Don't parse quoted triples when validating.

Author: gkellogg

lib/rdf/mixin/enumerable.rb

@@ -84,7 +84,7 @@ def to_a
     #   * `:validity` allows a concrete Enumerable implementation to indicate that it does or does not support valididty checking. By default implementations are assumed to support validity checking.
     #   * `:skolemize` supports [Skolemization](https://www.w3.org/wiki/BnodeSkolemization) of an `Enumerable`. Implementations supporting this feature must implement a `#skolemize` method, taking a base URI used for minting URIs for BNodes as stable identifiers and a `#deskolemize` method, also taking a base URI used for turning URIs having that prefix back into the same BNodes which were originally skolemized.
     #   * `:rdf_full` supports RDF 1.2 Full profile, including support for embedded Triple Terms.
-    #   * `:quoted_triples` supports RDF-star quoted triples.
+    #   * `:quoted_triples` supports RDF-star quoted triples. (DEPRECATED)
     #   * `:base_direction` supports RDF 1.2 directional language-tagged strings.
     #
     # @param  [Symbol, #to_sym] feature

lib/rdf/ntriples/reader.rb

@@ -259,9 +259,9 @@ def read_tripleTerm
 
     ##
     # @return [RDF::Statement]
-    # @deprecated Quoted triples are now deprecated
+    # @deprecated Quoted triples are now deprecated (not supported when validating)
     def read_quotedTriple
-      if @options[:rdfstar] && !match(TT_START) && match(QT_START)
+      if @options[:rdfstar] && !match(TT_START) && match(QT_START) && !validate?
         warn "[DEPRECATION] RDF-star quoted triples are deprecated and will be removed in a future version.\n" +
              "Called from #{Gem.location_of_caller.join(':')}"
         subject   = read_uriref || read_node || read_quotedTriple || fail_subject

lib/rdf/repository.rb

@@ -273,7 +273,7 @@ def supports?(feature)
         when :literal_equality then true
         when :atomic_write     then true
         when :rdf_full         then true
-        when :quoted_triples   then true
+        when :quoted_triples   then true  # DEPRECATED
         when :base_direction   then true
         when :snapshots        then true
         else false