tests/misc/sort-merge-fdlimit: don't assume -R opens /dev/urandom

* tests/misc/sort-merge-fdlimit: This test was written assuming that
-R typically opens /dev/urandom, but that's no longer the case.
Redo test to specify a random source; this resurrects the point of
checking for file descriptor exhaustion.  Also try plain -R, since
that implementation may change in the future too.

diff --git a/tests/misc/sort-merge-fdlimit b/tests/misc/sort-merge-fdlimit
index d1736f50c39d62c8a87a50b2974fbe6026658202..56b85181147745948299852ccbec297d6f3291ed 100755 (executable)
--- a/tests/misc/sort-merge-fdlimit
+++ b/tests/misc/sort-merge-fdlimit
@@ -31,6 +31,7 @@ mkdir in err || framework_failure
 for i in `seq 17`; do
   echo $i >in/$i
 done
+seq 17 >some-data
 
 # When these tests are run inside the automated testing framework, they
 # have one less available file descriptor than when run outside the
@@ -43,11 +44,14 @@ done
    && sort -m --batch-size=16 in/* 2>err/merge-default-err \
    || ! grep "open failed" err/merge-default-err) || fail=1
 
-# If sort opens a file (/dev/urandom) to sort by random hashes of keys,
+# If sort opens a file to sort by random hashes of keys,
 # it needs to consider this file against its limit on open file
-# descriptors.
-(ulimit -n 20 \
-   && sort -mR --batch-size=16 in/* 2>err/merge-random-err \
-   || ! grep "open failed" err/merge-random-err) || fail=1
+# descriptors.  Test once with the default random source
+# and once with an explicit source.
+for randsource in '' --random-source=some-data; do
+  (ulimit -n 20 \
+     && sort -mR $randsource --batch-size=16 in/* 2>err/merge-random-err \
+     || ! grep "open failed" err/merge-random-err) || fail=1
+done
 
 Exit $fail