use status 0 for kernel.exit

Author: ignacio-chiazzo

lib/irb.rb

@@ -886,11 +886,11 @@ def IRB.start(ap_path = nil)
 
   # Quits irb
   def IRB.irb_exit(*)
-    throw :IRB_EXIT
+    throw :IRB_EXIT, false
   end
 
   def IRB.irb_exit!(*)
-    throw :IRB_EXIT!
+    throw :IRB_EXIT, true
   end
 
   # Aborts then interrupts irb.
@@ -986,19 +986,16 @@ def run(conf = IRB.conf)
       begin
         @forced_exit = false
 
-        catch(:IRB_EXIT) do
-          catch(:IRB_EXIT!) do
-            eval_input
-          end
-          @forced_exit = true
+        @forced_exit = catch(:IRB_EXIT) do
+          eval_input
         end
       ensure
         trap("SIGINT", prev_trap)
         conf[:AT_EXIT].each{|hook| hook.call}
 
         if @forced_exit
           context.io.save_history if supports_history_saving
-          Kernel.exit!
+          Kernel.exit!(0)
         else
           context.io.save_history if save_history
         end

lib/irb/cmd/exit_forced_action.rb

@@ -13,7 +13,7 @@ class ExitForcedAction < Nop
       def execute(*)
         IRB.irb_exit!
       rescue UncaughtThrowError
-        Kernel.exit
+        Kernel.exit(0)
       end
     end
   end

test/irb/test_debug_cmd.rb

@@ -257,12 +257,12 @@ def test_exit
 
     def test_forced_exit
       write_ruby <<~'ruby'
-        puts "first line"
+        puts "First line"
+        puts "Second line"
         binding.irb
-        puts "second line"
-        binding.irb
-        puts "third"
+        puts "Third line"
         binding.irb
+        puts "Fourth line"
       ruby
 
       output = run_ruby_file do
@@ -271,10 +271,12 @@ def test_forced_exit
         type "exit!"
       end
 
+      assert_match(/First line\r\n/, output)
+      assert_match(/Second line\r\n/, output)
       assert_match(/irb\(main\):001> 123/, output)
       assert_match(/irb\(main\):002> 456/, output)
-      assert_match(/irb\(main\):003> exit!/, output)
-      output.end_with?("003> exit!")
+      refute_match(/Third line\r\n/, output)
+      refute_match(/Fourth line\r\n/, output)
     end
 
     def test_quit