replace direct Readline interface with InputHistory

lib/pry.rb

@@ -130,6 +130,7 @@ end
 require "pry/version"
 require "pry/history_array"
 require "pry/helpers"
+require "pry/input_history"
 require "pry/command_set"
 require "pry/commands"
 require "pry/command_context"

lib/pry/default_commands/input.rb

@@ -97,7 +97,7 @@ e.g amend-line puts 'hello again'   # no line number modifies immediately preced
 
       command "hist", "Show and replay Readline history. Type `hist --help` for more info. Aliases: history" do |*args|
         # exclude the current command from history.
-        history = Readline::HISTORY.to_a[0..-2]
+        history = Pry.input_history.to_a[0..-2]
 
         opts = Slop.parse!(args) do |opt|
           opt.banner "Usage: hist [--replay START..END] [--clear] [--grep PATTERN] [--head N] [--tail N] [--help] [--save [START..END] file.txt]\n"
@@ -132,7 +132,7 @@ e.g amend-line puts 'hello again'   # no line number modifies immediately preced
                      :unless   => :grep do |limit|
 
             limit ||= 10
-            offset = history.size-limit
+            offset = history.size - limit
             offset = offset < 0 ? 0 : offset
 
             list  = history.last limit
@@ -170,7 +170,7 @@ e.g amend-line puts 'hello again'   # no line number modifies immediately preced
           opt.on "save", "Save history to a file. --save [start..end] output.txt. Pry commands are excluded from saved history.", true, :as => Range
 
           opt.on :c, :clear, 'Clear the history', :unless => :grep do
-            Readline::HISTORY.shift until Readline::HISTORY.empty?
+            Pry.input_history.clear
             output.puts 'History cleared.'
           end
 

lib/pry/input_history.rb

@@ -0,0 +1,44 @@
+class Pry
+  class InputHistory
+    def initialize
+      @history = []
+      @first_new_line = 0 # TODO: rename this
+    end
+
+    def load(filename)
+      File.foreach(filename) do |line|
+        Readline::HISTORY << line.chomp
+        @history << line.chomp
+      end
+      @first_new_line = @history.length
+    end
+
+    def save(filename)
+      history_to_save = @history[@first_new_line..-1]
+      File.open(filename, 'a') do |f|
+        history_to_save.each { |ln| f.puts ln }
+      end
+      @first_new_line = @history.length
+    end
+
+    def push(line)
+      line = line.to_s
+      unless line.empty? || (@history.last && line.strip == @history.last.strip)
+        Readline::HISTORY << line
+        @history << line
+      end
+      line
+    end
+    alias << push
+
+    def clear
+      Readline::HISTORY.shift until Readline::HISTORY.empty?
+      @history = []
+      @first_new_line = 0
+    end
+
+    def to_a
+      @history.dup
+    end
+  end
+end

lib/pry/pry_class.rb

@@ -38,6 +38,9 @@ class Pry
     # @return [OpenStruct] Return Pry's config object.
     attr_accessor :config
 
+    # @return [InputHistory] TODO: put something here
+    attr_accessor :input_history
+
     # @return [Boolean] Whether Pry was activated from the command line.
     attr_accessor :cli
 
@@ -123,33 +126,12 @@ class Pry
 
   # Load Readline history if required.
   def self.load_history
-    @loaded_history = []
-    if File.exists?(history_file)
-      File.foreach(history_file) do |line|
-        Readline::HISTORY << line.chomp
-        @loaded_history   << line.chomp
-      end
-    end
+    Pry.input_history.load(history_file) if File.exists?(history_file)
   end
 
   # Save new lines of Readline history if required.
   def self.save_history
-    history_to_save = Readline::HISTORY.to_a
-
-    # Omit any history we read from the file.This check is needed because
-    # `hist --clear` would otherwise cause us to not save history in this
-    # session.
-    if history_to_save[0...@loaded_history.size] == @loaded_history
-      history_to_save = history_to_save[@loaded_history.size..-1]
-    end
-
-    File.open(history_file, 'a') do |f|
-      f.puts history_to_save.join("\n") if history_to_save.size > 0
-    end
-
-    # Update @loaded_history so that future calls to save_history
-    # will do the right thing.
-    @loaded_history = Readline::HISTORY.to_a
+    Pry.input_history.save(history_file)
   end
 
