Integrate Journey into Action Dispatch

Move the Journey code underneath the ActionDispatch namespace so
that we don't pollute the global namespace with names that may
be used for models.

Fixes rails/journey#49.

Author: pixeltrix

Gemfile

@@ -13,10 +13,12 @@ gem 'turbolinks'
 gem 'coffee-rails', github: 'rails/coffee-rails'
 
 gem 'thread_safe', '~> 0.1'
-gem 'journey', github: 'rails/journey', branch: 'master'
 
 gem 'activerecord-deprecated_finders', github: 'rails/activerecord-deprecated_finders', branch: 'master'
 
+# Needed for compiling the ActionDispatch::Journey parser
+gem 'racc', '>=1.4.6', require: false
+
 # This needs to be with require false to avoid
 # it being automatically loaded by sprockets
 gem 'uglifier', require: false

actionpack/CHANGELOG.md

@@ -1,5 +1,10 @@
 ## Rails 4.0.0 (unreleased) ##
 
+*   Integrate the Journey gem into Action Dispatch so that the global namespace
+    is not polluted with names that may be used as models.
+
+    *Andrew White*
+
 *   Extract support for email address obfuscation via `:encode`, `:replace_at`, and `replace_dot`
     options from the `mail_to` helper into the `actionview-encoded_mail_to` gem.
 

actionpack/Rakefile

@@ -15,7 +15,7 @@ Rake::TestTask.new(:test_action_pack) do |t|
 
   # make sure we include the tests in alphabetical order as on some systems
   # this will not happen automatically and the tests (as a whole) will error
-  t.test_files = Dir.glob('test/{abstract,controller,dispatch,template,assertions}/**/*_test.rb').sort
+  t.test_files = Dir.glob('test/{abstract,controller,dispatch,template,assertions,journey}/**/*_test.rb').sort
 
   t.warning = true
   t.verbose = true
@@ -75,3 +75,9 @@ task :lines do
 
   puts "Total: Lines #{total_lines}, LOC #{total_codelines}"
 end
+
+rule '.rb' => '.y' do |t|
+  sh "racc -l -o #{t.name} #{t.source}"
+end
+
+task :compile => 'lib/action_dispatch/journey/parser.rb'

actionpack/actionpack.gemspec

@@ -23,7 +23,6 @@ Gem::Specification.new do |s|
   s.add_dependency 'builder',       '~> 3.1.0'
   s.add_dependency 'rack',          '~> 1.4.1'
   s.add_dependency 'rack-test',     '~> 0.6.1'
-  s.add_dependency 'journey',       '~> 2.0.0'
   s.add_dependency 'erubis',        '~> 2.7.0'
 
   s.add_development_dependency 'activemodel', version

actionpack/lib/action_dispatch.rb

@@ -63,6 +63,7 @@ class IllegalStateError < StandardError
     autoload :Static
   end
 
+  autoload :Journey
   autoload :MiddlewareStack, 'action_dispatch/middleware/stack'
   autoload :Routing
 

actionpack/lib/action_dispatch/journey.rb

@@ -0,0 +1,5 @@
+require 'action_dispatch/journey/router'
+require 'action_dispatch/journey/gtg/builder'
+require 'action_dispatch/journey/gtg/simulator'
+require 'action_dispatch/journey/nfa/builder'
+require 'action_dispatch/journey/nfa/simulator'

actionpack/lib/action_dispatch/journey/backwards.rb

@@ -0,0 +1,5 @@
+module Rack
+  Mount = ActionDispatch::Journey::Router
+  Mount::RouteSet = ActionDispatch::Journey::Router
+  Mount::RegexpWithNamedGroups = ActionDispatch::Journey::Path::Pattern
+end

actionpack/lib/action_dispatch/journey/core-ext/hash.rb

@@ -0,0 +1,11 @@
+# :stopdoc:
+if RUBY_VERSION < '1.9'
+class Hash
+  def keep_if
+    each do |k,v|
+      delete(k) unless yield(k,v)
+    end
+  end
+end
+end
+# :startdoc:

