fix: show output on failed assert

Author: d-perl

bec_ipython_client/tests/client_tests/test_bec_client.py

@@ -58,11 +58,11 @@ def test_bec_entry_point_globals_and_post_startup(tmpdir):  # , capfd):
     # all_completions('bec.') should return a list of strings, one of which is 'bec.device_manager'
     # we can therefore limit the output to lines that start with '[' and end with ']'
     output_lines = [out for out in output.split("\n") if out.startswith("[") and out.endswith("]")]
-    assert "bec.device_manager" in output_lines[0]
+    assert "bec.device_manager" in output_lines[0], output
     assert (
         "BECIPythonClient" not in output_lines[1]
-    )  # just to ensure something we don't want is really not there
-    assert "test_gui_id" in output
+    ), output  # just to ensure something we don't want is really not there
+    assert "test_gui_id" in output, output
 
 
 def test_bec_load_hli_tab_completion(tmpdir):