# HG changeset patch
# User Siddharth Agarwal <sid0@fb.com>
# Date 2016-02-12 19:44:35
# Node ID 2a71d948319988b999fdfa8ce83c895ce59de598
# Parent  88e309a0c13366384b152ef7cbfde2d4802d6322

hook: for python hook exceptions, add note to run with --traceback

Just like with ImportErrors, it isn't obvious that --traceback will produce
helpful debugging output here.

diff --git a/mercurial/hook.py b/mercurial/hook.py
--- a/mercurial/hook.py
+++ b/mercurial/hook.py
@@ -106,6 +106,8 @@ def _pythonhook(ui, repo, name, hname, f
                            '%s\n') % (hname, exc))
         if throw:
             raise
+        if not ui.tracebackflag:
+            ui.warn(_('(run with --traceback for stack trace)\n'))
         ui.traceback()
         return True, True
     finally:
diff --git a/tests/test-hook.t b/tests/test-hook.t
--- a/tests/test-hook.t
+++ b/tests/test-hook.t
@@ -541,6 +541,7 @@ post- python hooks that fail to *run* do
   searching for changes
   no changes found
   error: post-pull.broken hook raised an exception: unsupported operand type(s) for +: 'int' and 'dict'
+  (run with --traceback for stack trace)
 
 but post- python hooks that fail to *load* do
   $ echo '[hooks]' > .hg/hgrc