actionpack/lib/action_dispatch/journey/formatter.rb

@@ -0,0 +1,147 @@
+module ActionDispatch
+  module Journey
+    ###
+    # The Formatter class is used for formatting URLs.  For example, parameters
+    # passed to +url_for+ in rails will eventually call Formatter#generate
+    class Formatter
+      attr_reader :routes
+
+      def initialize routes
+        @routes = routes
+        @cache  = nil
+      end
+
+      def generate type, name, options, recall = {}, parameterize = nil
+        constraints = recall.merge options
+        missing_keys = []
+
+        match_route(name, constraints) do |route|
+          parameterized_parts = extract_parameterized_parts route, options, recall, parameterize
+          next if !name && route.requirements.empty? && route.parts.empty?
+
+          missing_keys = missing_keys(route, parameterized_parts)
+          next unless missing_keys.empty?
+          params = options.dup.delete_if do |key, _|
+            parameterized_parts.key?(key) || route.defaults.key?(key)
+          end
+
+          return [route.format(parameterized_parts), params]
+        end
+
+        raise Router::RoutingError.new "missing required keys: #{missing_keys}"
+      end
+
+      def clear
+        @cache = nil
+      end
+
+      private
+      def extract_parameterized_parts route, options, recall, parameterize = nil
+        constraints = recall.merge options
+        data = constraints.dup
+
+        keys_to_keep = route.parts.reverse.drop_while { |part|
+          !options.key?(part) || (options[part] || recall[part]).nil?
+        } | route.required_parts
+
+        (data.keys - keys_to_keep).each do |bad_key|
+          data.delete bad_key
+        end
+
+        parameterized_parts = data.dup
+
+        if parameterize
+          parameterized_parts.each do |k,v|
+            parameterized_parts[k] = parameterize.call(k, v)
+          end
+        end
+
+        parameterized_parts.keep_if { |_,v| v  }
+        parameterized_parts
+      end
+
+      def named_routes
+        routes.named_routes
+      end
+
+      def match_route name, options
+        if named_routes.key? name
+          yield named_routes[name]
+        else
+          #routes = possibles(@cache, options.to_a)
+          routes = non_recursive(cache, options.to_a)
+
+          hash = routes.group_by { |_, r|
+            r.score options
+          }
+
+          hash.keys.sort.reverse_each do |score|
+            next if score < 0
+
+            hash[score].sort_by { |i,_| i }.each do |_,route|
+              yield route
+            end
+          end
+        end
+      end
+
+      def non_recursive cache, options
+        routes = []
+        stack  = [cache]
+
+        while stack.any?
+          c = stack.shift
+          routes.concat c[:___routes] if c.key? :___routes
+
+          options.each do |pair|
+            stack << c[pair] if c.key? pair
+          end
+        end
+
+        routes
+      end
+
+      # returns an array populated with missing keys if any are present
+      def missing_keys route, parts
+        missing_keys = []
+        tests = route.path.requirements
+        route.required_parts.each { |key|
+          if tests.key? key
+            missing_keys << key unless /\A#{tests[key]}\Z/ === parts[key]
+          else
+            missing_keys << key unless parts[key]
+          end
+        }
+        missing_keys
+      end
+
+      def possibles cache, options, depth = 0
+        cache.fetch(:___routes) { [] } + options.find_all { |pair|
+          cache.key? pair
+        }.map { |pair|
+          possibles(cache[pair], options, depth + 1)
+        }.flatten(1)
+      end
+
+      # returns boolean, true if no missing keys are present
+      def verify_required_parts! route, parts
+        missing_keys(route, parts).empty?
+      end
+
+      def build_cache
+        root = { :___routes => [] }
+        routes.each_with_index do |route, i|
+          leaf = route.required_defaults.inject(root) do |h, tuple|
+            h[tuple] ||= {}
+          end
+          (leaf[:___routes] ||= []) << [i, route]
+        end
+        root
+      end
+
+      def cache
+        @cache ||= build_cache
+      end
+    end
+  end
+end

