--- a/hgext/narrow/narrowcommands.py	Sun Dec 16 00:21:54 2018 -0500
+++ b/hgext/narrow/narrowcommands.py	Fri Nov 23 22:12:04 2018 -0800
@@ -365,15 +365,13 @@
     """
     opts = pycompat.byteskwargs(opts)
     if repository.NARROW_REQUIREMENT not in repo.requirements:
-        ui.warn(_('The narrow command is only supported on respositories cloned'
-                  ' with --narrow.\n'))
-        return 1
+        raise error.Abort(_('the narrow command is only supported on '
+                            'respositories cloned with --narrow'))
 
     # Before supporting, decide whether it "hg tracked --clear" should mean
     # tracking no paths or all paths.
     if opts['clear']:
-        ui.warn(_('The --clear option is not yet supported.\n'))
-        return 1
+        raise error.Abort(_('the --clear option is not yet supported'))
 
     # import rules from a file
     newrules = opts.get('import_rules')

--- a/tests/test-narrow-trackedcmd.t	Sun Dec 16 00:21:54 2018 -0500
+++ b/tests/test-narrow-trackedcmd.t	Fri Nov 23 22:12:04 2018 -0800
@@ -196,8 +196,8 @@
   X path:widest
 
   $ hg tracked --import-rules specs --clear
-  The --clear option is not yet supported.
-  [1]
+  abort: the --clear option is not yet supported
+  [255]
 
 Testing with passing a out of wdir file