From 16e5bc2ce61e8475af5c15bf68313dba96ced178 Mon Sep 17 00:00:00 2001
From: Gregg Kellogg <gregg@greggkellogg.net>
Date: Fri, 5 Jan 2024 15:55:19 -0800
Subject: [PATCH] Properly unescaep PN_LOCAL_ESC.

---
 lib/rdf/turtle/freebase_reader.rb |  8 +++++++
 lib/rdf/turtle/reader.rb          |  9 +++++++-
 spec/freebase_spec.rb             | 36 +++++++++++++++++++++++++++++++
 spec/reader_spec.rb               | 36 +++++++++++++++++++++++++++++++
 spec/terminals_spec.rb            | 21 +++++++-----------
 5 files changed, 96 insertions(+), 14 deletions(-)

diff --git a/lib/rdf/turtle/freebase_reader.rb b/lib/rdf/turtle/freebase_reader.rb
index ce353be..4b81e9b 100644
--- a/lib/rdf/turtle/freebase_reader.rb
+++ b/lib/rdf/turtle/freebase_reader.rb
@@ -64,6 +64,14 @@ def read_pname(**options)
         end
         pfx_iri = prefix(ns)
         raise RDF::ReaderError.new("ERROR [line #{lineno}] prefix #{ns.inspect} is not defined", lineno: lineno) unless pfx_iri
+
+        # Unescape PN_LOCAL_ESC
+        suffix = suffix.gsub(PN_LOCAL_ESC) {|esc| esc[1]} if
+          suffix.match?(PN_LOCAL_ESC)
+
+        # Remove any redundant leading hash from suffix
+        suffix = suffix.sub(/^\#/, "") if pfx_iri.to_s.index("#")
+
         uri = RDF::URI(pfx_iri + suffix)
         uri.validate!     if validate?
         uri
diff --git a/lib/rdf/turtle/reader.rb b/lib/rdf/turtle/reader.rb
index dd801cb..7278a8a 100644
--- a/lib/rdf/turtle/reader.rb
+++ b/lib/rdf/turtle/reader.rb
@@ -227,7 +227,14 @@ def pname(prefix, suffix)
         error("undefined prefix", production: :pname, token: prefix)
         ''
       end
-      suffix = suffix.to_s.sub(/^\#/, "") if base.index("#")
+
+      # Unescape PN_LOCAL_ESC
+      suffix = suffix.gsub(PN_LOCAL_ESC) {|esc| esc[1]} if
+        suffix.match?(PN_LOCAL_ESC)
+
+      # Remove any redundant leading hash from suffix
+      suffix = suffix.sub(/^\#/, "") if base.index("#")
+
       debug("pname", depth: options[:depth]) {"base: '#{base}', suffix: '#{suffix}'"}
       process_iri(base + suffix.to_s)
     end
diff --git a/spec/freebase_spec.rb b/spec/freebase_spec.rb
index 525bd1c..bd419c8 100644
--- a/spec/freebase_spec.rb
+++ b/spec/freebase_spec.rb
@@ -83,6 +83,42 @@
       g = RDF::Graph.new << subject
       expect(g).to be_equivalent_graph("@prefix foo: <http://example/bar#> ." + input, logger: @logger)
     end
+
+    context "PN_LOCAL" do
+      {
+        "p:_a": "<http://a.example/_a>", # PN_CHARS_U
+        "p::": "<http://a.example/:>", # PN_LOCAL
+        "p:0": "<http://a.example/0>", # PN_LOCAL
+        "p:%B7": "<http://a.example/%B7>", # PN_LOCAL
+        "p:a.b": "<http://a.example/a.b>", # PN_LOCAL
+        
+        "p:\\_underscore": "<http://a.example/_underscore>", # PN_LOCAL_ESC
+        "p:\\~tilda": "<http://a.example/~tilda>", # PN_LOCAL_ESC
+        "p:\\.dot": "<http://a.example/.dot>", # PN_LOCAL_ESC
+        "p:\\-dash": "<http://a.example/-dash>", # PN_LOCAL_ESC
+        "p:\\!exclamation": "<http://a.example/!exclamation>", # PN_LOCAL_ESC
+        "p:\\$dollar": "<http://a.example/$dollar>", # PN_LOCAL_ESC
+        "p:\\&amper": "<http://a.example/&amper>", # PN_LOCAL_ESC
+        "p:\\'squote": "<http://a.example/'squote>", # PN_LOCAL_ESC
+        "p:\\(paren\\)": "<http://a.example/(paren)>", # PN_LOCAL_ESC
+        "p:\\*star": "<http://a.example/*star>", # PN_LOCAL_ESC
+        "p:\\+plus": "<http://a.example/+plus>", # PN_LOCAL_ESC
+        "p:\\,comma": "<http://a.example/,comma>", # PN_LOCAL_ESC
+        "p:\\;semi": "<http://a.example/;semi>", # PN_LOCAL_ESC
+        "p:\\=equal": "<http://a.example/=equal>", # PN_LOCAL_ESC
+        "p:\\/slash": "<http://a.example//slash>", # PN_LOCAL_ESC
+        "p:\\?question": "<http://a.example/?question>", # PN_LOCAL_ESC
+        "p:\\#numbersign": "<http://a.example/#numbersign>", # PN_LOCAL_ESC
+        "p:\\@ampersand": "<http://a.example/@ampersand>", # PN_LOCAL_ESC
+        "p:\\%percent": "<http://a.example/%percent>", # PN_LOCAL_ESC
+      }.each do |pn, iri|
+        it pn do
+          ttl = %(@prefix p: <http://a.example/> .\n p:s p:p #{pn} .)
+          nt = %(<http://a.example/s> <http://a.example/p> #{iri} .)
+          expect(parse(ttl, validate: false)).to be_equivalent_graph(nt, logger: @logger)
+        end
+      end
+    end
   end
 
