NoOpTracerProvider test case for httpx instrumentation

Author: dgoscn

instrumentation/opentelemetry-instrumentation-httpx/tests/test_httpx_integration.py

@@ -1292,6 +1292,26 @@ def test_basic_multiple(self):
         self.perform_request(self.URL, client=self.client2)
         self.assert_span(num_spans=2)
 
+    async def test_no_op_tracer_provider(self):
+        HTTPXClientInstrumentor().uninstrument()
+        HTTPXClientInstrumentor().instrument(
+            tracer_provider=trace.NoOpTracerProvider()
+        )
+        async with httpx.AsyncClient() as client:
+            await client.get("http://test.com")
+        spans = self.memory_exporter.get_finished_spans()
+        self.assertEqual(len(spans), 0)
+
+    def test_no_op_tracer_provider_sync(self):
+        HTTPXClientInstrumentor().uninstrument()
+        HTTPXClientInstrumentor().instrument(
+            tracer_provider=trace.NoOpTracerProvider()
+        )
+        with httpx.Client() as client:
+            client.get("http://test.com")
+        spans = self.memory_exporter.get_finished_spans()
+        self.assertEqual(len(spans), 0)
+
     def test_async_response_hook_does_nothing_if_not_coroutine(self):
         HTTPXClientInstrumentor().instrument(
             tracer_provider=self.tracer_provider,