[ruby/irb] Add commands to start and use the debugger

(https://github.com/ruby/irb/pull/449)

* Seamlessly integrate a few debug commands

* Improve the break command support

* Utilize skip_src option if available

* Add step and delete commands

* Write end-to-end tests for each debugger command

* Add documentation

* Add backtrace, info, catch commands

https://github.com/ruby/irb/commit/976100c1c2

1 files changed, 11 insertions, 5 deletions

diff --git a/lib/irb/context.rb b/lib/irb/context.rb
index c5d98772b8..91fbb2fcf1 100644
--- a/lib/irb/context.rb
+++ b/lib/irb/context.rb
@@ -486,9 +486,9 @@ module IRB
         @workspace.local_variable_set(:_, exception)
       end
 
-      # Transform a non-identifier alias (ex: @, $)
+      # Transform a non-identifier alias (@, $) or keywords (next, break)
       command, args = line.split(/\s/, 2)
-      if original = symbol_alias(command)
+      if original = command_aliases[command.to_sym]
         line = line.gsub(/\A#{Regexp.escape(command)}/, original.to_s)
         command = original
       end
@@ -545,10 +545,16 @@ module IRB
       workspace.binding.local_variables
     end
 
-    # Return a command name if it's aliased from the argument and it's not an identifier.
-    def symbol_alias(command)
+    # Return true if it's aliased from the argument and it's not an identifier.
+    def symbol_alias?(command)
       return nil if command.match?(/\A\w+\z/)
-      command_aliases[command.to_sym]
+      command_aliases.key?(command.to_sym)
+    end
+
+    # Return true if the command supports transforming args
+    def transform_args?(command)
+      command = command_aliases.fetch(command.to_sym, command)
+      ExtendCommandBundle.load_command(command)&.respond_to?(:transform_args)
     end
   end
 end