Commit c6a285d2 authored by Rene Saarsoo's avatar Rene Saarsoo
Browse files

Extract ScopedTraverser class. 

Move common functionality from Fires and MethodCalls to
ScopedTraverser, which provides the ability to loop recursively
through AST tree while keeping track of the variables bound
to `this`.
parent 85cc9795

lib/jsduck/js/fires.rb

+8 −24
Original line number Diff line number Diff line 
require "jsduck/util/singleton"

require "jsduck/js/scoped_traverser"



module JsDuck

  module Js
@@ -10,49 +11,32 @@ module JsDuck 


      # Returns array of event names fired by the given function.

      # When no events fired, empty array is returned.

      def detect(node)

        @this_map = {

          "this" => true

        }

      def detect(function_node)

        @traverser = Js::ScopedTraverser.new



        detect_body(node["body"]["body"]).sort.uniq

      end



      private



      def detect_body(body_nodes)

        events = []



        body_nodes.each do |node|

        @traverser.traverse(function_node["body"]) do |node|

          if fire_event?(node)

            events << node["arguments"][0].to_value

          elsif this_var?(node)

            var_name = node["id"].to_s

            @this_map[var_name] = true

          else

            events.concat(detect_body(node.body))

          end

        end



        events

        events.sort.uniq

      end



      private



      # True when node is this.fireEvent("name") call.

      # Also true for me.fireEvent() when me == this.

      def fire_event?(node)

        node.call_expression? &&

          node["callee"].member_expression? &&

          @this_map[node["callee"]["object"].to_s] &&

          @traverser.this?(node["callee"]["object"].to_s) &&

          node["callee"]["property"].to_s == "fireEvent" &&

          node["arguments"].length > 0 &&

          node["arguments"][0].value_type == "String"

      end



      # True when initialization of variable with `this`

      def this_var?(node)

        node.type == "VariableDeclarator" && node["init"].type == "ThisExpression"

      end



    end

  end

end

lib/jsduck/js/method_calls.rb

+8 −26
Original line number Diff line number Diff line 
require "jsduck/util/singleton"

require "jsduck/js/scoped_traverser"



module JsDuck

  module Js
@@ -10,34 +11,20 @@ module JsDuck 


      # Returns array of method names called by the given function.

      # When no methods called, empty array is returned.

      def detect(node)

        @this_map = {

          "this" => true

        }

      def detect(function_node)

        @traverser = Js::ScopedTraverser.new



        detect_body(node["body"]["body"]).sort.uniq

      end



      private



      def detect_body(body_nodes)

        methods = []



        body_nodes.each do |node|

        @traverser.traverse(function_node["body"]) do |node|

          if method_call?(node)

            methods << node["callee"]["property"].to_s

          end



          if this_var?(node)

            var_name = node["id"].to_s

            @this_map[var_name] = true

        end



          methods.concat(detect_body(node.body))

        methods.sort.uniq

      end



        methods

      end

      private



      # True when node is this.someMethod() call.

      # Also true for me.someMethod() when me == this.
@@ -45,12 +32,7 @@ module JsDuck 
        node.call_expression? &&

          node["callee"].member_expression? &&

          node["callee"].raw["computed"] == false &&

          @this_map[node["callee"]["object"].to_s]

      end



      # True when initialization of variable with `this`

      def this_var?(node)

        node.type == "VariableDeclarator" && node["init"].type == "ThisExpression"

          @traverser.this?(node["callee"]["object"].to_s)

      end



    end

lib/jsduck/js/scoped_traverser.rb

0 → 100644
+42 −0
Original line number Diff line number Diff line 
module JsDuck

  module Js



    # Traverses syntax tree while keeping track of variables that are

    # bound to `this`.

    class ScopedTraverser

      def initialize

        @this_map = {

          "this" => true

        }

      end



      # Loops recursively over all the sub-nodes of the given node,

      # calling the provided block for each sub-node.

      def traverse(node, &block)

        node.body.each do |child|

          yield child



          if this_var?(child)

            var_name = child["id"].to_s

            @this_map[var_name] = true

          end



          traverse(child, &block)

        end

      end



      # True when variable with given name is bound to `this`.

      def this?(var_name)

        @this_map[var_name]

      end



      private



      # True when initialization of variable with `this`

      def this_var?(node)

        node.type == "VariableDeclarator" && node["init"].type == "ThisExpression"

      end



    end

  end

end