Command::Hist: change the behaviour

Fix issue #205 (history option to show just history for current session)

Add `--all` switch. `hist` is `hist --all` now. `hist` without any
parameters shows the history of the current session.

lib/pry/commands/hist.rb

@@ -6,6 +6,7 @@ class Pry
 
     banner <<-'BANNER'
       Usage:   hist [--head|--tail]
+               hist --all
                hist --head N
                hist --tail N
                hist --show START..END
@@ -19,6 +20,7 @@ class Pry
     BANNER
 
     def options(opt)
+      opt.on :a, :all,    "Display all history"
       opt.on :H, :head,   "Display the first N items", :optional_argument => true, :as => Integer
       opt.on :T, :tail,   "Display the last N items", :optional_argument => true, :as => Integer
       opt.on :s, :show,   "Show the given range of lines", :optional_argument => true, :as => Range
@@ -32,8 +34,7 @@ class Pry
     end
 
     def process
-      # The last value in history will be the 'hist' command itself
-      @history = Pry::Code(Pry.history.to_a[0..-2])
+      @history = find_history
 
       if opts.present?(:show)
         @history = @history.between(opts[:show])
@@ -156,6 +157,21 @@ class Pry
         false
       end
     end
+
+    # Finds history depending on the given switch.
+    #
+    # @return [Pry::Code] if it finds `--all` (or `-a`) switch, returns all
+    #   entries in history. Without the switch returns only the entries from the
+    #   current Pry session.
+    def find_history
+      h = if opts.present?(:all)
+            Pry.history.to_a
+          else
+            Pry.history.to_a.last(Pry.history.session_line_count)
+          end
+      # The last value in history will be the 'hist' command itself.
+      Pry::Code(h[0..-2])
+    end
   end
 
   Pry::Commands.add_command(Pry::Command::Hist)

spec/commands/hist_spec.rb

@@ -7,22 +7,14 @@ describe "hist" do
 
     @str_output = StringIO.new
     @t = pry_tester :history => @hist do
-      # For looking at what hist pushes into the input stack. The
-      # implementation of this helper will definitely have to change at some
-      # point.
+      # For looking at what hist pushes into the input stack. The implementation
+      # of this helper will definitely have to change at some point.
       def next_input
         @pry.input.string
       end
     end
   end
 
-  it 'should display the correct history' do
-    @hist.push "hello"
-    @hist.push "world"
-
-    @t.eval('hist').should =~ /hello\n.*world/
-  end
-
   it 'should replay history correctly (single item)' do
     o = Object.new
     @hist.push "@x = 10"
@@ -175,4 +167,32 @@ describe "hist" do
     @hist.push('ls')
     pry_eval('hist -e').should == "1: a = 20\n"
   end
+
+  describe "sessions" do
+    before do
+      @old_file = Pry.config.history.file
+      Pry.config.history.file = File.expand_path('spec/fixtures/pry_history')
+      @hist.load
+    end
+
+    after do
+      Pry.config.history.file = @old_file
+    end
+
+    it "displays history only for current session" do
+      @hist.push('hello')
+      @hist.push('world')
+
+      @t.eval('hist').should =~ /1:\shello\n2:\sworld/
+    end
+
+    it "displays all history (including the current sesion) with `--all` switch" do
+      @hist.push('goodbye')
+      @hist.push('world')
+
+      output = @t.eval('hist --all')
+      output.should =~ /1:\s:athos\n2:\s:porthos\n3:\s:aramis\n/
+      output.should =~ /4:\sgoodbye\n5:\sworld/
+    end
+  end
 end

spec/fixtures/pry_history

@@ -0,0 +1,3 @@
+:athos
+:porthos
+:aramis