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.

1 files changed, 44 insertions, 0 deletions

diff --git a/actionpack/lib/action_dispatch/journey/gtg/simulator.rb b/actionpack/lib/action_dispatch/journey/gtg/simulator.rb
new file mode 100644
index 0000000000..fda14c8680
--- /dev/null
+++ b/actionpack/lib/action_dispatch/journey/gtg/simulator.rb
@@ -0,0 +1,44 @@
+require 'strscan'
+
+module ActionDispatch
+  module Journey
+    module GTG
+      class MatchData
+        attr_reader :memos
+
+        def initialize memos
+          @memos = memos
+        end
+      end
+
+      class Simulator
+        attr_reader :tt
+
+        def initialize transition_table
+          @tt = transition_table
+        end
+
+        def simulate string
+          input = StringScanner.new string
+          state = [0]
+          while sym = input.scan(%r([/.?]|[^/.?]+))
+            state = tt.move(state, sym)
+          end
+
+          acceptance_states = state.find_all { |s|
+            tt.accepting? s
+          }
+
+          return if acceptance_states.empty?
+
+          memos = acceptance_states.map { |x| tt.memo x }.flatten.compact
+
+          MatchData.new memos
+        end
+
+        alias :=~    :simulate
+        alias :match :simulate
+      end
+    end
+  end
+end