supercharged Pry.commands.alias_command method

* Now accepts arbitrary command code for alias, e.g
  alias_command "lM", "ls -M"
* Adds all aliases to the "Aliases" group in `help`

lib/pry/command.rb

@@ -42,7 +42,6 @@ class Pry
       end
     end
 
-
     # Make those properties accessible to instances
     def name; self.class.name; end
     def description; self.class.description; end
@@ -145,7 +144,11 @@ class Pry
           when /pryrc/
             "~/.pryrc"
           else
-            "(other)"
+            if options[:alias]
+              "Aliases"
+            else
+              "(other)"
+            end
           end
         )
       end

lib/pry/command_set.rb

@@ -200,14 +200,30 @@ class Pry
     protected :find_command_by_name_or_listing
 
     # Aliases a command
-    # @param [String] new_name New name of the command.
-    # @param [String] old_name Old name of the command.
+    # Note that if `desc` parameter is `nil` then the default
+    # description is used.
+    # @param [String, Regex] name The name of the alias (can be a regex).
+    # @param [String] action The action to be performed (typically
+    #   another command).
     # @param [String, nil] desc New description of the command.
-    def alias_command(new_name, old_name, desc="")
-      orig_command = find_command_by_name_or_listing(old_name)
-      commands[new_name] = orig_command.dup
-      commands[new_name].name = new_name
-      commands[new_name].description = desc
+    # @param [Hash] options The optional configuration parameters,
+    #   accepts the same as the `command` method, but also allows the
+    #   command description to be passed this way too.
+    # @example Creating an alias for `ls -M`
+    #   Pry.config.commands.alias_command "lM", "ls -M"
+    def alias_command(name, action, desc="Alias for `#{action}`", options={})
+      options = {
+        :alias => true
+      }.merge!(options)
+
+      # ensure default description is used if desc is nil
+      desc = "Alias for `#{action}`" if !desc
+
+      create_command name, desc, options do
+        define_method(:process) do
+          run action, *args
+        end
+      end
     end
 
     # Rename a command. Accepts either actual name or listing name for

test/test_command_integration.rb

@@ -1,5 +1,117 @@
 require 'helper'
 describe "commands" do
+
+  describe "alias_command" do
+    it 'should make an aliasd command behave like its original' do
+      set = Pry::CommandSet.new do
+        command "test-command" do
+          output.puts "testing 1, 2, 3"
+        end
+        alias_command "test-alias", "test-command"
+      end
+      redirect_pry_io(InputTester.new("test-alias"), out1 = StringIO.new) do
+        Pry.start self, :commands => set
+      end
+
+      redirect_pry_io(InputTester.new("test-command"), out2 = StringIO.new) do
+        Pry.start self, :commands => set
+      end
+
+      out1.string.should == out2.string
+    end
+
+    it 'should pass on arguments to original' do
+      set = Pry::CommandSet.new do
+        command "test-command" do |*args|
+          output.puts "testing #{args.join(' ')}"
+        end
+        alias_command "test-alias", "test-command"
+      end
+
+      redirect_pry_io(InputTester.new("test-command hello baby duck"), out1 = StringIO.new) do
+        Pry.start self, :commands => set
+      end
+
+      out1.string.should =~ /hello baby duck/
+
+      redirect_pry_io(InputTester.new("test-alias hello baby duck"), out2 = StringIO.new) do
+        Pry.start self, :commands => set
+      end
+
+      out2.string.should == out1.string
+    end
+
+    it 'should pass option arguments to original' do
+      set = Pry::CommandSet.new do
+        import Pry::Commands
+        alias_command "test-alias", "ls"
+      end
+
+      obj = Class.new { @x = 10 }
+      redirect_pry_io(InputTester.new("ls -i"), out1 = StringIO.new) do
+        Pry.start obj, :commands => set
+      end
+
+      out1.string.should =~ /@x/
+
+      redirect_pry_io(InputTester.new("test-alias -i"), out2 = StringIO.new) do
+        Pry.start obj, :commands => set
+      end
+
+      out2.string.should == out1.string
+    end
+
+    it 'should pass option arguments to original with additional parameters' do
+      set = Pry::CommandSet.new do
+        import Pry::Commands
+        alias_command "test-alias", "ls -M"
+      end
+
+      obj = Class.new { @x = Class.new { define_method(:plymouth) {} } }
+      redirect_pry_io(InputTester.new("ls -M @x"), out1 = StringIO.new) do
+        Pry.start obj, :commands => set
+      end
+
+      out1.string.should =~ /plymouth/
+
+      redirect_pry_io(InputTester.new("test-alias @x"), out2 = StringIO.new) do
+        Pry.start obj, :commands => set
+      end
+
+      out2.string.should == out1.string
+    end
+
+    it 'should be able to alias a regex command' do
+      set = Pry::CommandSet.new do
+        command /du.k/ do
+          output.puts "ducky"
+        end
+        alias_command "test-alias", "duck"
+      end
+
+      redirect_pry_io(InputTester.new("test-alias"), out1 = StringIO.new) do
+        Pry.start self, :commands => set
+      end
+
+      out1.string.should =~ /ducky/
+    end
+
+    it 'should be able to make the alias a regex' do
+      set = Pry::CommandSet.new do
+        command /du.k/ do
+          output.puts "ducky"
+        end
+        alias_command /test-ali.s/, "duck"
+      end
+
+      redirect_pry_io(InputTester.new("test-alias"), out1 = StringIO.new) do
+        Pry.start self, :commands => set
+      end
+
+      out1.string.should =~ /ducky/
+    end
+  end
+
   it 'should interpolate ruby code into commands' do
     klass = Pry::CommandSet.new do
       command "hello", "", :keep_retval => true do |arg|
@@ -299,14 +411,6 @@ str_output.string !~ /=>/
     klass.commands.include?("v").should == true
   end
 
