Introduced clear_stdout_lines and clear_stderr_lines on Command

This commit removes duplication in the SimpleText and Pretty formatters by better encapsulating the logic to split and clear stdout/stderr buffers on the Command object.

lib/sshkit/command.rb

@@ -83,6 +83,14 @@ def failure?
     end
     alias :failed? :failure?
 
+    def clear_stdout_lines
+      @stdout.lines.tap { @stdout.clear }
+    end
+
+    def clear_stderr_lines
+      @stderr.lines.tap { @stderr.clear }
+    end
+
     def exit_status=(new_exit_status)
       @finished_at = Time.now
       @exit_status = new_exit_status

lib/sshkit/formatters/pretty.rb

@@ -28,22 +28,16 @@ def write_command(command)
         end
 
         if SSHKit.config.output_verbosity == Logger::DEBUG
-          unless command.stdout.empty?
-            command.stdout.lines.each do |line|
-              original_output << "%6s %s" % [level(Logger::DEBUG),
-                                             uuid(command) + c.green("\t" + line)]
-              original_output << "\n" unless line[-1] == "\n"
-            end
-            command.stdout = ''
+          command.clear_stdout_lines.each do |line|
+            original_output << "%6s %s" % [level(Logger::DEBUG),
+                                           uuid(command) + c.green("\t" + line)]
+            original_output << "\n" unless line[-1] == "\n"
           end
 
-          unless command.stderr.empty?
-            command.stderr.lines.each do |line|
-              original_output << "%6s %s" % [level(Logger::DEBUG),
-                                             uuid(command) + c.red("\t" + line)]
-              original_output << "\n" unless line[-1] == "\n"
-            end
-            command.stderr = ''
+          command.clear_stderr_lines.each do |line|
+            original_output << "%6s %s" % [level(Logger::DEBUG),
+                                           uuid(command) + c.red("\t" + line)]
+            original_output << "\n" unless line[-1] == "\n"
           end
         end
 

lib/sshkit/formatters/simple_text.rb

@@ -27,20 +27,14 @@ def write_command(command)
         end
 
         if SSHKit.config.output_verbosity == Logger::DEBUG
-          unless command.stdout.empty?
-            command.stdout.lines.each do |line|
-              original_output << "\t" + line
-              original_output << "\n" unless line[-1] == "\n"
-            end
-            command.stdout = ''
+          command.clear_stdout_lines.each do |line|
+            original_output << "\t" + line
+            original_output << "\n" unless line[-1] == "\n"
           end
 
-          unless command.stderr.empty?
-            command.stderr.lines.each do |line|
-              original_output << "\t" + line
-              original_output << "\n" unless line[-1] == "\n"
-            end
-            command.stderr = ''
+          command.clear_stderr_lines.each do |line|
+            original_output << "\t" + line
+            original_output << "\n" unless line[-1] == "\n"
           end
         end
 

test/unit/test_command.rb

@@ -199,5 +199,11 @@ def test_command_raises_command_failed_error_when_non_zero_exit
       assert_equal "whoami exit status: 1\nwhoami stdout: Nothing written\nwhoami stderr: Nothing written\n", error.message
     end
 
+    def test_clear_lines_methods_return_empty_array_when_blank
+      command = Command.new(:some_command)
+      assert_equal [], command.clear_stdout_lines
+      assert_equal [], command.clear_stderr_lines
+    end
+
   end
 end