irb/{context,workspace}.rb: use local_variable_set

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@63149 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

lib/irb/context.rb

@@ -262,7 +262,7 @@ module IRB
     # to #last_value.
     def set_last_value(value)
       @last_value = value
-      @workspace.evaluate self, "_ = IRB.CurrentContext.last_value"
+      @workspace.local_variable_set :_, value
     end
 
     # Sets the +mode+ of the prompt in this context.

lib/irb/workspace.rb

@@ -71,7 +71,7 @@ EOF
           end
         end
       end
-      eval("_=nil", @binding)
+      @binding.local_variable_set(:_, nil)
     end
 
     # The Binding of this workspace
@@ -85,6 +85,14 @@ EOF
       eval(statements, @binding, file, line)
     end
 
+    def local_variable_set(name, value)
+      @binding.local_variable_set(name, value)
+    end
+
+    def local_variable_get(name)
+      @binding.local_variable_get(name)
+    end
+
     # error message manipulator
     def filter_backtrace(bt)
       case IRB.conf[:CONTEXT_MODE]

test/irb/test_context.rb

@@ -0,0 +1,44 @@
+# frozen_string_literal: false
+require 'test/unit'
+require 'tempfile'
+require 'irb'
+require 'rubygems' if defined?(Gem)
+
+module TestIRB
+  class TestContext < Test::Unit::TestCase
+    class TestInputMethod < ::IRB::InputMethod
+      attr_reader :line, :line_no
+
+      def initialize(list = [])
+        super("test")
+        @line_no = 0
+        @line = list
+      end
+
+      def gets
+        @list[@line_no.tap {@line_no += 1}]
+      end
+
+      def eof?
+        @line_no >= @list.size
+      end
+    end
+
+    def setup
+      IRB.init_config(nil)
+      IRB.conf[:USE_READLINE] = false
+      IRB.conf[:VERBOSE] = false
+      workspace = IRB::WorkSpace.new(Object.new)
+      @context = IRB::Context.new(nil, workspace, TestInputMethod.new)
+    end
+
+    def test_last_value
+      assert_nil(@context.last_value)
+      assert_nil(@context.evaluate('_', 1))
+      obj = Object.new
+      @context.set_last_value(obj)
+      assert_same(obj, @context.last_value)
+      assert_same(obj, @context.evaluate('_', 1))
+    end
+  end
+end