Merge pull request #258 from deivid-rodriguez/more_friendly_errors

More friendly errors

.rubocop_todo.yml

@@ -1,12 +1,12 @@
 # This configuration was generated by
 # `rubocop --auto-gen-config`
-# on 2016-05-10 10:05:38 +0200 using RuboCop version 0.39.0.
+# on 2016-05-14 08:08:13 +0200 using RuboCop version 0.40.0.
 # The point is for the user to remove these configuration records
 # one by one as the offenses are removed from the code base.
 # Note that changes in the inspected code, or installation of new
 # versions of RuboCop, may require this file to be generated again.
 
-# Offense count: 18
+# Offense count: 17
 Metrics/AbcSize:
   Max: 28
 
@@ -19,7 +19,7 @@ Metrics/ClassLength:
 Metrics/CyclomaticComplexity:
   Max: 10
 
-# Offense count: 59
+# Offense count: 58
 # Configuration parameters: CountComments.
 Metrics/MethodLength:
   Max: 39

CHANGELOG.md

@@ -2,6 +2,12 @@
 
 ## Master (Unreleased)
 
+### Fixed
+
+* Unfriendly output in byebug's executable when no script specified (#256).
+* Unfriendly output in byebug's executable when script doesn't exist.
+* Unfriendly output in byebug's executable when script has invalid code.
+
 ## 9.0.2 - 2016-05-15
 
 ### Fixed

lib/byebug/runner.rb

@@ -13,21 +13,6 @@ module Byebug
   class Runner
     include Helpers::ParseHelper
 
-    #
-    # Error class signaling absence of a script to debug.
-    #
-    class NoScript < StandardError; end
-
-    #
-    # Error class signaling a non existent script to debug.
-    #
-    class NonExistentScript < StandardError; end
-
-    #
-    # Error class signaling a script with invalid Ruby syntax.
-    #
-    class InvalidScript < StandardError; end
-
     #
     # Special working modes that don't actually start the debugger.
     #
@@ -63,7 +48,7 @@ def initialize(stop = true, quit = true)
     def help=(text)
       @help ||= text
 
-      interface.puts("\n#{text}\n")
+      interface.puts("#{text}\n")
     end
 
     def version=(number)
@@ -74,6 +59,8 @@ def version=(number)
 
     def remote=(host_and_port)
       @remote ||= Byebug.parse_host_and_port(host_and_port)
+
+      Byebug.start_client(*@remote)
     end
 
     def init_script
@@ -97,18 +84,11 @@ def banner
     # Starts byebug to debug a program.
     #
     def run
-      prepare_options.order!($ARGV)
-      return if version || help
-
-      if remote
-        Byebug.start_client(*remote)
-        return
-      end
+      option_parser.order!($ARGV)
+      return if non_script_option? || error_in_script?
 
       Byebug.run_init_script if init_script
 
-      setup_cmd_line_args
-
       loop do
         debug_program
 
@@ -127,36 +107,70 @@ def interface
     #
     # Processes options passed from the command line.
     #
-    def prepare_options
-      OptionParser.new(banner, 25) do |opts|
+    def option_parser
+      @option_parser ||= OptionParser.new(banner, 25) do |opts|
         opts.banner = banner
 
         OptionSetter.new(self, opts).setup
       end
     end
 
+    #
+    # An option that doesn't need a script specified was given
+    #
+    def non_script_option?
+      version || help || remote
+    end
+
+    #
+    # There is an error with the specified script
+    #
+    def error_in_script?
+      no_script? || non_existing_script? || invalid_script?
+    end
+
+    #
+    # No script to debug specified
+    #
+    def no_script?
+      return false unless $ARGV.empty?
+
+      print_error('You must specify a program to debug')
+      true
+    end
+
     #
     # Extracts debugged program from command line args.
     #
-    def setup_cmd_line_args
+    def non_existing_script?
       Byebug.mode = :standalone
 
-      raise(NoScript, 'You must specify a program to debug...') if $ARGV.empty?
-
       program = which($ARGV.shift)
       program = which($ARGV.shift) if program == which('ruby')
-      raise(NonExistentScript, "The script doesn't exist") unless program
 
-      $PROGRAM_NAME = program
+      if program
+        $PROGRAM_NAME = program
+        false
+      else
+        print_error("The script doesn't exist")
+        true
+      end
+    end
+
+    #
+    # Checks the debugged script has correct syntax
+    #
+    def invalid_script?
+      return false if syntax_valid?(File.read($PROGRAM_NAME))
+
+      print_error('The script has incorrect syntax')
+      true
     end
 
     #
     # Debugs a script only if syntax checks okay.
     #
     def debug_program
-      ok = syntax_valid?(File.read($PROGRAM_NAME))
-      raise(InvalidScript, 'The script has incorrect syntax') unless ok
-
       error = Byebug.debug_load($PROGRAM_NAME, stop)
       puts "#{error}\n#{error.backtrace}" if error
     end
@@ -178,5 +192,13 @@ def which(cmd)
 
       nil
     end
+
+    #
+    # Prints an error message and a help string
+    #
+    def print_error(msg)
+      interface.errmsg(msg)
+      interface.puts(option_parser.help)
+    end
   end
 end

test/runner_test.rb

@@ -47,13 +47,17 @@ def test_run_with_remote_option_with_host_and_port_specification
 
     def test_run_without_a_script_to_debug
       with_command_line('bin/byebug') do
-        assert_raises(Runner::NoScript) { runner.run }
+        runner.run
+
+        check_error_includes 'You must specify a program to debug'
       end
     end
 
     def test_run_with_an_nonexistent_script
       with_command_line('bin/byebug', 'non_existent_script.rb') do
-        assert_raises(Runner::NonExistentScript) { runner.run }
+        runner.run
+
+        check_error_includes "The script doesn't exist"
       end
     end
 
@@ -62,7 +66,9 @@ def test_run_with_an_invalid_script
       example_file.close
 
       with_command_line('bin/byebug', example_path) do
-        assert_raises(Runner::InvalidScript) { runner.run }
+        runner.run
+
+        check_error_includes 'The script has incorrect syntax'
       end
     end