add a test for redis using NoOpTracerProvider (open-telemetry#1559)

instrumentation/opentelemetry-instrumentation-redis/tests/test_redis.py

@@ -15,6 +15,7 @@
 
 import redis
 
+from opentelemetry import trace
 from opentelemetry.instrumentation.redis import RedisInstrumentor
 from opentelemetry.test.test_base import TestBase
 from opentelemetry.trace import SpanKind
@@ -146,3 +147,16 @@ def request_hook(span, conn, args, kwargs):
 
         span = spans[0]
         self.assertEqual(span.attributes.get(custom_attribute_name), "GET")
+
+    def test_no_op_tracer_provider(self):
+        RedisInstrumentor().uninstrument()
+        tracer_provider = trace.NoOpTracerProvider
+        RedisInstrumentor().instrument(tracer_provider=tracer_provider)
+
+        redis_client = redis.Redis()
+
+        with mock.patch.object(redis_client, "connection"):
+            redis_client.get("key")
+
+        spans = self.memory_exporter.get_finished_spans()
+        self.assertEqual(len(spans), 0)