From 3f4b96906571aaca007f6939e01e31c520da956d Mon Sep 17 00:00:00 2001
From: Val Lorentz <progval+opdb@progval.net>
Date: Sun, 21 May 2023 17:37:47 +0200
Subject: [PATCH] Ensure generated SPARQL queries are syntactically valid

---
 glowtables/table.py            |  2 +-
 glowtables/tests/table_test.py | 14 ++++++++++----
 2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/glowtables/table.py b/glowtables/table.py
index 905386d..e0d800e 100644
--- a/glowtables/table.py
+++ b/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
diff --git a/glowtables/tests/table_test.py b/glowtables/tests/table_test.py
index f43d00e..faa8105 100644
--- a/glowtables/tests/table_test.py
+++ b/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(