Extracted common behaviour from SSHStdinAdapter and LocalStdinAdapter…

… to ExternalProcessAdapter class

lib/remote_ruby/connection_adapter.rb

@@ -21,7 +21,8 @@ def open(_code)
 end
 
 require 'remote_ruby/connection_adapter/eval_adapter.rb'
-require 'remote_ruby/connection_adapter/local_stdin_adapter'
+require 'remote_ruby/connection_adapter/external_process_adapter'
 require 'remote_ruby/connection_adapter/ssh_stdin_adapter'
+require 'remote_ruby/connection_adapter/local_stdin_adapter'
 require 'remote_ruby/connection_adapter/cache_adapter'
 require 'remote_ruby/connection_adapter/caching_adapter'

lib/remote_ruby/connection_adapter/external_process_adapter.rb

@@ -0,0 +1,31 @@
+require 'open3'
+
+module RemoteRuby
+  # Base class for adapters which launch an external process to execute
+  # Ruby code.
+  class ExternalProcessAdapter < ::RemoteRuby::ConnectionAdapter
+    include Open3
+
+    # Command to run an external process. Override in a child class.
+    def command
+      raise NotImplementedError
+    end
+
+    def open(code)
+      result = nil
+
+      popen3(command) do |stdin, stdout, stderr, wait_thr|
+        stdin.write(code)
+        stdin.close
+
+        yield stdout, stderr
+
+        result = wait_thr.value
+      end
+
+      return if result.success?
+
+      raise "Remote connection exited with code #{result}"
+    end
+  end
+end

lib/remote_ruby/connection_adapter/local_stdin_adapter.rb

@@ -1,10 +1,7 @@
-require 'open3'
-
 module RemoteRuby
   # An adapter to expecute Ruby code on the local macine
   # inside a specified directory
-  class LocalStdinAdapter < ConnectionAdapter
-    include Open3
+  class LocalStdinAdapter < ::RemoteRuby::ExternalProcessAdapter
     attr_reader :working_dir
 
     def initialize(working_dir: '.')
@@ -15,18 +12,10 @@ def connection_name
       working_dir
     end
 
-    def open(code)
-      result = nil
-
-      popen3('ruby', chdir: working_dir) do |stdin, stdout, stderr, wait_thr|
-        stdin.write(code)
-        stdin.close
-        yield stdout, stderr
-        result = wait_thr.value
-      end
+    private
 
-      return if result.success?
-      raise "Remote connection exited with code #{result}"
+    def command
+      "cd \"#{working_dir}\" && ruby"
     end
   end
 end

lib/remote_ruby/connection_adapter/ssh_stdin_adapter.rb

@@ -1,10 +1,6 @@
-require 'open3'
-
 module RemoteRuby
   # An adapter to execute Ruby code on the remote server via SSH
-  class SSHStdinAdapter < ConnectionAdapter
-    include Open3
-
+  class SSHStdinAdapter < ExternalProcessAdapter
     attr_reader :server, :working_dir, :user, :key_file
 
     def initialize(server:, working_dir: '~', user: nil, key_file: nil)
@@ -18,23 +14,6 @@ def connection_name
       "#{server}:#{working_dir}"
     end
 
-    def open(code)
-      result = nil
-
-      popen3(command) do |stdin, stdout, stderr, wait_thr|
-        stdin.write(code)
-        stdin.close
-
-        yield stdout, stderr
-
-        result = wait_thr.value
-      end
-
-      return if result.success?
-
-      raise "Remote connection exited with code #{result}"
-    end
-
     private
 
     def command