1 files changed, 268 insertions, 0 deletions
diff --git a/actionpack/lib/action_controller/routing/segments.rb b/actionpack/lib/action_controller/routing/segments.rb
new file mode 100644
index 0000000000..efac2df1cb
--- /dev/null
+++ b/actionpack/lib/action_controller/routing/segments.rb
@@ -0,0 +1,268 @@
+module ActionController
+  module Routing
+    class Segment #:nodoc:
+      RESERVED_PCHAR = ':@&=+$,;'
+      UNSAFE_PCHAR = Regexp.new("[^#{URI::REGEXP::PATTERN::UNRESERVED}#{RESERVED_PCHAR}]", false, 'N').freeze
+
+      attr_accessor :is_optional
+      alias_method :optional?, :is_optional
+
+      def initialize
+        self.is_optional = false
+      end
+
+      def extraction_code
+        nil
+      end
+
+      # Continue generating string for the prior segments.
+      def continue_string_structure(prior_segments)
+        if prior_segments.empty?
+          interpolation_statement(prior_segments)
+        else
+          new_priors = prior_segments[0..-2]
+          prior_segments.last.string_structure(new_priors)
+        end
+      end
+
+      def interpolation_chunk
+        URI.escape(value, UNSAFE_PCHAR)
+      end
+
+      # Return a string interpolation statement for this segment and those before it.
+      def interpolation_statement(prior_segments)
+        chunks = prior_segments.collect { |s| s.interpolation_chunk }
+        chunks << interpolation_chunk
+        "\"#{chunks * ''}\"#{all_optionals_available_condition(prior_segments)}"
+      end
+
+      def string_structure(prior_segments)
+        optional? ? continue_string_structure(prior_segments) : interpolation_statement(prior_segments)
+      end
+
+      # Return an if condition that is true if all the prior segments can be generated.
+      # If there are no optional segments before this one, then nil is returned.
+      def all_optionals_available_condition(prior_segments)
+        optional_locals = prior_segments.collect { |s| s.local_name if s.optional? && s.respond_to?(:local_name) }.compact
+        optional_locals.empty? ? nil : " if #{optional_locals * ' && '}"
+      end
+
+      # Recognition
+
+      def match_extraction(next_capture)
+        nil
+      end
+
+      # Warning
+
+      # Returns true if this segment is optional? because of a default. If so, then
+      # no warning will be emitted regarding this segment.
+      def optionality_implied?
+        false
+      end
+    end
+
+    class StaticSegment < Segment #:nodoc:
+      attr_accessor :value, :raw
+      alias_method :raw?, :raw
+
+      def initialize(value = nil)
+        super()
+        self.value = value
+      end
+
+      def interpolation_chunk
+        raw? ? value : super
+      end
+
+      def regexp_chunk
+        chunk = Regexp.escape(value)
+        optional? ? Regexp.optionalize(chunk) : chunk
+      end
+
+      def build_pattern(pattern)
+        escaped = Regexp.escape(value)
+        if optional? && ! pattern.empty?
+          "(?:#{Regexp.optionalize escaped}\\Z|#{escaped}#{Regexp.unoptionalize pattern})"
+        elsif optional?
+          Regexp.optionalize escaped
+        else
+          escaped + pattern
+        end
+      end
+
+      def to_s
+        value
+      end
+    end
+
+    class DividerSegment < StaticSegment #:nodoc:
+      def initialize(value = nil)
+        super(value)
+        self.raw = true
+        self.is_optional = true
+      end
+
+      def optionality_implied?
+        true
+      end
+    end
+
+    class DynamicSegment < Segment #:nodoc:
+      attr_accessor :key, :default, :regexp
+
+      def initialize(key = nil, options = {})
+        super()
+        self.key = key
+        self.default = options[:default] if options.key? :default
+        self.is_optional = true if options[:optional] || options.key?(:default)
+      end
+
+      def to_s
+        ":#{key}"
+      end
+
+      # The local variable name that the value of this segment will be extracted to.
+      def local_name
+        "#{key}_value"
+      end
+
+      def extract_value
+        "#{local_name} = hash[:#{key}] && hash[:#{key}].to_param #{"|| #{default.inspect}" if default}"
+      end
+      def value_check
+        if default # Then we know it won't be nil
+          "#{value_regexp.inspect} =~ #{local_name}" if regexp
+        elsif optional?
+          # If we have a regexp check that the value is not given, or that it matches.
+          # If we have no regexp, return nil since we do not require a condition.
+          "#{local_name}.nil? || #{value_regexp.inspect} =~ #{local_name}" if regexp
+        else # Then it must be present, and if we have a regexp, it must match too.
