Finish 3.3.0

.github/workflows/ci.yml

@@ -25,7 +25,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ruby: [2.6, 2.7, '3.0', 3.1, 3.2, ruby-head, jruby]
+        ruby: ['3.0', 3.1, 3.2, ruby-head, jruby]
     steps:
       - name: Clone repository
         uses: actions/checkout@v3

Gemfile

@@ -31,6 +31,6 @@ group :test do
   gem "rake"
   gem "equivalent-xml"
   gem 'fasterer'
-  gem 'simplecov', '~> 0.21',  platforms: :mri
+  gem 'simplecov', '~> 0.22',  platforms: :mri
   gem 'simplecov-lcov', '~> 0.8',  platforms: :mri
 end

README.md

@@ -14,26 +14,28 @@ This is a pure-Ruby library for working with [Resource Description Framework
 
 1. [Features](#features)
 2. [Differences between RDF 1.0 and RDF 1.1](#differences-between-rdf-1-0-and-rdf-1-1)
-3. [Tutorials](#tutorials)
-4. [Command Line](#command-line)
-5. [Examples](#examples)
-6. [Reader/Writer convenience methods](#reader/writer-convenience-methods)
-7. [RDF* (RDFStar)](#rdf*-(rdfstar))
-8. [Documentation](#documentation)
-9. [Dependencies](#dependencies)
-10. [Installation](#installation)
-11. [Download](#download)
-12. [Resources](#resources)
-13. [Mailing List](#mailing-list)
-14. [Authors](#authors)
-15. [Contributors](#contributors)
-16. [Contributing](#contributing)
-17. [License](#license)
+3. [Differences between RDF 1.1 and RDF 1.2](#differences-between-rdf-1-1-and-rdf-1-2)
+4. [Tutorials](#tutorials)
+5. [Command Line](#command-line)
+6. [Examples](#examples)
+7. [Reader/Writer convenience methods](#reader/writer-convenience-methods)
+8. [RDF 1.2](#rdf\_12)
+9. [Documentation](#documentation)
+10. [Dependencies](#dependencies)
+11. [Installation](#installation)
+12. [Download](#download)
+13. [Resources](#resources)
+14. [Mailing List](#mailing-list)
+15. [Authors](#authors)
+16. [Contributors](#contributors)
+17. [Contributing](#contributing)
+18. [License](#license)
 
 ## Features
 
 * 100% pure Ruby with minimal dependencies and no bloat.
 * Fully compatible with [RDF 1.1][] specifications.
+* Provisional support for [RDF 1.2][] specifications.
 * 100% free and unencumbered [public domain](https://unlicense.org/) software.
 * Provides a clean, well-designed RDF object model and related APIs.
 * Supports parsing and serializing [N-Triples][] and [N-Quads][] out of the box, with more
@@ -45,11 +47,10 @@ This is a pure-Ruby library for working with [Resource Description Framework
   not modify any of Ruby's core classes or standard library.
 * Based entirely on Ruby's autoloading, meaning that you can generally make
   use of any one part of the library without needing to load up the rest.
-* Compatible with Ruby Ruby >= 2.4, Rubinius and JRuby 9.0+.
-  * Note, changes in mapping hashes to keyword arguments for Ruby 2.7+ may require that arguments be passed more explicitly, especially when the first argument is a Hash and there are optional keyword arguments. In this case, Hash argument may need to be explicitly included within `{}` and the optional keyword arguments may need to be specified using `**{}` if there are no keyword arguments.
+* Compatible with Ruby Ruby >= 3.0, Rubinius and JRuby 9.0+.
+  * Note, changes in mapping hashes to keyword arguments for Ruby 3+ may require that arguments be passed more explicitly, especially when the first argument is a Hash and there are optional keyword arguments. In this case, Hash argument may need to be explicitly included within `{}` and the optional keyword arguments may need to be specified using `**{}` if there are no keyword arguments.
 * Performs auto-detection of input to select appropriate Reader class if one
   cannot be determined from file characteristics.
-* Provisional support for [RDF*][].
 
 ### HTTP requests
 
@@ -102,6 +103,10 @@ the 1.1 release of RDF.rb:
 
 Notably, {RDF::Queryable#query} and {RDF::Query#execute} are now completely symmetric; this allows an implementation of {RDF::Queryable} to optimize queries using implementation-specific logic, allowing for substantial performance improvements when executing BGP queries.
 
