Implement operator/bgp instead of using RDF::Query directly, set cont…

…ext = false.

Don't set context = false for graphs with a nil context, as this was modifying behavior of other packages that include sparql..

VERSION

@@ -1 +1 @@
-0.0.8
+0.0.9

lib/sparql/algebra/extensions.rb

@@ -177,55 +177,6 @@ def concise_bounded_description(*terms, &block)
 end
 
 class RDF::Query
-  alias_method :initialize_without_expression, :initialize
-  ##
-  # Initializes a new basic graph pattern query.
-  #
-  # @overload initialize(patterns = [], options = {})
-  #   @param  [Array<RDF::Query::Pattern>] patterns
-  #     ...
-  #   @param  [Hash{Symbol => Object}] options
-  #     any additional keyword options
-  #   @option options [RDF::Query::Solutions] :solutions (Solutions.new)
-  #   @option options [RDF::Term, RDF::Query::Variable, Boolean] :context (false)
-  #     Default context for matching against queryable.
-  #     Named queries either match against a specifically named
-  #     contexts if the name is an RDF::Term or bound RDF::Query::Variable.
-  #     Names that are against unbound variables match either detault
-  #     or named contexts.
-  # The name of `false' will only match against the default context.
-  #   @yield  [query]
-  #   @yieldparam  [RDF::Query] query
-  #   @yieldreturn [void] ignored
-  #
-  # @overload initialize(patterns, options = {})
-  #   @param  [Hash{Object => Object}] patterns
-  #     ...
-  #   @param  [Hash{Symbol => Object}] options
-  #     any additional keyword options
-  #   @option options [RDF::Query::Solutions] :solutions (Solutions.new)
-  #   @option options [RDF::Term, RDF::Query::Variable, Boolean] :context (false)
-  #     Default context for matching against queryable.
-  #     Named queries either match against a specifically named
-  #     contexts if the name is an RDF::Term or bound RDF::Query::Variable.
-  #     Names that are against unbound variables match either detault
-  #     or named contexts.
-  #   @yield  [query]
-  #   @yieldparam  [RDF::Query] query
-  #   @yieldreturn [void] ignored
-  def initialize(*patterns, &block)
-    initialize_without_expression(*patterns) do
-      self.context = false if self.context.nil?
-
-      if block_given?
-        case block.arity
-          when 0 then instance_eval(&block)
-          else block.call(self)
-        end
-      end
-    end
-  end
-
   # Equivalence for Queries:
   #   Same Patterns
   #   Same Context

lib/sparql/algebra/operator.rb

@@ -45,6 +45,7 @@ class Operator
     # Query operators
     autoload :Ask,                'sparql/algebra/operator/ask'
     autoload :Base,               'sparql/algebra/operator/base'
+    autoload :BGP,                'sparql/algebra/operator/bgp'
     autoload :Construct,          'sparql/algebra/operator/construct'
     autoload :Dataset,            'sparql/algebra/operator/dataset'
     autoload :Describe,           'sparql/algebra/operator/describe'
@@ -112,7 +113,7 @@ def self.for(name, arity = nil)
         # Query forms
         when :ask         then Ask
         when :base        then Base
-        when :bgp         then RDF::Query
+        when :bgp         then BGP
         when :construct   then Construct
         when :describe    then Describe
         when :distinct    then Distinct

lib/sparql/algebra/operator/bgp.rb

@@ -0,0 +1,26 @@
+module SPARQL; module Algebra
+  class Operator
+    ##
+    # The SPARQL GraphPattern `bgp` operator.
+    #
+    # Query with `context` set to false.
+    #
+    # @example
+    #   (prefix ((: <http://example/>))
+    #     (bgp (triple ?s ?p ?o)))
+    #
+    # @see http://www.w3.org/TR/rdf-sparql-query/#sparqlAlgebra
+    class BGP < Operator
+      NAME = [:bgp]
+      ##
+      # A `graph` is an RDF::Query with a context.
+      #
+      # @param [RDF::URI, RDF::Query::Variable] context
+      # @param [RDF::Query] bgp
+      # @return [RDF::Query]
+      def self.new(*patterns)
+        RDF::Query.new(*patterns, :context => false)
+      end
+    end # BGP
+  end # Operator
+end; end # SPARQL::Algebra

spec/query_spec.rb

@@ -830,7 +830,7 @@
       query.execute(queryable)
     end
 
-    it "raises error when loading into non-mutable queryable", :focus => true do
+    it "raises error when loading into non-mutable queryable" do
       queryable = RDF::Repository.new
       query = SPARQL::Algebra::Expression.parse(%q((dataset (<data-g1.ttl>) (bgp))))
       lambda {query.execute(queryable)}.should raise_error(TypeError)