Add :pn_local_validation option and fix pn_local regex

CHANGELOG.md

@@ -21,6 +21,8 @@ Elixir v1.15 or later, where this issue has been resolved.
 - Capability to add custom content on the Turtle/TriG encoders with the `:content` option.
 - Option `:line_prefix` on Turtle/TriG encoder for a function defining custom line prefixes.
 - Option `:indent_width` on Turtle/TriG encoder to customize the indentation width.
+- Option `:pn_local_validation` on Turtle/TriG encoder for controlling IRI validation 
+  when encoding as a prefixed name.
 - `RDF.Dataset.update_all_graphs/2` to apply a function on all graphs of a dataset.
 - `RDF.Dataset.named_graphs/1` to get a list of all named graphs of a dataset.
 - `RDF.Dataset.graph_names/1` to get a list of all graph names of a dataset.
@@ -50,6 +52,9 @@ Elixir v1.15 or later, where this issue has been resolved.
 
 - The `RDF.Turtle.Encoder` was not falling back to using `RDF.default_prefixes/0` when
   the encoded graph had prefixes which were removed afterwards.
+- Fixed the `RDF.Turtle.Encoder` validation to ensure IRIs with permissible characters, 
+  such as hyphens, can be correctly encoded as prefixed names. Previously, the validation 
+  was overly strict, preventing some valid IRIs from being encoded as prefixed names.
 - `RDF.NTriples.Encoder` and `RDF.NQuads.Encoder` could not stream quoted RDF-star 
   triples could as iodata.
 

lib/rdf/serializations/turtle_trig/encoder.ex

@@ -59,6 +59,17 @@ defmodule RDF.TurtleTriG.Encoder do
     - `:indent`: Allows to specify the number of spaces the output should be indented.
     - `:indent_width`: Allows to specify the number of spaces that should be used for
       indentations (default: 4).
+    - `:pn_local_validation`: This option controls how IRIs are validated the check
+       whether they can encoded as a prefixed name. Available settings are:
+      - `:fast` (default): Provides a quick and efficient validation that covers most
+        common cases. It does not handle every possible valid scenario, focusing instead
+        on typical structures encountered in prefixed names.
+      - `:none`: Disables validation entirely. Use this mode if you are confident that
+        all your IRIs are already compliant with prefixed name requirements, allowing you
+        to bypass validation checks for increased performance.
+      - Note: Currently, a `:strict` mode, which would provide comprehensive validation
+        conforming strictly to the Turtle specification, is not implemented.
+        Contributions for implementing this mode are welcome.
     """
   end
 
@@ -359,7 +370,7 @@ defmodule RDF.TurtleTriG.Encoder do
 
   defp term(%IRI{} = iri, state, _) do
     based_name(iri, state.base) ||
-      prefixed_name(iri, state.prefixes) ||
+      prefixed_name(iri, state.prefixes, state.pn_local_validation) ||
       ["<", to_string(iri), ">"]
   end
 
@@ -444,16 +455,28 @@ defmodule RDF.TurtleTriG.Encoder do
     ]
   end
 
-  def prefixed_name(iri, prefixes) do
+  def prefixed_name(iri, prefixes, pn_local_validation \\ :fast) do
     case PrefixMap.prefix_name_pair(prefixes, iri) do
-      {prefix, name} -> if valid_pn_local?(name), do: [prefix, ":", name]
+      {prefix, name} -> if valid_pn_local?(name, pn_local_validation), do: [prefix, ":", name]
       _ -> nil
     end
   end
 
-  defp valid_pn_local?(name) do
-    String.match?(name, ~r/^([[:alpha:]]|[[:digit:]]|_|:)*$/u)
-  end
+  @doc """
+  Validates if the local part of a prefixed name is valid according to the Turtle grammar for a `PN_LOCAL`.
+  """
+  def valid_pn_local?(pn_local, pn_local_validation \\ :fast)
+
+  def valid_pn_local?(_pn_local, :none), do: true
+  def valid_pn_local?("", _), do: true
+
+  @fast_pn_local_regex ~r/
+     ^[\p{L}\p{Nd}_:%]
+      [\p{L}\p{Nd}\p{M}\p{Pc}_.:~\-%]*
+      [\p{L}\p{Nd}_:]?$
+    /ux
+
+  def valid_pn_local?(pn_local, :fast), do: String.match?(pn_local, @fast_pn_local_regex)
 
   defp quoted(string) do
     if String.contains?(string, ["\n", "\r"]) do

lib/rdf/serializations/turtle_trig/encoder/state.ex

@@ -6,8 +6,9 @@ defmodule RDF.TurtleTriG.Encoder.State do
     :data,
     :graph,
     :base,
-    :prefixes,
     :implicit_base,
+    :prefixes,
+    :pn_local_validation,
     :single_triple_lines,
     :line_prefix,
     :base_indent,
@@ -43,6 +44,7 @@ defmodule RDF.TurtleTriG.Encoder.State do
       base: base,
       implicit_base: Keyword.get(opts, :implicit_base),
       prefixes: prefixes,
+      pn_local_validation: Keyword.get(opts, :pn_local_validation, :fast),
       base_indent: Keyword.get(opts, :indent),
       indent_step: opts |> Keyword.get(:indent_width, @default_indent_width) |> indent_string(),
       line_prefix: line_prefix,

test/unit/serializations/turtle_trig_encoder_test.exs

@@ -13,7 +13,7 @@ defmodule RDF.TurtleTriG.EncoderTest do
 
   defvocab EX, base_iri: "http://example.org/#", terms: [], strict: false
 
-  describe "prefixed_name/2" do
+  describe "prefixed_name/3 (fast)" do
     setup do
       {:ok,
        prefixes:
@@ -26,6 +26,10 @@ defmodule RDF.TurtleTriG.EncoderTest do
     test "hash iri with existing prefix", %{prefixes: prefixes} do
       assert TurtleTriG.Encoder.prefixed_name(EX.foo(), prefixes) |> IO.iodata_to_binary() ==
                "ex:foo"
+
+      assert TurtleTriG.Encoder.prefixed_name(~I<http://example.org/#foo-bar>, prefixes)
+             |> IO.iodata_to_binary() ==
+               "ex:foo-bar"
     end
 
     test "hash iri namespace without name", %{prefixes: prefixes} do