Remove init option to Byebug.start

This option was used to enable/disable saving information about program
path and arguments to make restarts possible. This feature has been
removed and this information is always saved now. This also fixes some
order dependent failures in the `restart` command tests.

CHANGELOG.md

@@ -15,6 +15,8 @@ behaves like shell's `history` command.
 [50e6ad8](https://github.com/deivid-rodriguez/byebug/commit/50e6ad8)
  * Changes in `finish` semantics and in the C extension API: see
 [61f9b4d](https://github.com/deivid-rodriguez/byebug/commit/61f9b4d)
+ * The `init` option for Byebug.start has been removed. Information to make the
+`restart` command work is always saved now.
 
 - Features
  * Allow disabling post_mortem mode

lib/byebug.rb

@@ -14,16 +14,20 @@ module Byebug
   IGNORED_FILES = Dir.glob(File.expand_path('../**/*.rb', __FILE__))
 
   # Default options to Byebug.start
-  DEFAULT_START_SETTINGS = {
-    init:        true,  # Set $0 and save ARGV?
-    post_mortem: false, # post-mortem debugging on uncaught exception?
-    tracing:     nil,   # Byebug.tracing? value. true/false resets
-    save_history: true  # Save history of byebug commands?
-  } unless defined?(DEFAULT_START_SETTINGS)
+  unless defined?(DEFAULT_START_SETTINGS)
+    DEFAULT_START_SETTINGS = { post_mortem: false,
+                               tracing: false,
+                               save_history: true }
+  end
 
   # Configuration file used for startup commands. Default value is .byebugrc
   INITFILE = '.byebugrc' unless defined?(INITFILE)
 
+  # Original ARGV, command line and initial directory to make restarts possible
+  ARGV = ARGV.clone unless defined?(ARGV)
+  PROG_SCRIPT = $0 unless defined?(PROG_SCRIPT)
+  INITIAL_DIR = Dir.pwd unless defined?(INITIAL_DIR)
+
   class << self
 
     # processor modules provide +handler+ object
@@ -99,26 +103,23 @@ def interface=(value)
     # many times as you called Byebug.start method.</i>
     #
     # +options+ is a hash used to set various debugging options.
-    #   :init        - true if you want to save ARGV and some other variables to
-    #                  make a byebug restart possible. Only the first time :init
-    #                  is set to true the values will get set. Since ARGV is
-    #                  saved, you should make sure it hasn't been changed before
-    #                  the (first) call.
-    #   :post_mortem - true if you want to enter post-mortem debugging on an
-    #                  uncaught exception. Once post-mortem debugging is set, it
-    #                  can't be unset.
+    #   :post_mortem  - true if you want to enter post-mortem debugging on an
+    #                   uncaught exception, false otherwise. Default: false.
+    #   :tracing      - true if line tracing should be enabled, false otherwise.
+    #                   Default: false.
+    #   :save_history - true if byebug's command history should be saved to a
+    #                   file on program termination so that it can be reloaded
+    #                   later.
     #
     def start(options={}, &block)
       options = Byebug::DEFAULT_START_SETTINGS.merge(options)
-      if options[:init]
-        Byebug.const_set('ARGV', ARGV.clone) unless defined? Byebug::ARGV
-        Byebug.const_set('PROG_SCRIPT', $0) unless defined? Byebug::PROG_SCRIPT
-        Byebug.const_set('INITIAL_DIR', Dir.pwd) unless defined? Byebug::INITIAL_DIR
-      end
-      Byebug.tracing = options[:tracing] unless options[:tracing].nil?
+      Byebug.tracing = options[:tracing]
+
       retval = Byebug._start(&block)
+
       post_mortem if options[:post_mortem]
       at_exit { Byebug::History.save } if options[:save_history]
+
       return retval
     end
 

test/restart_test.rb

@@ -60,47 +60,26 @@ class TestRestart < TestDsl::TestCase
     describe 'no script specified' do
       temporary_change_const Byebug, 'PROG_SCRIPT', :__undefined__
 
-      describe 'and no $0 used' do
-        temporary_change_const Byebug, 'DEFAULT_START_SETTINGS',
-          { init: false, post_mortem: false, tracing: nil }
-
-        it 'must not restart and show error messages instead' do
-          must_restart.never
-          debug_file 'restart'
-          check_output_includes 'Don\'t know name of debugged program',
-                                interface.error_queue
-        end
-      end
-
-      describe 'but initialized from $0' do
-        it 'must use prog_script from $0' do
-          old_prog_name = $0
-          $0 = 'prog-0'
-          debug_file 'restart'
-          check_output_includes 'Ruby program prog-0 doesn\'t exist',
+      it 'must not restart and show error messages instead' do
+        must_restart.never
+        debug_file 'restart'
+        check_output_includes 'Don\'t know name of debugged program',
                                 interface.error_queue
-          $0 = old_prog_name
-        end
       end
     end
 
     describe 'no script at the specified path' do
       temporary_change_const Byebug, 'PROG_SCRIPT', 'blabla'
 
-      describe 'and no restart params set' do
-        temporary_change_const Byebug, 'DEFAULT_START_SETTINGS',
-          init: false, post_mortem: false, tracing: nil
-
-        it 'must not restart' do
-          must_restart.never
-          debug_file 'restart'
-        end
+      it 'must not restart' do
+        must_restart.never
+        debug_file 'restart'
+      end
 
-        it 'must show an error message' do
-          debug_file 'restart'
-          check_output_includes 'Ruby program blabla doesn\'t exist',
-                                interface.error_queue
-        end
+      it 'must show an error message' do
+        debug_file 'restart'
+        check_output_includes 'Ruby program blabla doesn\'t exist',
+                              interface.error_queue
       end
     end