--- a/service/mqtt_to_rdf/inference_test.py	Mon Sep 06 17:03:19 2021 -0700
+++ b/service/mqtt_to_rdf/inference_test.py	Mon Sep 06 18:06:11 2021 -0700
@@ -1,14 +1,16 @@
 """
 also see https://github.com/w3c/N3/tree/master/tests/N3Tests
 """
+from collections import defaultdict
 from decimal import Decimal
 from typing import cast
 import unittest
 
 from rdflib import RDF, BNode, ConjunctiveGraph, Graph, Literal, Namespace
+from rdflib.graph import ReadOnlyGraphAggregate
 from rdflib.parser import StringInputSource
 
-from inference import Inference
+from inference import Inference, Lhs
 from rdflib_debug_patches import patchBnodeCounter, patchSlimReprs
 
 patchSlimReprs()
@@ -283,3 +285,29 @@
     #     inf = makeInferenceWithRules("{ :a :b (:e0 :e1 :e2 :e3) . } => { :new :stmt :here } .")
     #     implied = inf.infer(N3(":a :b (:e0 :e1 :e2 :e3) ."))
     #     self.assertGraphEqual(implied, N3(":new :stmt :here ."))
+
+
+def fakeStats():
+    return defaultdict(lambda: 0)
+
+class TestLhsFindCandidateBindings(WithGraphEqual):
+
+    def testBnodeMatchesStmt(self):
+        l = Lhs(N3("[] :a :b ."))
+        ws = ReadOnlyGraphAggregate([N3("[] :a :b .")])
+        cands = list(l.findCandidateBindings(ws, fakeStats()))
+        self.assertEqual(len(cands), 1)
+
+    def testVarMatchesStmt(self):
+        l = Lhs(N3("?x :a :b ."))
+        ws = ReadOnlyGraphAggregate([N3("[] :a :b .")])
+        cands = list(l.findCandidateBindings(ws, fakeStats()))
+        self.assertEqual(len(cands), 1)
+
+    def testListsOnlyMatchEachOther(self):
+        l = Lhs(N3(":a :b (:e0 :e1) ."))
+        ws = ReadOnlyGraphAggregate([N3(":a :b (:e0 :e1) .")])
+        stats = fakeStats()
+        cands = list(l.findCandidateBindings(ws, stats))
+        self.assertLess(stats['permCountFailingVerify'], 20)
+        self.fail(str(cands))
\ No newline at end of file