Added a test for toRDF() without a baseIRI.

Relates to #113

test/rdf-without-baseiri.js

@@ -0,0 +1,47 @@
+/*
+ * Test generation of RDF without a base IRI.
+ */
+
+const fs = require('fs');
+const path = require('path');
+
+const chai = require('chai');
+const phyx = require('../src');
+
+const expect = chai.expect;
+
+/**
+ * Test whether conversion of Phyx files to an OWL ontology in RDF works even without a baseIRI.
+ * This was an issue in https://github.com/phyloref/phyx.js/issues/113
+ */
+
+describe('PhyxWrapper', function () {
+  describe('toRDF() without baseIRI', function () {
+    const examples = fs.readdirSync(path.resolve(__dirname, './examples/correct'))
+      .filter(filename => filename.endsWith('.json'));
+
+    examples.forEach((example) => {
+      const basename = path.resolve(__dirname, './examples/correct', path.parse(example).name);
+      const jsonFilename = `${basename}.json`;
+
+      let json;
+
+      describe(`Test file '${example}'`, function () {
+        it('should be loadable', function () {
+          json = JSON.parse(fs.readFileSync(jsonFilename));
+          expect(json).to.be.an('object');
+        });
+
+        it('should be convertible to n-Quads without a baseIRI', function () {
+          this.timeout(10000);
+          return new phyx.PhyxWrapper(json).toRDF('', path.resolve(__dirname, 'examples', 'correct'))
+            .then((nquads) => {
+              expect(nquads).to.not.be.empty;
+              expect(nquads).to.contain('http://ontology.phyloref.org/phyloref.owl#Phyloreference');
+              expect(nquads).to.contain('http://ontology.phyloref.org/phyloref.owl#newick_expression');
+            });
+        });
+      });
+    });
+  });
+});