Fix issue #936 HAVING clause with variable comparison not correctly evaluated

rdflib/plugins/sparql/algebra.py

@@ -569,7 +569,7 @@ def translateAggregates(
                 v.expr = traverse(v.expr, functools.partial(_aggs, A=A))
 
     # having clause
-    if traverse(q.having, _hasAggregate, complete=False):
+    if traverse(q.having, _hasAggregate, complete=True):
         q.having = traverse(q.having, _sample)
         traverse(q.having, functools.partial(_aggs, A=A))
 

test/test_having.py

@@ -0,0 +1,35 @@
+from rdflib import Graph
+
+g = Graph()
+
+data = """
+<urn:a> <urn:p> 1 .
+<urn:b> <urn:p> 3 .
+<urn:c> <urn:q> 1 .
+"""
+g.parse(data=data, format="turtle")
+
+
+def test_group_by():
+    query = "SELECT ?p" "WHERE { ?s ?p ?o } " "GROUP BY ?p"
+    qres = g.query(query)
+
+    assert len(qres) == 2
+
+
+def test_having_aggregate_eq_literal():
+    query = (
+        "SELECT ?p (avg(?o) as ?a) "
+        "WHERE { ?s ?p ?o } "
+        "GROUP BY ?p HAVING (avg(?o) = 2 )"
+    )
+    qres = g.query(query)
+
+    assert len(qres) == 1
+
+
+def test_having_primary_expression_var_neq_iri():
+    query = "SELECT ?p " "WHERE { ?s ?p ?o } " "GROUP BY ?p HAVING (?p != <urn:foo> )"
+    qres = g.query(query)
+
+    assert len(qres) == 2