actionpack/lib/action_dispatch/journey/gtg/builder.rb

@@ -0,0 +1,161 @@
+require 'action_dispatch/journey/gtg/transition_table'
+
+module ActionDispatch
+  module Journey
+    module GTG
+      class Builder
+        DUMMY = Nodes::Dummy.new # :nodoc:
+
+        attr_reader :root, :ast, :endpoints
+
+        def initialize root
+          @root         = root
+          @ast          = Nodes::Cat.new root, DUMMY
+          @followpos    = nil
+        end
+
+        def transition_table
+          dtrans   = TransitionTable.new
+          marked   = {}
+          state_id = Hash.new { |h,k| h[k] = h.length }
+
+          start   = firstpos(root)
+          dstates = [start]
+          until dstates.empty?
+            s = dstates.shift
+            next if marked[s]
+            marked[s] = true # mark s
+
+            s.group_by { |state| symbol(state) }.each do |sym, ps|
+              u = ps.map { |l| followpos(l) }.flatten
+              next if u.empty?
+
+              if u.uniq == [DUMMY]
+                from = state_id[s]
+                to   = state_id[Object.new]
+                dtrans[from, to] = sym
+
+                dtrans.add_accepting to
+                ps.each { |state| dtrans.add_memo to, state.memo }
+              else
+                dtrans[state_id[s], state_id[u]] = sym
+
+                if u.include? DUMMY
+                  to = state_id[u]
+
+                  accepting = ps.find_all { |l| followpos(l).include? DUMMY }
+
+                  accepting.each { |accepting_state|
+                    dtrans.add_memo to, accepting_state.memo
+                  }
+
+                  dtrans.add_accepting state_id[u]
+                end
+              end
+
+              dstates << u
+            end
+          end
+
+          dtrans
+        end
+
+        def nullable? node
+          case node
+          when Nodes::Group
+            true
+          when Nodes::Star
+            true
+          when Nodes::Or
+            node.children.any? { |c| nullable?(c) }
+          when Nodes::Cat
+            nullable?(node.left) && nullable?(node.right)
+          when Nodes::Terminal
+            !node.left
+          when Nodes::Unary
+            nullable? node.left
+          else
+            raise ArgumentError, 'unknown nullable: %s' % node.class.name
+          end
+        end
+
+        def firstpos node
+          case node
+          when Nodes::Star
+            firstpos(node.left)
+          when Nodes::Cat
+            if nullable? node.left
+              firstpos(node.left) | firstpos(node.right)
+            else
+              firstpos(node.left)
+            end
+          when Nodes::Or
+            node.children.map { |c| firstpos(c) }.flatten.uniq
+          when Nodes::Unary
+            firstpos(node.left)
+          when Nodes::Terminal
+            nullable?(node) ? [] : [node]
+          else
+            raise ArgumentError, 'unknown firstpos: %s' % node.class.name
+          end
+        end
+
+        def lastpos node
+          case node
+          when Nodes::Star
+            firstpos(node.left)
+          when Nodes::Or
+            node.children.map { |c| lastpos(c) }.flatten.uniq
+          when Nodes::Cat
+            if nullable? node.right
+              lastpos(node.left) | lastpos(node.right)
+            else
+              lastpos(node.right)
+            end
+          when Nodes::Terminal
+            nullable?(node) ? [] : [node]
+          when Nodes::Unary
+            lastpos(node.left)
+          else
+            raise ArgumentError, 'unknown lastpos: %s' % node.class.name
+          end
+        end
+
+        def followpos node
+          followpos_table[node]
+        end
+
+        private
+        def followpos_table
+          @followpos ||= build_followpos
+        end
+
+        def build_followpos
+          table = Hash.new { |h,k| h[k] = [] }
+          @ast.each do |n|
+            case n
+            when Nodes::Cat
+              lastpos(n.left).each do |i|
+                table[i] += firstpos(n.right)
+              end
+            when Nodes::Star
+              lastpos(n).each do |i|
+                table[i] += firstpos(n)
+              end
+            end
+          end
+          table
+        end
+
+        def symbol edge
+          case edge
+          when Journey::Nodes::Symbol
+            edge.regexp
+          else
+            edge.left
+          end
+        end
+      end
+    end
+  end
+end