lib/codependency/graph.rb in codependency-0.2.0 vs lib/codependency/graph.rb in codependency-0.3.0

@@ -1,30 +1,45 @@
+require 'open3'
+
 module Codependency
   class Graph
     def initialize( start, options={} )
       @options = options
       @nodes   = Hash.new { |h, k| h[ k ] = Node.new( k, parser ) }
       @start   = @nodes[ start ]
     end
 
+    ##
+    # a topologically sorted list of all dependencies of the `start` file.
     def files
-      [ ].tap { |list| resolve @start, list }.reverse.map &:filename
+      deps = resolve( @start, [ ] ).map( &:dependencies ).join ' '
+
+      cmd, out, err = Open3.popen3 "echo '#{deps}' | tsort"
+
+      if msg = err.gets
+        raise CircularDependencyError, msg
+      end
+
+      out.readlines.map( &:chomp ).reverse
     end
 
     protected
 
+    ##
+    # adds a node's dependencies to a list (memo).
+    # intended to be used recursively.
     def resolve( node, list )
-      list << node # TODO if the node were in the list here,
-                   # would that indicate a circular dependency?
-      node.dependencies.map { |filename| @nodes[ filename ] }.each do |dep|
-        if list.include?( dep )
-          list << list.slice!( list.index( dep ) )
-        else
-          resolve dep, list
-        end
+      list << node
+
+      node.edges.map { |filename| @nodes[ filename ] }.each do |dep|
+        resolve dep, list unless list.include?( dep )
       end
+
+      list
     end
 
+    ##
+    # the parser to use for this graph. shared by all nodes.
     def parser
       @parser ||= Parser.new @options
     end
   end
 end