moved Pry#complete_expression? et al to Pry::Code

* This is so we can use it without needing a Pry instance present, it also feels like a more natural home for it.

lib/pry/code.rb

@@ -27,6 +27,71 @@ class Pry
   # object.
   class Code
     class << self
+
+      # Determine if a string of code is a complete Ruby expression.
+      # @param [String] code The code to validate.
+      # @return [Boolean] Whether or not the code is a complete Ruby expression.
+      # @raise [SyntaxError] Any SyntaxError that does not represent incompleteness.
+      # @example
+      #   complete_expression?("class Hello") #=> false
+      #   complete_expression?("class Hello; end") #=> true
+      def complete_expression?(str)
+        if defined?(Rubinius::Melbourne19) && RUBY_VERSION =~ /^1\.9/
+          Rubinius::Melbourne19.parse_string(str, Pry.eval_path)
+        elsif defined?(Rubinius::Melbourne)
+          Rubinius::Melbourne.parse_string(str, Pry.eval_path)
+        else
+          catch(:valid) do
+            Helpers::BaseHelpers.silence_warnings do
+              eval("BEGIN{throw :valid}\n#{str}", binding, Pry.eval_path)
+            end
+          end
+        end
+
+        # Assert that a line which ends with a , is incomplete.
+        str !~ /[,]\z/
+      rescue SyntaxError => e
+        if incomplete_user_input_exception?(e)
+          false
+        else
+          raise e
+        end
+      end
+
+      # Check whether the exception indicates that the user should input more.
+      #
+      # @param [SyntaxError] the exception object that was raised.
+      # @param [Array<String>] The stack frame of the function that executed eval.
+      # @return [Boolean]
+      #
+      def incomplete_user_input_exception?(ex)
+        case ex.message
+        when /unexpected (\$end|end-of-file|END_OF_FILE)/, # mri, jruby, ironruby
+          /unterminated (quoted string|string|regexp) meets end of file/, # "quoted string" is ironruby
+          /missing 'end' for/, /: expecting '[})\]]'$/, /can't find string ".*" anywhere before EOF/, /: expecting keyword_end/ # rbx
+          true
+        else
+          false
+        end
+      end
+
+      # Retrieve the first complete expression from the passed string.
+      #
+      # @param [String, Array<String>] str The string (or array of lines) to extract the complete
+      #   expression from.
+      # @return [String, nil] The first complete expression, or `nil` if
+      #   none found.
+      def retrieve_complete_expression_from(str_or_lines)
+        lines = str_or_lines.is_a?(Array) ? str_or_lines : str.each_line.to_a
+
+        code = ""
+        lines.each do |v|
+          code << v
+          return code if complete_expression?(code)
+        end
+        nil
+      end
+
       # Instantiate a `Code` object containing code loaded from a file or
       # Pry's line buffer.
       #

lib/pry/command.rb

@@ -322,7 +322,7 @@ class Pry
       block_init_string = arg_string.slice!(block_index..-1)[1..-1]
       prime_string = "proc #{block_init_string}\n"
 
-      if !_pry_.complete_expression?(prime_string)
+      if !Pry::Code.complete_expression?(prime_string)
         block_string = _pry_.r(target, prime_string)
       else
         block_string = prime_string

lib/pry/default_commands/editing.rb

@@ -379,7 +379,7 @@ class Pry
 
         def process
           perform_play
-          run "show-input" unless _pry_.complete_expression?(eval_string)
+          run "show-input" unless Pry::Code.complete_expression?(eval_string)
         end
 
         def process_non_opt

lib/pry/pry_instance.rb

@@ -293,7 +293,7 @@ class Pry
       end
 
       begin
-        break if complete_expression?(eval_string)
+        break if Pry::Code.complete_expression?(eval_string)
       rescue SyntaxError => e
         output.puts "SyntaxError: #{e.message.sub(/.*syntax error, */m, '')}"
         eval_string = ""
@@ -635,53 +635,6 @@ class Pry
     prompt_stack.size > 1 ? prompt_stack.pop : prompt
   end
 
-  # Determine if a string of code is a complete Ruby expression.
-  # @param [String] code The code to validate.
-  # @return [Boolean] Whether or not the code is a complete Ruby expression.
-  # @raise [SyntaxError] Any SyntaxError that does not represent incompleteness.
-  # @example
-  #   complete_expression?("class Hello") #=> false
-  #   complete_expression?("class Hello; end") #=> true
-  def complete_expression?(str)
-    if defined?(Rubinius::Melbourne19) && RUBY_VERSION =~ /^1\.9/
-      Rubinius::Melbourne19.parse_string(str, Pry.eval_path)
-    elsif defined?(Rubinius::Melbourne)
-      Rubinius::Melbourne.parse_string(str, Pry.eval_path)
-    else
-      catch(:valid) do
-        Helpers::BaseHelpers.silence_warnings do
-          eval("BEGIN{throw :valid}\n#{str}", binding, Pry.eval_path)
-        end
-      end
-    end
-
-    # Assert that a line which ends with a , is incomplete.
-    str !~ /[,]\z/
-  rescue SyntaxError => e
-    if incomplete_user_input_exception?(e)
-      false
-    else
-      raise e
-    end
-  end
-
-  # Check whether the exception indicates that the user should input more.
-  #
-  # @param [SyntaxError] the exception object that was raised.
-  # @param [Array<String>] The stack frame of the function that executed eval.
-  # @return [Boolean]
-  #
-  def incomplete_user_input_exception?(ex)
-    case ex.message
-    when /unexpected (\$end|end-of-file|END_OF_FILE)/, # mri, jruby, ironruby
-        /unterminated (quoted string|string|regexp) meets end of file/, # "quoted string" is ironruby
-        /missing 'end' for/, /: expecting '[})\]]'$/, /can't find string ".*" anywhere before EOF/, /: expecting keyword_end/ # rbx
-      true
-    else
-      false
-    end
-  end
-
   # Raise an exception out of Pry.
   #
   # See Kernel#raise for documentation of parameters.

test/test_pry.rb

@@ -188,7 +188,7 @@ describe Pry do
         it "should not mutate the input!" do
           clean = "puts <<-FOO\nhi\nFOO\n"
           a = clean.dup
-          Pry.new.complete_expression?(a)
+          Pry::Code.complete_expression?(a)
           a.should == clean
         end
       end

test/test_syntax_checking.rb

@@ -49,12 +49,12 @@ describe Pry do
   it "should allow trailing , to continue the line" do
     pry = Pry.new
 
-    pry.complete_expression?("puts 1, 2,").should == false
+    Pry::Code.complete_expression?("puts 1, 2,").should == false
   end
 
   it "should complete an expression that contains a line ending with a ," do
     pry = Pry.new
-    pry.complete_expression?("puts 1, 2,\n3").should == true
+    Pry::Code.complete_expression?("puts 1, 2,\n3").should == true
   end
 
   it "should not clobber _ex_ on a SyntaxError in the repl" do