' }
+            .to raise_error env.object_id.to_s
+        end
+      end
+    end
+  end
+end

spec/uh/wm/runner_spec.rb

@@ -1,5 +1,3 @@
-require 'support/filesystem_helpers'
-
 SomeLayout = Class.new do
   define_method(:register) { |*args| }
 end
@@ -7,8 +5,6 @@ end
 module Uh
   module WM
     RSpec.describe Runner do
-      include FileSystemHelpers
-
       let(:env)         { Env.new(StringIO.new) }
       subject(:runner)  { described_class.new env }
 
@@ -60,19 +56,9 @@ module Uh
       end
 
       describe '#evaluate_run_control' do
-        context 'when run control file is present' do
-          it 'evaluates the run control file' do
-            with_file 'throw :run_control' do |f|
-              env.rc_path = f.path
-              expect { runner.evaluate_run_control }.to throw_symbol :run_control
-            end
-          end
-        end
-
-        context 'when run control file is not present' do
-          it 'does not raise any error' do
-            expect { runner.evaluate_run_control }.not_to raise_error
-          end
+        it 'evaluates the run control file with RunControl and current env' do
+          expect(RunControl).to receive(:evaluate).with env
+          runner.evaluate_run_control
         end
       end