fixes Issue 1003, with tests

2 files changed, 31 insertions, 0 deletions

diff --git a/rdflib/plugins/serializers/turtle.py b/rdflib/plugins/serializers/turtle.py
index 1c58ba1b..6d31c579 100644
--- a/rdflib/plugins/serializers/turtle.py
+++ b/rdflib/plugins/serializers/turtle.py
@@ -291,6 +291,9 @@ class TurtleSerializer(RecursiveSerializer):
     def startDocument(self):
         self._started = True
         ns_list = sorted(self.namespaces.items())
+
+        if self.base:
+            self.write(self.indent() + '@base <%s> .\n' % self.base)
         for prefix, uri in ns_list:
             self.write(self.indent() + '@prefix %s: <%s> .\n' % (prefix, uri))
         if ns_list and self._spacious:
diff --git a/test/test_issue1003.py b/test/test_issue1003.py
new file mode 100644
index 00000000..34a194a6
--- /dev/null
+++ b/test/test_issue1003.py
@@ -0,0 +1,28 @@
+from rdflib import Graph, Literal, Namespace, RDF, URIRef
+from rdflib.namespace import SKOS, DCTERMS
+
+g = Graph()
+
+base = Namespace("http://example.org/")
+
+title = Literal("Title", lang="en")
+description = Literal("Test Description", lang="en")
+creator = URIRef("https://creator.com")
+cs = URIRef("")
+
+g.add((cs, RDF.type, SKOS.ConceptScheme))
+g.add((cs, DCTERMS.creator, creator))
+g.add((cs, DCTERMS.source, URIRef("nick")))
+
+# Bind a few prefix, namespace pairs for more readable output
+g.bind("dct", DCTERMS)
+g.bind("skos", SKOS)
+
+# this one should not have @base in the output
+assert "@base" not in g.serialize(format='turtle').decode("utf-8")
+# this one should have @base in the output
+assert "@base" in g.serialize(format='turtle', base=base).decode("utf-8")
+
+# and same for N3 (same serializer used)
+assert "@base" not in g.serialize(format='n3').decode("utf-8")
+assert "@base" in g.serialize(format='n3', base=base).decode("utf-8")