labels.rb in neo4j-3.0.0.rc.2

- old
+ new

@@ -7,10 +7,11 @@
       extend ActiveSupport::Concern
 
       WRAPPED_CLASSES = []
       class InvalidQueryError < StandardError; end
       class RecordNotFound < StandardError; end
+      class InvalidParameterError < StandardError; end
 
       # @return the labels
       # @see Neo4j-core
       def labels
         @_persisted_obj.labels
@@ -69,18 +70,39 @@
           self.query_as(:n).limit(1).order('ID(n)').pluck(:n).first
         end
 
         # Returns the last node of this class, sorted by ID. Note that this may not be the first node created since Neo4j recycles IDs.
         def last
-          self.query_as(:n).order('ID(n) DESC').limit(1).pluck(:n).first
+          self.query_as(:n).limit(1).order('ID(n) DESC').pluck(:n).first
         end
 
         # @return [Fixnum] number of nodes of this class
-        def count
-          self.query_as(:n).return("count(n) AS count").first.count
+        def count(distinct = nil)
+          raise(InvalidParameterError, ':count accepts `distinct` or nil as a parameter') unless distinct.nil? || distinct == :distinct
+          q = distinct.nil? ? "n" : "DISTINCT n"
+          self.query_as(:n).return("count(#{q}) AS count").first.count
         end
+        alias_method :size,   :count
+        alias_method :length, :count
 
+        def empty?
+          !self.exists?
+        end
+        alias_method :blank?, :empty?
+
+        def include?(other)
+          raise(InvalidParameterError, ':include? only accepts nodes') unless other.respond_to?(:neo_id)
+          self.query_as(:n).where("ID(n) = #{other.neo_id}").return("count(n) AS count").first.count > 0
+        end
+
+        def exists?(node_id=nil)
+          raise(InvalidParameterError, ':exists? only accepts neo_ids') unless node_id.is_a?(Integer) || node_id.nil?
+          start_q = self.query_as(:n)
+          end_q = node_id.nil? ? start_q : start_q.where("ID(n) = #{node_id}")
+          end_q.return("COUNT(n) AS count").first.count > 0
+        end
+
         # Returns the object with the specified neo4j id.
         # @param [String,Fixnum] id of node to find
         def find(id)
           raise "Unknown argument #{id.class} in find method (expected String or Fixnum)" if not [String, Fixnum].include?(id.class)
           find_by_id(id)
@@ -145,20 +167,20 @@
             label.create_constraint(property, constraints, session)
           end
         end
 
         def index?(index_def)
-          mapped_label.indexes[:property_keys].include?(index_def)
+          mapped_label.indexes[:property_keys].include?([index_def])
         end
 
         # @return [Array{Symbol}] all the labels that this class has
         def mapped_label_names
           self.ancestors.find_all { |a| a.respond_to?(:mapped_label_name) }.map { |a| a.mapped_label_name.to_sym }
         end
 
         # @return [Symbol] the label that this class has which corresponds to a Ruby class
         def mapped_label_name
-          @_label_name || self.to_s.to_sym
+          @_label_name || (self.name.nil? ? object_id.to_s.to_sym : self.name.to_sym)
         end
 
         # @return [Neo4j::Label] the label for this class
         def mapped_label
           Neo4j::Label.create(mapped_label_name)