+## Differences between RDF 1.1 and RDF 1.2
+* {RDF::Literal} has an optional `direction` property for directional language-tagged strings.
+* Removes support for legacy `text/plain` (as an alias for `application/n-triples`) and `text/x-nquads` (as an alias for `application/n-quads`)
+
 ## Tutorials
 
 * [Getting data from the Semantic Web using Ruby and RDF.rb](https://semanticweb.org/wiki/Getting_data_from_the_Semantic_Web_%28Ruby%29)
@@ -260,23 +265,24 @@ A separate [SPARQL][SPARQL doc] gem builds on basic BGP support to provide full
     foaf[:name]   #=> RDF::URI("http://xmlns.com/foaf/0.1/name")
     foaf['mbox']  #=> RDF::URI("http://xmlns.com/foaf/0.1/mbox")
 
-## RDF* (RDFStar)
+## RDF 1.2
 
-[RDF.rb][] includes provisional support for [RDF*][] with an N-Triples/N-Quads syntax extension that uses inline statements in the _subject_ or _object_ position.
+[RDF.rb][] includes provisional support for [RDF 1.2][] with an N-Triples/N-Quads syntax for quoted triples in the _subject_ or _object_ position.
+[RDF.rb][] includes provisional support for [RDF 1.2][] directional language-tagged strings, which are literals of type `rdf:dirLangString` having both a `language` and `direction`.
 
 Internally, an `RDF::Statement` is treated as another resource, along with `RDF::URI` and `RDF::Node`, which allows an `RDF::Statement` to have a `#subject` or `#object` which is also an `RDF::Statement`.
 
 **Note: This feature is subject to change or elimination as the standards process progresses.**
 
-### Serializing a Graph containing embedded statements
+### Serializing a Graph containing quoted triples
 
     require 'rdf/ntriples'
     statement = RDF::Statement(RDF::URI('bob'), RDF::Vocab::FOAF.age, RDF::Literal(23))
     graph = RDF::Graph.new << [statement, RDF::URI("ex:certainty"), RDF::Literal(0.9)]
     graph.dump(:ntriples, validate: false)
     # => '<<<bob> <http://xmlns.com/foaf/0.1/age> "23"^^<http://www.w3.org/2001/XMLSchema#integer>>> <ex:certainty> "0.9"^^<http://www.w3.org/2001/XMLSchema#double> .'
 
-### Reading a Graph containing embedded statements
+### Reading a Graph containing quoted triples
 
 By default, the N-Triples reader will reject a document containing a subject resource.
 
@@ -286,13 +292,6 @@ By default, the N-Triples reader will reject a document containing a subject res
     end
     # => RDF::ReaderError
 
-Readers support a boolean valued `rdfstar` option.
-
-    graph = RDF::Graph.new do |graph|
-      RDF::NTriples::Reader.new(nt, rdfstar: true) {|reader| graph << reader}
-    end
-    graph.count #=> 1
-
 ## Documentation
 
 <https://ruby-rdf.github.io/rdf>
@@ -398,16 +397,17 @@ from BNode identity (i.e., they each entail the other)
 
 ## Dependencies
 
-* [Ruby](https://ruby-lang.org/) (>= 2.6)
+* [Ruby](https://ruby-lang.org/) (>= 3.0)
 * [LinkHeader][] (>= 0.0.8)
+* [bcp47_spec][] ( ~> 0.2)
 * Soft dependency on [RestClient][] (>= 2.1)
 
 ## Installation
 
 The recommended installation method is via [RubyGems](https://rubygems.org/).
 To install the latest official release of RDF.rb, do:
 
-    % [sudo] gem install rdf             # Ruby 2.6+
+    % [sudo] gem install rdf             # Ruby 3+
 
 ## Download
 
@@ -481,8 +481,10 @@ This is free and unencumbered public domain software. For more information,
 see <https://unlicense.org/> or the accompanying {file:UNLICENSE} file.
 
