Improve hack to allow blank node predicates in Turtle

rubensworks · Jun 20, 2019 · 34b3ef4 · 34b3ef4
1 parent 247ec8d
commit 34b3ef4
Show file tree

Hide file tree

Showing 2 changed files with 31 additions and 10 deletions.
diff --git a/lib/GeneralizedN3StreamParser.ts b/lib/GeneralizedN3StreamParser.ts
@@ -1,6 +1,20 @@
 import {Parser} from "n3";
 import {Transform} from "stream";
 
+// Temporarily set format to text/n3 to allow blank node predicates (needed by JSON-LD tests)
+const readPredicateOld = Parser.prototype._readPredicate;
+// tslint:disable-next-line:only-arrow-functions
+Parser.prototype._readPredicate = function(token: any) {
+  if (this.allowBlankNodePredicates) {
+    this._n3Mode = true;
+  }
+  const ret = readPredicateOld.call(this, token);
+  if (this.allowBlankNodePredicates) {
+    this._n3Mode = false;
+  }
+  return ret;
+};
+
 export class GeneralizedN3StreamParser extends Transform {
 
   constructor(options: any) {
@@ -10,9 +24,7 @@ export class GeneralizedN3StreamParser extends Transform {
 
     // Set up parser
     const parser: any = new Parser(options);
-
-    // Set to format to text/n3 to allow blank node predicates (needed by JSON-LD tests)
-    parser._n3Mode = true;
+    parser.allowBlankNodePredicates = true;
 
     let onData: any;
     let onEnd: any;

diff --git a/test/Util-test.ts b/test/Util-test.ts
@@ -1,4 +1,4 @@
-import {literal, namedNode, quad} from "@rdfjs/data-model";
+import {blankNode, literal, namedNode, quad} from "@rdfjs/data-model";
 import {existsSync, mkdirSync, readFileSync} from "fs";
 import "isomorphic-fetch";
 import "jest-rdf";
@@ -174,21 +174,30 @@ describe('Util', () => {
         ]);
     });
 
+    it('should parse text/turtle streams with blank node predicates', async () => {
+      expect(await arrayifyStream(Util.parseRdfRaw('text/turtle', 'http://example.org/',
+        streamifyString('<a> _:b <c>.'))))
+        .toEqualRdfQuadArray([
+          quad(namedNode('http://example.org/a'), blankNode('b'),
+            namedNode('http://example.org/c')),
+        ]);
+    });
+
     it('should parse application/n-triples streams', async () => {
       expect(await arrayifyStream(Util.parseRdfRaw('application/n-triples', 'http://example.org/',
-        streamifyString('<a> <b> <c>.'))))
+        streamifyString('<http://ex.org/a> <http://ex.org/b> <http://ex.org/c>.'))))
         .toEqualRdfQuadArray([
-          quad(namedNode('http://example.org/a'), namedNode('http://example.org/b'),
-            namedNode('http://example.org/c')),
+          quad(namedNode('http://ex.org/a'), namedNode('http://ex.org/b'),
+            namedNode('http://ex.org/c')),
         ]);
     });
 
     it('should parse application/n-quads streams', async () => {
       expect(await arrayifyStream(Util.parseRdfRaw('application/n-quads', 'http://example.org/',
-        streamifyString('<a> <b> <c> <d>.'))))
+        streamifyString('<http://ex.org/a> <http://ex.org/b> <http://ex.org/c> <http://ex.org/d>.'))))
         .toEqualRdfQuadArray([
-          quad(namedNode('http://example.org/a'), namedNode('http://example.org/b'),
-            namedNode('http://example.org/c'), namedNode('http://example.org/d')),
+          quad(namedNode('http://ex.org/a'), namedNode('http://ex.org/b'),
+            namedNode('http://ex.org/c'), namedNode('http://ex.org/d')),
         ]);
     });