Fix setting of source_url in context for loop

rdflib_jsonld/context.py

@@ -192,7 +192,7 @@ def load(self, source, base=None):
             self._read_source(source, source_url)
 
     def _prep_sources(self, base, inputs, sources, referenced_contexts=None,
-            source_url=None):
+            in_source_url=None):
         referenced_contexts = referenced_contexts or set()
         for source in inputs:
             if isinstance(source, basestring):
@@ -203,6 +203,8 @@ def _prep_sources(self, base, inputs, sources, referenced_contexts=None,
                 source = source_to_json(source_url)
                 if CONTEXT not in source:
                     raise errors.INVALID_REMOTE_CONTEXT
+            else:
+                source_url = in_source_url
 
             if isinstance(source, dict):
                 if CONTEXT in source:

test/test_context.py

@@ -132,7 +132,19 @@ def test_loading_contexts():
 def test_use_base_in_local_context():
     ctx = Context({'@base': "/local"})
     assert ctx.base == '/local'
-    # Ignore @base in remote contexts
+
+def test_override_base():
+    ctx = Context(base="http://example.org/app/data/item",
+            source={'@base': "http://example.org/"})
+    assert ctx.base == "http://example.org/"
+
+def test_set_null_base():
+    ctx = Context(base="http://example.org/app/data/item",
+            source={'@base': None})
+    assert ctx.base is None
+    assert ctx.resolve_iri("../other") == "../other"
+
+def test_ignore_base_remote_context():
     ctx_url = "http://example.org/remote-base.jsonld"
     SOURCES[ctx_url] = {'@context': {'@base': "/remote"}}
     ctx = Context(ctx_url)