Issue 166 in SPARQLWrapper solved

CONTRIBUTORS

@@ -45,6 +45,7 @@ Niklas Lindström
 Pierre-Antoine Champin
 Phil Dawes
 Phillip Pearson
+Pritish Wadhwa
 Ron Alford
 Remi Chateauneu
 Sidnei da Silva

rdflib/plugins/sparql/algebra.py

@@ -422,15 +422,24 @@ def _findVars(x, res):
     """
     Find all variables in a tree
     """
+    seenVars = set()
     if isinstance(x, Variable):
-        res.add(x)
+        if x not in seenVars:
+            res.append(x)
+            seenVars.add(x)
     if isinstance(x, CompValue):
         if x.name == "Bind":
-            res.add(x.var)
+            if x.var not in seenVars:
+                res.append(x.var)
+                seenVars.add(x.var)
             return x  # stop recursion and finding vars in the expr
         elif x.name == "SubSelect":
             if x.projection:
-                res.update(v.var or v.evar for v in x.projection)
+                tempList = [v.var or v.evar for v in x.projection]
+                for a in tempList:
+                    if a not in seenVars:
+                        res.append(a)
+                        seenVars.add(a)
             return x
 
 
@@ -548,7 +557,7 @@ def translate(q):
     q.where = traverse(q.where, visitPost=translatePath)
 
     # TODO: Var scope test
-    VS = set()
+    VS = list()
     traverse(q.where, functools.partial(_findVars, res=VS))
 
     # all query types have a where part

test/test_issues/test_issue166.py

@@ -0,0 +1,15 @@
+import pytest
+
+import rdflib
+from rdflib import Graph
+
+
+def test_issue_166() -> None:
+    g = Graph()
+    query = "SELECT * { ?a ?b ?c } LIMIT 10"
+    qres = g.query(query)
+    assert qres.vars == [
+        rdflib.term.Variable('a'),
+        rdflib.term.Variable('b'),
+        rdflib.term.Variable('c'),
+    ]