modify edit-method -p to support aliased methods that use super

lib/pry/default_commands/introspection.rb

@@ -225,8 +225,9 @@ class Pry
         if opts.p? || meth.dynamically_defined?
           lines = meth.source.lines.to_a
 
-          if lines[0] =~ /^def [^( \n]+/
-            lines[0] = "def #{meth.name}#{$'}"
+          if ((original_name = meth.original_name) &&
+              lines[0] =~ /^def (?:.*?\.)?#{original_name}(?=[\( ]|$)/)
+            lines[0] = "def #{original_name}#{$'}"
           else
             raise CommandError, "Pry can only patch methods created with the `def` keyword."
           end
@@ -235,7 +236,15 @@ class Pry
             f.puts lines.join
             f.flush
             invoke_editor(f.path, 0)
-            Pry.new(:input => StringIO.new(File.read(f.path))).rep(meth.owner)
+
+            if meth.alias?
+              with_method_transaction(original_name, meth.owner) do
+                Pry.new(:input => StringIO.new(File.read(f.path))).rep(meth.owner)
+                Pry.binding_for(meth.owner).eval("alias #{meth.name} #{original_name}")
+              end
+            else
+              Pry.new(:input => StringIO.new(File.read(f.path))).rep(meth.owner)
+            end
           end
           next
         end
@@ -252,6 +261,17 @@ class Pry
         end
       end
 
+      helpers do
+        def with_method_transaction(meth_name, target=TOPLEVEL_BINDING)
+          target = Pry.binding_for(target)
+          temp_name = "__pry_#{meth_name}__"
+
+          target.eval("alias #{temp_name} #{meth_name}")
+          yield
+          target.eval("alias #{meth_name} #{temp_name}")
+          target.eval("undef #{temp_name}")
+        end
+      end
     end
   end
 end

lib/pry/method.rb

@@ -265,7 +265,7 @@ class Pry
       "#{name}(#{args.join(', ')})"
     end
 
-    # @return [Pry::Method, nil] The wrapped method that get's called when you
+    # @return [Pry::Method, nil] The wrapped method that is called when you
     #   use "super" in the body of this method.
     def super(times=1)
       if respond_to?(:receiver)
@@ -277,6 +277,35 @@ class Pry
       Pry::Method.new(sup) if sup
     end
 
+    # @return [Symbol, nil] The original name the method was defined under,
+    #   before any aliasing, or `nil` if it can't be determined.
+    def original_name
+      return nil if source_type != :ruby
+
+      first_line = source.lines.first
+      return nil if first_line.strip !~ /^def /
+
+      if RUBY_VERSION =~ /^1\.9/ && RUBY_ENGINE == "ruby"
+        require 'ripper'
+
+        tree = Ripper::SexpBuilder.new(first_line + ";end").parse
+        name = tree.flatten(2).each do |lst|
+          break lst[1] if lst[0] == :@ident
+        end
+
+        name.is_a?(String) ? name : nil
+      else
+        require 'ruby_parser'
+
+        tree = RubyParser.new.parse(first_line + ";end")
+        name = tree.each_cons(2) do |a, b|
+          break a if b.is_a?(Array) && b.first == :args
+        end
+
+        name.is_a?(Symbol) ? name.to_s : nil
+      end
+    end
+
     # @return [Boolean] Was the method defined outside a source file?
     def dynamically_defined?
       !!(source_file and source_file =~ /(\(.*\))|<.*>/)
@@ -287,6 +316,11 @@ class Pry
       source_file == Pry.eval_path
     end
 
+    # @return [Boolean] Is the method definitely an alias?
+    def alias?
+      name != original_name
+    end
+
     # @return [Boolean]
     def ==(obj)
       if obj.is_a? Pry::Method

test/test_default_commands/test_introspection.rb

@@ -370,6 +370,10 @@ describe "Pry::DefaultCommands::Introspection" do
             def a
               :yup
             end
+
+            def b
+              :kinda
+            end
           end
 
           class X
@@ -382,6 +386,11 @@ describe "Pry::DefaultCommands::Introspection" do
             def x
               :nope
             end
+
+            def b
+              super
+            end
+            alias c b
           end
         EOS
         @tempfile.flush
@@ -408,19 +417,19 @@ describe "Pry::DefaultCommands::Introspection" do
         it "should correctly find a class method" do
           mock_pry("edit-method X.x")
           @file.should == @tempfile.path
-          @line.should == 10
+          @line.should == 14
         end
 
         it "should correctly find an instance method" do
           mock_pry("edit-method X#x")
           @file.should == @tempfile.path
-          @line.should == 14
+          @line.should == 18
         end
 
         it "should correctly find a method on an instance" do
           mock_pry("x = X.new", "edit-method x.x")
           @file.should == @tempfile.path
-          @line.should == 14
+          @line.should == 18
         end
 
         it "should correctly find a method from a module" do
@@ -428,6 +437,12 @@ describe "Pry::DefaultCommands::Introspection" do
           @file.should == @tempfile.path
           @line.should == 2
         end
+
+        it "should correctly find an aliased method" do
+          mock_pry("edit-method X#c")
+          @file.should == @tempfile.path
+          @line.should == 22
+        end
       end
 
       describe 'with -p' do
@@ -478,6 +493,32 @@ describe "Pry::DefaultCommands::Introspection" do
           X.new.a.should == :maybe
         end
       end
+
+      describe 'on an aliased method' do
+        before do
+          @old_editor = Pry.config.editor
+          Pry.config.editor = lambda do |file, line|
+            lines = File.read(file).lines.to_a
+            lines[1] = '"#{super}aa".to_sym' + "\n"
+            File.open(file, 'w') do |f|
+              f.write(lines.join)
+            end
+            nil
+          end
+        end
+        after do
+          Pry.config.editor = @old_editor
+        end
+
+        it "should change the alias, but not the original, without breaking super" do
+          mock_pry("edit-method -p X#c")
+
+          Pry::Method.from_str("X#c").alias?.should == true
+
+          X.new.b.should == :kinda
+          X.new.c.should == :kindaaa
+        end
+      end
     end
   end