 [RDF]:              https://www.w3.org/RDF/
-[N-Triples]:        https://www.w3.org/TR/n-triples/
-[N-Quads]:          https://www.w3.org/TR/n-quads/
+[LinkHeader]:     https://github.com/asplake/link_header
+[bcp47_spec]:   https://github.com/dadah89/bcp47_spec
+[N-Triples]:        https://www.w3.org/TR/rdf-n-triples/
+[N-Quads]:          https://www.w3.org/TR/rdf-n-quads/
 [YARD]:             https://yardoc.org/
 [YARD-GS]:          https://rubydoc.info/docs/yard/file/docs/GettingStarted.md
 [PDD]:              https://unlicense.org/#unlicensing-contributions
@@ -496,6 +498,7 @@ see <https://unlicense.org/> or the accompanying {file:UNLICENSE} file.
 [SPARQL doc]:       https://ruby-rdf.github.io/sparql
 [RDF 1.0]:          https://www.w3.org/TR/2004/REC-rdf-concepts-20040210/
 [RDF 1.1]:          https://www.w3.org/TR/rdf11-concepts/
+[RDF 1.2]:          https://www.w3.org/TR/rdf12-concepts/
 [SPARQL 1.1]:       https://www.w3.org/TR/sparql11-query/
 [RDF.rb]:           https://ruby-rdf.github.io/
 [RDF::DO]:          https://ruby-rdf.github.io/rdf-do
@@ -510,7 +513,6 @@ see <https://unlicense.org/> or the accompanying {file:UNLICENSE} file.
 [RDF::TriX]:        https://ruby-rdf.github.io/rdf-trix
 [RDF::Turtle]:      https://ruby-rdf.github.io/rdf-turtle
 [RDF::Raptor]:      https://ruby-rdf.github.io/rdf-raptor
-[RDF*]:             https://w3c.github.io/rdf-star/rdf-star-cg-spec.html
 [LinkedData]:       https://ruby-rdf.github.io/linkeddata
 [JSON::LD]:         https://ruby-rdf.github.io/json-ld
 [RestClient]:       https://rubygems.org/gems/rest-client

VERSION

@@ -1 +1 @@
-3.2.11
+3.3.0

etc/n-triples.ebnf

@@ -1,6 +1,40 @@
-[1] ntriplesDoc ::= triple? (EOL triple)* EOL?
-[2] triple      ::= subject predicate object '.'
-[3] subject     ::= IRIREF | BLANK_NODE_LABEL
-[4] predicate   ::= IRIREF
-[5] object      ::= IRIREF | BLANK_NODE_LABEL | literal
-[6] literal     ::= STRING_LITERAL_QUOTE ('^^' IRIREF | LANGTAG)?
+ntriplesDoc       ::= triple? (EOL triple)* EOL?
+triple            ::= subject predicate object '.'
+subject           ::= IRIREF | BLANK_NODE_LABEL | quotedTriple
+predicate         ::= IRIREF
+object            ::= IRIREF | BLANK_NODE_LABEL | literal | quotedTriple
+literal           ::= STRING_LITERAL_QUOTE ('^^' IRIREF | LANG_DIR )?
+quotedTriple      ::= '<<' subject predicate object '>>'
+
+@terminals
+
+IRIREF            ::=  '<' ([^#x00-#x20<>"{}|^`\] | UCHAR)* '>'
+BLANK_NODE_LABEL  ::= '_:' ( PN_CHARS_U | [0-9] ) ((PN_CHARS|'.')* PN_CHARS)?
+LANG_DIR          ::= "@" [a-zA-Z]+ ( "-" [a-zA-Z0-9]+ )* ('--' [a-zA-Z]+)?`
+STRING_LITERAL_QUOTE ::= '"' ( [^#x22#x5C#xA#xD] | ECHAR | UCHAR )* '"'
+UCHAR             ::= ( "\u" HEX HEX HEX HEX )
+                    | ( "\U" HEX HEX HEX HEX HEX HEX HEX HEX )
+ECHAR             ::= ("\" [tbnrf"'])
+PN_CHARS_BASE     ::= ([A-Z]
+                    | [a-z]
+                    | [#x00C0-#x00D6]
+                    | [#x00D8-#x00F6]
+                    | [#x00F8-#x02FF]
+                    | [#x0370-#x037D]
+                    | [#x037F-#x1FFF]
+                    | [#x200C-#x200D]
+                    | [#x2070-#x218F]
+                    | [#x2C00-#x2FEF]
+                    | [#x3001-#xD7FF]
+                    | [#xF900-#xFDCF]
+                    | [#xFDF0-#xFFFD]
+                    | [#x10000-#xEFFFF])
+PN_CHARS_U        ::=  PN_CHARS_BASE | '_'
+PN_CHARS          ::= (PN_CHARS_U
+                    | "-"
+                    | [0-9]
+                    | #x00B7
+                    | [#x0300-#x036F]
+                    | [#x203F-#x2040])
+HEX               ::= ([0-9] | [A-F] | [a-f])
+EOL               ::= [#xD#xA]+