   # Get the full path of the history_path for pry.
@@ -249,8 +231,9 @@ class Pry
   # Basic initialization.
   def self.init
     @plugin_manager ||= PluginManager.new
-
     self.config ||= Config.new
+    self.input_history ||= InputHistory.new
+
     reset_defaults
     locate_plugins
   end

lib/pry/pry_instance.rb

@@ -356,20 +356,6 @@ class Pry
       Pry.line_buffer.push(*code.each_line)
       Pry.current_line += code.each_line.count
     end
-    if Readline::HISTORY.size > 0
-
-      # all this fluff is to get around annoying bug in libedit on
-      # ruby 1.8.7
-      final_index = -1
-      begin
-        Readline::HISTORY[-1]
-      rescue IndexError
-        final_index = -2
-      end
-      last = Readline::HISTORY[final_index].strip
-      prev = Readline::HISTORY.size > 1 ? Readline::HISTORY[final_index - 1].strip : ''
-      Readline::HISTORY.pop if last && (last.empty? || last == prev)
-    end
   end
 
   # @return [Boolean] True if the last result is an exception that was raised,
@@ -386,10 +372,9 @@ class Pry
   def readline(current_prompt="> ")
 
     if input == Readline
-
-      # Readline must be treated differently
-      # as it has a second parameter.
-      input.readline(current_prompt, true)
+      line = input.readline(current_prompt, false)
+      Pry.input_history << line
+      line
     else
       begin
         if input.method(:readline).arity == 1

test/test_default_commands/test_input.rb

@@ -202,8 +202,8 @@ describe "Pry::DefaultCommands::Input" do
     end
 
     before do
-      Readline::HISTORY.shift until Readline::HISTORY.empty?
-      @hist = Readline::HISTORY
+      Pry.input_history.clear
+      @hist = Pry.input_history
     end
 
     it 'should display the correct history' do

test/test_pry_history.rb

@@ -4,7 +4,7 @@ require 'tempfile'
 describe Pry do
 
   before do
-    Readline::HISTORY.shift while Readline::HISTORY.length > 0
+    Pry.input_history.clear
     @hist = Tempfile.new(["tmp", ".pry_history"]).tap(&:close).path
     File.open(@hist, 'w') {|f| f << "1\n2\n3\n" }
     @old_hist = Pry.config.history.file
@@ -19,13 +19,13 @@ describe Pry do
 
   describe ".load_history" do
     it "should read the contents of the file" do
-      Readline::HISTORY.to_a[-2..-1].should === ["2", "3"]
+      Pry.input_history.to_a[-2..-1].should === ["2", "3"]
     end
   end
 
   describe ".save_history" do
     it "should include a trailing newline" do
-      Readline::HISTORY << "4"
+      Pry.input_history << "4"
       Pry.save_history
       File.read(@hist).should =~ /4\n\z/
     end
@@ -37,45 +37,45 @@ describe Pry do
     end
 
     it "should append new lines to the file" do
-      Readline::HISTORY << "4"
+      Pry.input_history << "4"
       Pry.save_history
       File.read(@hist).should == "1\n2\n3\n4\n"
     end
 
     it "should not clobber lines written by other Pry's in the meantime" do
-      Readline::HISTORY << "5"
+      Pry.input_history << "5"
       File.open(@hist, 'a') {|f| f << "4\n" }
       Pry.save_history
 
-      Readline::HISTORY.to_a[-3..-1].should == ["2", "3", "5"]
+      Pry.input_history.to_a[-3..-1].should == ["2", "3", "5"]
       File.read(@hist).should == "1\n2\n3\n4\n5\n"
     end
 
     it "should not delete lines from the file if this session's history was cleared" do
-      Readline::HISTORY.pop while Readline::HISTORY.size > 0
+      Pry.input_history.clear
       Pry.save_history
       File.read(@hist).should == "1\n2\n3\n"
     end
 
     it "should save new lines that are added after the history was cleared" do
-      Readline::HISTORY.pop while Readline::HISTORY.size > 0
-      Readline::HISTORY << "4"
+      Pry.input_history.clear
+      Pry.input_history << "4"
 
       # doing this twice as libedit on 1.8.7 has bugs and sometimes ignores the
       # first line in history
-      Readline::HISTORY << "4"
+      Pry.input_history << "4"
       Pry.save_history
       File.read(@hist).should =~ /1\n2\n3\n4\n/
     end
 
     it "should only append new lines the second time it is saved" do
-      Readline::HISTORY << "4"
+      Pry.input_history << "4"
       Pry.save_history
       File.open(@hist, 'a') {|f| f << "5\n" }
-      Readline::HISTORY << "6"
+      Pry.input_history << "6"
       Pry.save_history
 
-      Readline::HISTORY.to_a[-4..-1].should == ["2", "3", "4", "6"]
+      Pry.input_history.to_a[-4..-1].should == ["2", "3", "4", "6"]
       File.read(@hist).should == "1\n2\n3\n4\n5\n6\n"
     end
   end