-  it 'should alias a command with another command' do
-    klass = Pry::CommandSet.new do
-      import Pry::DefaultCommands::Help
-      alias_command "help2", "help"
-    end
-    klass.commands["help2"].block.should == klass.commands["help"].block
-  end
-
   it 'should change description of a command using desc' do
     klass = Pry::CommandSet.new do; import Pry::DefaultCommands::Help; end
     orig = klass.commands["help"].description

test/test_command_set.rb

@@ -121,28 +121,58 @@ describe Pry::CommandSet do
     @set.commands['foo'].description.should == 'some stuff'
   end
 
-  it 'should be able to alias method' do
-    run = false
-    @set.command('foo', 'stuff') { run = true }
+  describe "aliases" do
+    it 'should be able to alias command' do
+      run = false
+      @set.command('foo', 'stuff') { run = true }
 
-    @set.alias_command 'bar', 'foo'
-    @set.commands['bar'].name.should == 'bar'
-    @set.commands['bar'].description.should == ''
+      @set.alias_command 'bar', 'foo'
+      @set.commands['bar'].name.should == 'bar'
+      @set.commands['bar'].description.should == 'Alias for `foo`'
 
-    @set.run_command @ctx, 'bar'
-    run.should == true
-  end
+      @set.run_command @ctx, 'bar'
+      run.should == true
+    end
 
-  it "should be able to alias a method by the command's listing name" do
-    run = false
-    @set.command(/^foo1/, 'stuff', :listing => 'foo') { run = true }
+    it 'should be able to specify alias\'s description when aliasing' do
+      run = false
+      @set.command('foo', 'stuff') { run = true }
 
-    @set.alias_command 'bar', 'foo'
-    @set.commands['bar'].name.should == 'bar'
-    @set.commands['bar'].description.should == ''
+      @set.alias_command 'bar', 'foo', "tobina"
+      @set.commands['bar'].name.should == 'bar'
+      @set.commands['bar'].description.should == "tobina"
 
-    @set.run_command @ctx, 'bar'
-    run.should == true
+      @set.run_command @ctx, 'bar'
+      run.should == true
+    end
+
+    it "should be able to alias a command by its invocation line" do
+      run = false
+      @set.command(/^foo1/, 'stuff', :listing => 'foo') { run = true }
+
+      @set.alias_command 'bar', 'foo1'
+      @set.commands['bar'].name.should == 'bar'
+      @set.commands['bar'].description.should == 'Alias for `foo1`'
+
+      @set.run_command @ctx, 'bar'
+      run.should == true
+    end
+
+    it "should be able to specify options when creating alias" do
+      run = false
+      @set.command(/^foo1/, 'stuff', :listing => 'foo') { run = true }
+
+      @set.alias_command /^b.r/, 'foo1', nil, :listing => "bar"
+      @set.commands[/^b.r/].options[:listing].should == "bar"
+    end
+
+    it "should set description to default if description parameter is nil" do
+      run = false
+      @set.command(/^foo1/, 'stuff', :listing => 'foo') { run = true }
+
+      @set.alias_command "bar", 'foo1', nil
+      @set.commands["bar"].description.should == "Alias for `foo1`"
+    end
   end
 
   it 'should be able to change the descriptions of commands' do