Make Parser#output alias of Parser#run

This also makes sure that output is only calculated once.

Author: paulgoetze

lib/code_breaker/parser.rb

@@ -4,26 +4,30 @@
 module CodeBreaker
   class Parser
 
-    attr_reader :input, :output
+    attr_reader :input
 
     def initialize(code)
       @input = code.to_s.strip
     end
 
     def run
-      parsed = ::Parser::CurrentRuby.parse(@input)
-      nodes = parsed.loc.node.children
-      children = nodes[1].children
-
-      result = parse(children)
-      @output = cleanup(result)
+      @output ||= parse(@input)
     end
 
+    alias :output :run
+
     private
 
-    def parse(nodes)
+    def parse(input)
+      parsed_ast = ::Parser::CurrentRuby.parse(input)
+      nodes = parsed_ast.loc.node.children[1].children
+      result = parse_nodes(nodes)
+      cleanup(result)
+    end
+
+    def parse_nodes(nodes)
       nodes.map do |node|
-        node.respond_to?(:children) ? parse(node.children).to_a : node
+        node.respond_to?(:children) ? parse_nodes(node.children).to_a : node
       end
     end
 

spec/parser_spec.rb

@@ -2,13 +2,27 @@
 
 describe CodeBreaker::Parser do
 
-  let(:code_snippet) { 'gem_name = "code_breaker"' }
+  let(:code_snippet) { 'sum = "2".to_i + 3' }
+  let(:output) { [String, :to_i, :+, Fixnum] }
+
   subject { CodeBreaker::Parser.new(code_snippet) }
 
   it { is_expected.to respond_to :run }
   it { is_expected.to respond_to :input }
   it { is_expected.to respond_to :output }
 
+  describe 'input' do
+    it 'returns the code snippet the parser was instanciated with' do
+      expect(subject.input).to eq code_snippet
+    end
+  end
+
+  describe 'output' do
+    it 'is an alias method for #run' do
+      expect(subject.method(:output)).to eq subject.method(:run)
+    end
+  end
+
   describe '#run' do
     it 'returns an Array' do
       expect(subject.run).to be_an Array