tests: sort: ensure --batch-size=(rlimit+1) fails

* tests/sort/sort-merge-fdlimit.sh: Add test case.
https://github.com/coreutils/coreutils/pull/182

diff --git a/tests/sort/sort-merge-fdlimit.sh b/tests/sort/sort-merge-fdlimit.sh
index bb9c2c0816daa49a9f692ca40a030d92094da396..54e790d066223e319030f57d1c2aadd47f42de41 100755 (executable)
--- a/tests/sort/sort-merge-fdlimit.sh
+++ b/tests/sort/sort-merge-fdlimit.sh
@@ -34,12 +34,15 @@ seq 17 >some-data
 # inside the ATF, then the same test with batch size b+1 may pass outside
 # the ATF but fail inside it.
 
+(ulimit -n 19 && touch ulimit-worked &&
+ returns_ 2 sort --batch-size=20 /dev/null) || fail=1
+rm ulimit-worked || skip_ 'cannot modify open file descriptor limit'
+
 # The default batch size (nmerge) is 16.
 (ulimit -n 19 && touch ulimit-worked \
    && sort -m --batch-size=16 in/* 2>err/merge-default-err \
    || ! grep "open failed" err/merge-default-err) || fail=1
-
-test -f ulimit-worked || skip_ 'cannot modify open file descriptor limit'
+rm ulimit-worked || skip_ 'cannot modify open file descriptor limit'
 
 # If sort opens a file to sort by random hashes of keys,
 # it needs to consider this file against its limit on open file