wait-on-file: properly wait on any files and symlink

This make the utility more useful, for example to wait on a lock file.
We also add an explicit -L check since the lock are "weird" symlink.

Differential Revision: https://phab.mercurial-scm.org/D12617

tests/testlib/wait-on-file

@@ -1,39 +1,39
 #!/bin/sh
 #
 # wait up to TIMEOUT seconds until a WAIT_ON_FILE is created.
 #
 # In addition, this script can create CREATE_FILE once it is ready to wait.
 
 if [ $# -lt 2 ] || [ $# -gt 3 ]; then
     echo $#
     echo "USAGE: $0 TIMEOUT WAIT_ON_FILE [CREATE_FILE]"
 fi
 
 timer="$1"
 
 # Scale the timeout to match the sleep steps below, i.e. 1/0.02.
 timer=$(( 50 * $timer ))
 # If the test timeout have been extended, also scale the timer relative
 # to the normal timing.
 if [ "$HGTEST_TIMEOUT_DEFAULT" -lt "$HGTEST_TIMEOUT" ]; then
     timer=$(( ( $timer * $HGTEST_TIMEOUT) / $HGTEST_TIMEOUT_DEFAULT ))
 fi
 
 wait_on="$2"
 create=""
 if [ $# -eq 3 ]; then
     create="$3"
 fi
 
 if [ -n "$create" ]; then
     touch "$create"
     create=""
 fi
-while [ "$timer" -gt 0 ] && [ ! -f "$wait_on" ]; do
+while [ "$timer" -gt 0 ] && !([ -e "$wait_on" ] || [ -L "$wait_on" ]) ; do
     timer=$(( $timer - 1))
     sleep 0.02
 done
 if [ "$timer" -le 0 ]; then
     echo "file not created after $1 seconds: $wait_on" >&2
     exit 1
 fi