added Pry.config.extra_sticky_locals config option

* Pry.config.extra_sticky_locals[:random] = proc { rand(10) }
* alternatively, Pry.start binding, :extra_sticky_locals => { :random => proc { rand(10) } }
* updated tests

lib/pry/config.rb

@@ -171,6 +171,12 @@ class Pry
     #   Pry.config.gist.inspecter = proc &:inspect
     # @return [OpenStruct]
     attr_accessor :gist
+
+    # @return [Hash] Additional sticky locals (to the standard ones) to use in Pry sessions.
+    # @example Inject `random_number` sticky local into Pry session
+    #   Pry.config.extra_sticky_locals = { :random_number => proc {
+    #   rand(10) } }
+    attr_accessor :extra_sticky_locals
   end
 end
 

lib/pry/default_commands/editing.rb

@@ -343,7 +343,7 @@ class Pry
             self.content << File.read(File.expand_path(file))
           end
           opt.on :l, :lines, "Only play a subset of lines.", :optional => true, :as => Range, :default => 1..-1
-          opt.on :i, :in, "Play entries from Pry's input expression history. Takes an index or range.", :optional => true,
+          opt.on :i, :in, "Play entries from Pry's input expression history. Takes an index or range. Note this can only replay pure Ruby code, not Pry commands.", :optional => true,
           :as => Range, :default => -5..-1 do |range|
             input_expressions = _pry_.input_array[range] || []
             Array(input_expressions).each { |v| self.content << v }

lib/pry/pry_class.rb

@@ -50,7 +50,7 @@ class Pry
     def_delegators :@plugin_manager, :plugins, :load_plugins, :locate_plugins
 
     delegate_accessors :@config, :input, :output, :commands, :prompt, :print, :exception_handler,
-      :hooks, :color, :pager, :editor, :memory_size, :input_stack
+      :hooks, :color, :pager, :editor, :memory_size, :input_stack, :extra_sticky_locals
   end
 
   # Load the rc files given in the `Pry::RC_FILES` array.
@@ -261,6 +261,8 @@ class Pry
 
     config.memory_size = 100
 
+    config.extra_sticky_locals = {}
+
     config.ls ||= OpenStruct.new({
       :heading_color            => :default,
 

lib/pry/pry_instance.rb

@@ -24,6 +24,8 @@ class Pry
 
   attr_accessor :backtrace
 
+  attr_accessor :extra_sticky_locals
+
   # Special treatment for hooks as we want to alert people of the
   # changed API
   attr_reader :hooks
@@ -65,7 +67,7 @@ class Pry
     attributes = [
                    :input, :output, :commands, :print,
                    :exception_handler, :hooks, :custom_completions,
-                   :prompt, :memory_size, :input_stack
+                   :prompt, :memory_size, :input_stack, :extra_sticky_locals
                  ]
 
     attributes.each do |attribute|
@@ -155,7 +157,7 @@ class Pry
       :_file_ => proc { last_file },
       :_dir_  => proc { last_dir },
       :_      => proc { last_result }
-    }
+    }.merge(extra_sticky_locals)
   end
 
   # Initialize the repl session.

test/test_sticky_locals.rb

@@ -32,7 +32,87 @@ describe "Sticky locals (_file_ and friends)" do
     Pry.commands.delete "file-and-dir-test"
   end
 
-  describe "User defined sticky locals, Pry#add_sticky_local()" do
+  describe "User defined sticky locals" do
+    describe "setting as Pry.config option" do
+      it 'should define a new sticky local for the session (normal value)' do
+        Pry.config.extra_sticky_locals[:test_local] = :john
+
+        o = Object.new
+        redirect_pry_io(InputTester.new("@value = test_local",
+                                        "exit-all")) do
+          Pry.start(o)
+        end
+
+        o.instance_variable_get(:@value).should == :john
+        Pry.config.extra_sticky_locals = {}
+      end
+
+      it 'should define a new sticky local for the session (proc)' do
+        Pry.config.extra_sticky_locals[:test_local] = proc { :john }
+
+        o = Object.new
+        redirect_pry_io(InputTester.new("@value = test_local",
+                                        "exit-all")) do
+          Pry.start(o)
+        end
+
+        o.instance_variable_get(:@value).should == :john
+        Pry.config.extra_sticky_locals = {}
+      end
+
+    end
+
+    describe "passing in as hash option when creating pry instance" do
+      it 'should define a new sticky local for the session (normal value)' do
+        o = Object.new
+        redirect_pry_io(InputTester.new("@value = test_local",
+                                        "exit-all")) do
+          Pry.start(o, :extra_sticky_locals => { :test_local => :john } )
+        end
+
+        o.instance_variable_get(:@value).should == :john
+      end
+
+      it 'should define multiple sticky locals' do
+        o = Object.new
+        redirect_pry_io(InputTester.new("@value1 = test_local1",
+                                        "@value2 = test_local2",
+                                        "exit-all")) do
+          Pry.start(o, :extra_sticky_locals => { :test_local1 => :john ,
+                      :test_local2 => :carl} )
+        end
+
+        o.instance_variable_get(:@value1).should == :john
+        o.instance_variable_get(:@value2).should == :carl
+      end
+
+
+      it 'should define a new sticky local for the session (as Proc)' do
+        o = Object.new
+        redirect_pry_io(InputTester.new("@value = test_local",
+                                        "exit-all")) do
+          Pry.start(o, :extra_sticky_locals => { :test_local => proc { :john }} )
+        end
+
+        o.instance_variable_get(:@value).should == :john
+      end
+    end
+
+    describe "hash option value should override config value" do
+      it 'should define a new sticky local for the session (normal value)' do
+        Pry.config.extra_sticky_locals[:test_local] = :john
+
+        o = Object.new
+        redirect_pry_io(InputTester.new("@value = test_local",
+                                        "exit-all")) do
+          Pry.start(o, :extra_sticky_locals => { :test_local => :carl })
+        end
+
+        o.instance_variable_get(:@value).should == :carl
+        Pry.config.extra_sticky_locals = {}
+      end
+    end
+
     it 'should create a new sticky local' do
       o = Object.new
       pi = Pry.new