   describe "with simple sample data" do
diff --git a/spec/reader_spec.rb b/spec/reader_spec.rb
index 7df1921..2b0561a 100644
--- a/spec/reader_spec.rb
+++ b/spec/reader_spec.rb
@@ -489,6 +489,42 @@
           nil => "http://test/"})
       end
 
+      context "PN_LOCAL" do
+        {
+          "p:_a": "<http://a.example/_a>", # PN_CHARS_U
+          "p::": "<http://a.example/:>", # PN_LOCAL
+          "p:0": "<http://a.example/0>", # PN_LOCAL
+          "p:%B7": "<http://a.example/%B7>", # PN_LOCAL
+          "p:a.b": "<http://a.example/a.b>", # PN_LOCAL
+          
+          "p:\\_underscore": "<http://a.example/_underscore>", # PN_LOCAL_ESC
+          "p:\\~tilda": "<http://a.example/~tilda>", # PN_LOCAL_ESC
+          "p:\\.dot": "<http://a.example/.dot>", # PN_LOCAL_ESC
+          "p:\\-dash": "<http://a.example/-dash>", # PN_LOCAL_ESC
+          "p:\\!exclamation": "<http://a.example/!exclamation>", # PN_LOCAL_ESC
+          "p:\\$dollar": "<http://a.example/$dollar>", # PN_LOCAL_ESC
+          "p:\\&amper": "<http://a.example/&amper>", # PN_LOCAL_ESC
+          "p:\\'squote": "<http://a.example/'squote>", # PN_LOCAL_ESC
+          "p:\\(paren\\)": "<http://a.example/(paren)>", # PN_LOCAL_ESC
+          "p:\\*star": "<http://a.example/*star>", # PN_LOCAL_ESC
+          "p:\\+plus": "<http://a.example/+plus>", # PN_LOCAL_ESC
+          "p:\\,comma": "<http://a.example/,comma>", # PN_LOCAL_ESC
+          "p:\\;semi": "<http://a.example/;semi>", # PN_LOCAL_ESC
+          "p:\\=equal": "<http://a.example/=equal>", # PN_LOCAL_ESC
+          "p:\\/slash": "<http://a.example//slash>", # PN_LOCAL_ESC
+          "p:\\?question": "<http://a.example/?question>", # PN_LOCAL_ESC
+          "p:\\#numbersign": "<http://a.example/#numbersign>", # PN_LOCAL_ESC
+          "p:\\@ampersand": "<http://a.example/@ampersand>", # PN_LOCAL_ESC
+          "p:\\%percent": "<http://a.example/%percent>", # PN_LOCAL_ESC
+        }.each do |pn, iri|
+          it pn do
+            ttl = %(PREFIX p: <http://a.example/>\n p:s p:p #{pn} .)
+            nt = %(<http://a.example/s> <http://a.example/p> #{iri} .)
+            expect(parse(ttl, validate: false)).to be_equivalent_graph(nt, logger: @logger)
+          end
+        end
+      end
+
       {
         "@prefix foo: <http://foo/bar#> ." => [true, true],
         "@PrEfIx foo: <http://foo/bar#> ." => [false, true],
diff --git a/spec/terminals_spec.rb b/spec/terminals_spec.rb
index 3cc08c4..65c9d17 100644
--- a/spec/terminals_spec.rb
+++ b/spec/terminals_spec.rb
@@ -44,21 +44,16 @@
       ! # $ % & ' ( ) * + , - . / 0 1 2 3 4 5 6 7 8 9 : / < = ? @
       A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
       _ a b c d e f g h i j k l m n o p q r s t u v w x y z ~
-      ab\\u00E9xy ab\xC3\xA9xy>
-      \\u03B1:a \xCE\xB1:a
-      a\\u003Ab a\x3Ab
-      \\U00010000 \xF0\x90\x80\x80
-      \\U000EFFFF \xF3\xAF\xBF\xBF
+      ab\\u00E9xy
+      \\u03B1:a
+      a\\u003Ab
+      \\U00010000
+      \\U000EFFFF
     ).each do |string|
       it "matches <scheme:#{string.inspect}>" do
-        begin
-          string = "<scheme:#{string}>"
-          string.force_encoding(Encoding::UTF_8)
-          expect(string).to match(RDF::Turtle::Terminals::IRIREF)
-        rescue RSpec::Expectations::ExpectationNotMetError
-          pending "Escapes in IRIs"
-          fail
-        end
+        string = "<scheme:#{string}>"
+        string.force_encoding(Encoding::UTF_8)
+        expect(string).to match(RDF::Turtle::Terminals::IRIREF)
       end
     end
   end