Do not print traceback warning text if debug is not a settable parameter

2 files changed, 12 insertions, 1 deletions

diff --git a/cmd2/cmd2.py b/cmd2/cmd2.py
index c0246705..19bdc244 100755
--- a/cmd2/cmd2.py
+++ b/cmd2/cmd2.py
@@ -689,7 +689,7 @@ class Cmd(cmd.Cmd):
         if apply_style:
             final_msg = ansi.style_error(final_msg)
 
-        if not self.debug:
+        if not self.debug and 'debug' in self.settable:
             warning = "\nTo enable full traceback, run the following command: 'set debug true'"
             final_msg += ansi.style_warning(warning)
 
diff --git a/tests/test_cmd2.py b/tests/test_cmd2.py
index 6cab69d6..a856c1d6 100755
--- a/tests/test_cmd2.py
+++ b/tests/test_cmd2.py
@@ -670,6 +670,17 @@ now: True
     out, err = run_cmd(base_app, 'edit')
     assert err[0].startswith('Traceback (most recent call last):')
 
+def test_debug_not_settable(base_app):
+    # Set debug to False and make it unsettable
+    base_app.debug = False
+    del base_app.settable['debug']
+
+    # Cause an exception
+    out, err = run_cmd(base_app, 'bad "quote')
+
+    # Since debug is unsettable, the user will not be given the option to enable a full traceback
+    assert err == ['Invalid syntax: No closing quotation']
+
 def test_edit_file(base_app, request, monkeypatch):
     # Set a fake editor just to make sure we have one.  We aren't really going to call it due to the mock
     base_app.editor = 'fooedit'