Implement ruby feature loading (-r CLI option)

features/cli/ruby_features.feature

@@ -0,0 +1,5 @@
+Feature: ruby feature require CLI option
+
+  Scenario: requires a ruby feature
+    When I run uhwm with option -v -r abbrev
+    Then the current output must match /load.+abbrev.+ruby feature/i

features/steps/output_steps.rb

@@ -23,6 +23,7 @@ options:
     -h, --help                       print this message
     -v, --version                    enable verbose mode
     -d, --debug                      enable debug mode
+    -r, --require PATH               require ruby feature
   eoh
 end
 

lib/uh/wm/cli.rb

@@ -58,6 +58,11 @@ module Uh
             @env.debug = true
             @env.log_logger_level
           end
+
+          opts.on '-r', '--require PATH', 'require ruby feature' do |feature|
+            require feature
+            @env.log "Loaded `#{feature}' ruby feature"
+          end
         end
       end
     end

spec/uh/wm/cli_spec.rb

@@ -116,6 +116,21 @@ module Uh
           end
         end
 
+        context 'with require option' do
+          let(:arguments) { %w[-r abbrev] }
+
+          it 'requires the given ruby feature' do
+            expect { cli.parse_arguments! }
+              .to change { $LOADED_FEATURES.grep(/abbrev/).any? }
+              .from(false).to(true)
+          end
+
+          it 'logs a message about the feature being loaded' do
+            expect(cli.env).to receive(:log).with /load.+abbrev.+ruby feature/i
+            cli.parse_arguments!
+          end
+        end
+
         context 'with invalid option' do
           let(:arguments) { %w[--unknown-option] }