D5543: histedit: crashing with a more useful error message on empty defaultrev

[rdamazio (Rodrigo Damazio Bovendorp)]

rdamazio created this revision.
Herald added a reviewer: durin42.
Herald added a subscriber: mercurial-devel.
Herald added a reviewer: hg-reviewers.

REVISION SUMMARY
  Before this, `hg --config histedit.defaultrev= histedit` would crash with
  File "destutil.py", line 385, in desthistedit
  
    if revs:
  
  UnboundLocalError: local variable 'revs' referenced before assignment

REPOSITORY
  rHG Mercurial

REVISION DETAIL
  https://phab.mercurial-scm.org/D5543

AFFECTED FILES
  mercurial/destutil.py
  tests/test-histedit-arguments.t

CHANGE DETAILS

diff --git a/tests/test-histedit-arguments.t b/tests/test-histedit-arguments.t
--- a/tests/test-histedit-arguments.t
+++ b/tests/test-histedit-arguments.t
@@ -112,6 +112,13 @@
   > pick 08d98a8350f3 4 five
   > EOF
 
+Test invalid config default
+---------------------------
+
+  $ hg histedit --config "histedit.defaultrev="
+  abort: config option histedit.defaultrev can't be empty
+  [255]
+
 Run on a revision not descendants of the initial parent
 --------------------------------------------------------------------
 
diff --git a/mercurial/destutil.py b/mercurial/destutil.py
--- a/mercurial/destutil.py
+++ b/mercurial/destutil.py
@@ -381,6 +381,8 @@
         revs = stack.getstack(repo)
     elif default:
         revs = scmutil.revrange(repo, [default])
+    else:
+        raise error.Abort('config option histedit.defaultrev can\'t be empty')
 
     if revs:
         # Take the first revision of the revset as the root



To: rdamazio, durin42, #hg-reviewers
Cc: mercurial-devel