diff --git a/tests/test-extdiff b/tests/test-extdiff
--- a/tests/test-extdiff
+++ b/tests/test-extdiff
@@ -24,7 +24,7 @@ hg ci -d '0 0' -mtest1
 echo b >> a
 hg ci -d '1 0' -mtest2
 
-# should diff cloned files directly 
+# should diff cloned files directly
 hg falabala -r 0:1
 
 # test diff during merge
@@ -34,7 +34,7 @@ hg add c
 hg ci -m "new branch" -d '1 0'
 hg update -C 1
 hg merge tip
-# should diff cloned file against wc file 
+# should diff cloned file against wc file
 hg falabala > out || echo "diff-like tools yield a non-zero exit code"
 # cleanup the output since the wc is a tmp directory
 sed  's:\(.* \).*\(\/test-extdiff\):\1[tmp]\2:' out