+          "#{local_name} #{"&& #{value_regexp.inspect} =~ #{local_name}" if regexp}"
+        end
+      end
+      def expiry_statement
+        "expired, hash = true, options if !expired && expire_on[:#{key}]"
+      end
+
+      def extraction_code
+        s = extract_value
+        vc = value_check
+        s << "\nreturn [nil,nil] unless #{vc}" if vc
+        s << "\n#{expiry_statement}"
+      end
+
+      def interpolation_chunk(value_code = "#{local_name}")
+        "\#{URI.escape(#{value_code}.to_s, ActionController::Routing::Segment::UNSAFE_PCHAR)}"
+      end
+
+      def string_structure(prior_segments)
+        if optional? # We have a conditional to do...
+          # If we should not appear in the url, just write the code for the prior
+          # segments. This occurs if our value is the default value, or, if we are
+          # optional, if we have nil as our value.
+          "if #{local_name} == #{default.inspect}\n" +
+            continue_string_structure(prior_segments) +
+          "\nelse\n" + # Otherwise, write the code up to here
+            "#{interpolation_statement(prior_segments)}\nend"
+        else
+          interpolation_statement(prior_segments)
+        end
+      end
+
+      def value_regexp
+        Regexp.new "\\A#{regexp.source}\\Z" if regexp
+      end
+      def regexp_chunk
+        regexp ? "(#{regexp.source})" : "([^#{Routing::SEPARATORS.join}]+)"
+      end
+
+      def build_pattern(pattern)
+        chunk = regexp_chunk
+        chunk = "(#{chunk})" if Regexp.new(chunk).number_of_captures == 0
+        pattern = "#{chunk}#{pattern}"
+        optional? ? Regexp.optionalize(pattern) : pattern
+      end
+      def match_extraction(next_capture)
+        # All non code-related keys (such as :id, :slug) are URI-unescaped as
+        # path parameters.
+        default_value = default ? default.inspect : nil
+        %[
+          value = if (m = match[#{next_capture}])
+            URI.unescape(m)
+          else
+            #{default_value}
+          end
+          params[:#{key}] = value if value
+        ]
+      end
+
+      def optionality_implied?
+        [:action, :id].include? key
+      end
+
+    end
+
+    class ControllerSegment < DynamicSegment #:nodoc:
+      def regexp_chunk
+        possible_names = Routing.possible_controllers.collect { |name| Regexp.escape name }
+        "(?i-:(#{(regexp || Regexp.union(*possible_names)).source}))"
+      end
+
+      # Don't URI.escape the controller name since it may contain slashes.
+      def interpolation_chunk(value_code = "#{local_name}")
+        "\#{#{value_code}.to_s}"
+      end
+
+      # Make sure controller names like Admin/Content are correctly normalized to
+      # admin/content
+      def extract_value
+        "#{local_name} = (hash[:#{key}] #{"|| #{default.inspect}" if default}).downcase"
+      end
+
+      def match_extraction(next_capture)
+        if default
+          "params[:#{key}] = match[#{next_capture}] ? match[#{next_capture}].downcase : '#{default}'"
+        else
+          "params[:#{key}] = match[#{next_capture}].downcase if match[#{next_capture}]"
+        end
+      end
+    end
+
+    class PathSegment < DynamicSegment #:nodoc:
+      RESERVED_PCHAR = "#{Segment::RESERVED_PCHAR}/"
+      UNSAFE_PCHAR = Regexp.new("[^#{URI::REGEXP::PATTERN::UNRESERVED}#{RESERVED_PCHAR}]", false, 'N').freeze
+
+      def interpolation_chunk(value_code = "#{local_name}")
+        "\#{URI.escape(#{value_code}.to_s, ActionController::Routing::PathSegment::UNSAFE_PCHAR)}"
+      end
+
+      def default
+        ''
+      end
+
+      def default=(path)
+        raise RoutingError, "paths cannot have non-empty default values" unless path.blank?
+      end
+
+      def match_extraction(next_capture)
+        "params[:#{key}] = PathSegment::Result.new_escaped((match[#{next_capture}]#{" || " + default.inspect if default}).split('/'))#{" if match[" + next_capture + "]" if !default}"
+      end
+
+      def regexp_chunk
+        regexp || "(.*)"
+      end
+
+      def optionality_implied?
+        true
+      end
+
+      class Result < ::Array #:nodoc:
+        def to_s() join '/' end
+        def self.new_escaped(strings)
+          new strings.collect {|str| URI.unescape str}
+        end
+      end
+    end
+  end
+end