Add test for unrecognized command

lib/youplot.rb

@@ -8,8 +8,10 @@ require 'youplot/command'
 module YouPlot
   class << self
     attr_accessor :run_as_executable
+
     def run_as_executable?
       @run_as_executable
     end
   end
+  @run_as_executable = false
 end

lib/youplot/command/parser.rb

@@ -7,6 +7,8 @@ require_relative 'plot_params'
 module YouPlot
   class Command
     class Parser
+      class Error < StandardError; end
+
       attr_reader :command, :options, :params,
                   :main_parser, :sub_parser
 
@@ -193,7 +195,7 @@ module YouPlot
         when nil
           warn main_parser.banner
           warn "\n"
-          exit 1
+          exit 1 if YouPlot.run_as_executable?
 
         when :barplot, :bar
           sub_parser_add_symbol
@@ -263,8 +265,13 @@ module YouPlot
           end
 
         else
-          warn "uplot: unrecognized command '#{command}'"
+          error_message = "uplot: unrecognized command '#{command}'"
-          exit 1
+          if YouPlot.run_as_executable?
+            warn error_message
+            exit 1
+          else
+            raise Error, error_message
+          end
         end
       end
 
@@ -273,16 +280,16 @@ module YouPlot
           create_main_parser.order!(argv)
         rescue OptionParser::ParseError => e
           warn "uplot: #{e.message}"
-          exit 1
+          exit 1 if YouPlot.run_as_executable?
         end
 
         @command = argv.shift&.to_sym
 
         begin
-          create_sub_parser.parse!(argv)
+          create_sub_parser&.parse!(argv)
         rescue OptionParser::ParseError => e
           warn "uplot: #{e.message}"
-          exit 1
+          exit 1 if YouPlot.run_as_executable?
         end
       end
     end

test/youplot/command_test.rb

@@ -138,4 +138,12 @@ class YouPlotCommandTest < Test::Unit::TestCase
     assert_equal '', @stderr_file.read
     assert_equal fixture('colors.txt'), @stdout_file.read
   end
+
+  test :unrecognized_command do
+    assert_raise(YouPlot::Command::Parser::Error) do
+      YouPlot::Command.new(['abracadabra', '--hadley', '--wickham']).run
+    end
+    assert_equal '', @stderr_file.read
+    assert_equal '', @stdout_file.read
+  end
 end