lib/rdf/cli.rb

@@ -60,7 +60,7 @@ module RDF
   #         RDF::CLI::Option.new(
   #           symbol: :canonicalize,
   #           on: ["--canonicalize"],
-  #           description: "Canonicalize input/output.") {true},
+  #           description: "Canonicalize URI/literal forms.") {true},
   #         RDF::CLI::Option.new(
   #           symbol: :uri,
   #           on: ["--uri STRING"],

lib/rdf/mixin/enumerable.rb

@@ -83,7 +83,8 @@ def to_a
     #   * `:literal_equality' preserves [term-equality](https://www.w3.org/TR/rdf11-concepts/#dfn-literal-term-equality) for literals. Literals are equal only if their lexical values and datatypes are equal, character by character. Literals may be "inlined" to value-space for efficiency only if `:literal_equality` is `false`.
     #   * `: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.
-    #   * `:rdfstar` supports RDF* where statements may be subjects or objects of other statements.
+    #   * `:quoted_triples` supports RDF 1.2 quoted triples.
+    #   * `:base_direction` supports RDF 1.2 directional language-tagged strings.
     #
     # @param  [Symbol, #to_sym] feature
     # @return [Boolean]
@@ -720,13 +721,33 @@ def enum_graph
     end
     alias_method :enum_graphs, :enum_graph
 
+    ##
+    # Enumerates each statement using its canonical representation.
+    #
+    # @note This is updated by `RDF::Normalize` to also canonicalize blank nodes.
+    #
+    # @return [RDF::Enumerable]
+    def canonicalize
+      this = self
+      Enumerable::Enumerator.new do |yielder|
+        this.send(:each_statement) {|y| yielder << y.canonicalize}
+      end
+    end
+
+    ##
+    # Mutating canonicalization not supported
+    #
+    # @raise NotImplementedError
+    def canonicalize!
+      raise NotImplementedError, "Canonicalizing enumerables not supported"
+    end
+
     ##
     # Returns all RDF statements in `self` as an array.
     #
     # Mixes in `RDF::Enumerable` into the returned object.
     #
     # @return [Array]
-    # @since  0.2.0
     def to_a
       super.extend(RDF::Enumerable)
     end

lib/rdf/mixin/queryable.rb

@@ -140,7 +140,7 @@ def query_execute(query, **options, &block)
     # method in order to provide for storage-specific optimized triple
     # pattern matching.
     #
-    # ## RDFStar (RDF*)
+    # ## RDF-star
     #
     # Statements may have embedded statements as either a subject or object, recursively.
     #

lib/rdf/mixin/writable.rb

@@ -127,8 +127,11 @@ def insert_graph(graph)
     def insert_statements(statements)
       each = statements.respond_to?(:each_statement) ? :each_statement : :each
       statements.__send__(each) do |statement|
-        if statement.embedded? && respond_to?(:supports?) && !supports?(:rdfstar)
-          raise ArgumentError, "Wriable does not support embedded statements"
+        if statement.embedded? && respond_to?(:supports?) && !supports?(:quoted_triples)
+          raise ArgumentError, "Writable does not support quoted triples"
+        end
+        if statement.object && statement.object.literal? && statement.object.direction? && !supports?(:base_direction)
+          raise ArgumentError, "Writable does not support directional languaged-tagged strings"
         end
         insert_statement(statement)
       end

lib/rdf/model/dataset.rb

@@ -104,7 +104,7 @@ def isolation_level
     # @private
     # @see RDF::Enumerable#supports?
     def supports?(feature)
-      return true if %i(graph_name rdfstar).include?(feature)
+      return true if %i(graph_name quoted_triples).include?(feature)
       super
     end
 

lib/rdf/model/graph.rb

@@ -305,8 +305,11 @@ def query_pattern(pattern, **options, &block)
     # @private
     # @see RDF::Mutable#insert
     def insert_statement(statement)
-      if statement.embedded? && !@data.supports?(:rdfstar)
-        raise ArgumentError, "Graph does not support embedded statements"
+      if statement.embedded? && !@data.supports?(:quoted_triples)
+        raise ArgumentError, "Graph does not support quoted triples"
+      end
+      if statement.object && statement.object.literal? && statement.object.direction? &&  !@data.supports?(:base_direction)
+        raise ArgumentError, "Graph does not support directional languaged-tagged strings"
       end
       statement = statement.dup
       statement.graph_name = graph_name