Remove the compulsary "" argument to alias_command

examples/example_command_override.rb

@@ -14,7 +14,7 @@ class MyCommands < Pry::CommandBase
   import_from Pry::Commands, "status"
 
   # analogy to Ruby's native alias_method idiom for decorating a method
-  alias_command "old_status", "status", ""
+  alias_command "old_status", "status"
 
   # Invoke one command from within another using `run`
   command "status", "Modified status."  do |x|

lib/pry/command_set.rb

@@ -168,10 +168,10 @@ class Pry
     # @param [String] new_name New name of the command.
     # @param [String] old_name Old name of the command.
     # @param [String, nil] desc New description of the command.
-    def alias_command(new_name, old_name, desc = nil)
+    def alias_command(new_name, old_name, desc="")
       commands[new_name] = commands[old_name].dup
       commands[new_name].name = new_name
-      commands[new_name].description = desc if desc
+      commands[new_name].description = desc
     end
 
     # Runs a command.

lib/pry/default_commands/context.rb

@@ -91,7 +91,7 @@ class Pry
         throw(:breakout, target.eval(arg_string))
       end
 
-      alias_command "!!@", "exit-all", ""
+      alias_command "!!@", "exit-all"
 
       command "exit", "Pop the current binding and return to the one immediately prior. Note this does NOT exit the program. Aliases: quit", :keep_retval => true do
         if _pry_.binding_stack.one?
@@ -111,15 +111,15 @@ class Pry
         end
       end
 
-      alias_command "quit", "exit", ""
+      alias_command "quit", "exit"
 
       command "exit-program", "End the current program. Aliases: quit-program, !!!" do
         Pry.save_history if Pry.config.history.should_save
         Kernel.exit target.eval(arg_string).to_i
       end
 
-      alias_command "quit-program", "exit-program", ""
+      alias_command "quit-program", "exit-program"
-      alias_command "!!!", "exit-program", ""
+      alias_command "!!!", "exit-program"
 
       command "!pry", "Start a Pry session on current self; this even works mid multi-line expression." do
         target.pry

lib/pry/default_commands/documentation.rb

@@ -52,7 +52,7 @@ class Pry
         end
       end
 
-      alias_command "?", "show-doc", ""
+      alias_command "?", "show-doc"
 
       command "stat", "View method information and set _file_ and _dir_ locals. Type `stat --help` for more info." do |*args|
         target = target()

lib/pry/default_commands/input.rb

@@ -54,7 +54,7 @@ class Pry
         run "show-input"
       end
 
-      alias_command(/%.?(-?\d+)?(?:\.\.(-?\d+))?/, /amend-line(?: (-?\d+)(?:\.\.(-?\d+))?)?/, "")
+      alias_command(/%.?(-?\d+)?(?:\.\.(-?\d+))?/, /amend-line(?: (-?\d+)(?:\.\.(-?\d+))?)?/)
 
       command "play", "Play back a string variable or a method or a file as input. Type `play --help` for more information." do |*args|
         opts = Slop.parse!(args) do |opt|
@@ -270,7 +270,7 @@ class Pry
         end
       end
 
-      alias_command "history", "hist", ""
+      alias_command "history", "hist"
 
       helpers do
         def one_index_number(line_number)

lib/pry/default_commands/introspection.rb

@@ -60,8 +60,8 @@ class Pry
         end
       end
 
-      alias_command "show-source", "show-method", ""
+      alias_command "show-source", "show-method"
-      alias_command "$", "show-method", ""
+      alias_command "$", "show-method"
 
       command "show-command", "Show the source for CMD. Type `show-command --help` for more info." do |*args|
         target = target()

lib/pry/default_commands/shell.rb

@@ -29,7 +29,7 @@ class Pry
         end
       end
 
-      alias_command "file-mode", "shell-mode", ""
+      alias_command "file-mode", "shell-mode"
 
       command "cat", "Show output of file FILE. Type `cat --help` for more information." do |*args|
         start_line = 0

test/test_command_set.rb

@@ -99,7 +99,7 @@ describe Pry::CommandSet do
 
     @set.alias_command 'bar', 'foo'
     @set.commands['bar'].name.should == 'bar'
-    @set.commands['bar'].description.should == 'stuff'
+    @set.commands['bar'].description.should == ''
 
     @set.run_command nil, 'bar'
     run.should == true