Ensure generated SPARQL queries are syntactically valid

glowtables/table.py

@@ -160,7 +160,7 @@ class Table:
                 yield SparqlVariable(f"{prefix}{i}")
 
         subject = SparqlVariable("subject")
-        columns = ", ".join(f"?{field.id}" for field in self.fields)
+        columns = " ".join(f"?{field.id}" for field in self.fields)
         statements = "\n    ".join(
             field.sparql(subject, SparqlVariable(field.id), new_var(field.id).__next__)
             for field in self.fields

glowtables/tests/table_test.py

@@ -20,7 +20,7 @@ import rdflib
 from glowtables.table import Language, LiteralField, Table
 
 
-def test_single_literal() -> None:
+def test_single_literal(rdflib_sparql) -> None:
     name_field = LiteralField(
         "display_name",
         {Language("en"): "Name"},
@@ -41,8 +41,10 @@ def test_single_literal() -> None:
         """
     )
 
+    rdflib_sparql.query(table.sparql())
 
-def test_two_literals() -> None:
+
+def test_two_literals(rdflib_sparql) -> None:
     name_field = LiteralField(
         "display_name",
         {Language("en"): "Name"},
@@ -60,7 +62,7 @@ def test_two_literals() -> None:
 
     assert table.sparql() == textwrap.dedent(
         """
-        SELECT ?display_name, ?frequency
+        SELECT ?display_name ?frequency
         WHERE {
             ?subject <http://example.org/type> <http://example.org/CPU>.
             ?subject <http://example.org/display-name> ?display_name.
@@ -69,8 +71,10 @@ def test_two_literals() -> None:
         """
     )
 
+    rdflib_sparql.query(table.sparql())
 
-def test_default_value() -> None:
+
+def test_default_value(rdflib_sparql) -> None:
     name_field = LiteralField(
         "display_name",
         {Language("en"): "Name"},
@@ -92,6 +96,8 @@ def test_default_value() -> None:
         """
     )
 
+    rdflib_sparql.query(table.sparql())
+
 
 def test_field_id_subject() -> None:
     name_field = LiteralField(