# HG changeset patch
# User Sushil khanchi <sushilkhanchi97@gmail.com>
# Date 1576842450 -19800
# Node ID abefd37c6afa7954cdfb2186eeff44f75c424090
# Parent  a3f692bcbbf48d009d565706c4d14eb520e849f4
evolve: add test to demonstrate a bug when active topic is empty

Added test shows that when current active topic is empty and we try
to run `hg up`, it fails with an error. It's because this case is not
correctly handled when we find a destination to update (when topics
are in play)

Next patch will fix this.

diff -r a3f692bcbbf4 -r abefd37c6afa tests/test-topic-dest.t
--- a/tests/test-topic-dest.t	Tue Dec 10 21:03:51 2019 +0100
+++ b/tests/test-topic-dest.t	Fri Dec 20 17:17:30 2019 +0530
@@ -500,3 +500,17 @@
   pick 38eea8439aee 14 arthur
   pick 411315c48bdc 15 pompadour
   #  p, pick = use commit
+
+  $ cd ..
+
+destination check: when active topic is empty
+
+  $ hg init emptytopic
+  $ cd emptytopic
+  $ echo a > a
+  $ hg ci -Am "added a"
+  adding a
+  $ hg topic foo
+  marked working directory as topic: foo
+  $ hg up 2>&1 | grep "AssertionError"
+  AssertionError: any branch has at least one head