syntax error in jruby unix startup

I noticed this is still an issue in 1.6RC2 - any thoughts on when it will be resolved?

This was introduced by https://github.com/jruby/jruby/commit/fba86378c53a19a3974d19e89177e95df507d529

Which is a response to JRUBY-3695.

Can't really do anything about this one since it was intended to fix an issue on CentOS. Chris: can you do a bit of research and see if there's a way we can resolve this bug AND keep JRUBY-3695 fixed?

Sure, seems like a fun one to track down, and I have access to Suse and Solaris boxes, and I can spin up a CentOS VM on Parallels.

Are there tests for these types of issues? I'm still getting my head around TDD, and I don't know how you would create a test for something like this.

Chris: We have a test/test_command_line_options.rb that shows how to test an external JRuby launching. Something like that, explicitly loading jruby.bash, would be a good way to ensure the script continues to work.

We've experienced the same problem on OSX 10.8 (see https://trac.macports.org/ticket/36036).
Our fix escapes the slash: '\/', which is legal according to:
https://developer.apple.com/library/mac/#documentation/Darwin/Reference/ManPages/man1/expr.1.html
and
https://developer.apple.com/library/mac/#documentation/Darwin/Reference/ManPages/man7/re_format.7.html

I don't know if that's portable, but I verified that it works on CentOS 6.2.
But JRUBY-3695 isn't reproducible on CentOS 6.2 anyway.

Escaping the slash may indeed be fine. Investigating.

I tried to reproduce, and then when I couldn't I realized your report points out this is new behavior on Mountain Lion. I am on Lion.

For most people we recommend installing our native executable (gem install jruby-launcher) which avoids a lot of these little issues with bash (I think). I don't have a problem making the change you recommend, but we need some confirmation across bash/expr/OS versions that it won't break other platforms.

Can you show me exactly how you symlink JRuby to reproduce this, so I can at least confirm that case doesn't break on Lion with your change?

The symlink is:
lrwxr-xr-x 1 root admin 37 18 Sep 23:53 /opt/local/bin/jruby -> /opt/local/share/java/jruby/bin/jruby

I can confirm that escaping the slash works on Snow Leopard (10.6), Lion (10.7) and Mountain Lion (10.8).

Forgot to resolve this.

commit b1fec0dd242ee473094cbba32dc7a553f24dbb0b
Author: Charles Oliver Nutter <headius@headius.com>
Date:   Fri Sep 21 09:10:13 2012 -0500

    Try a new technique for finding jruby home that avoids 'expr'.

diff --git a/bin/jruby.bash b/bin/jruby.bash
old mode 100644
new mode 100755
index a1f3e11..0d79b0b
--- a/bin/jruby.bash
+++ b/bin/jruby.bash
@@ -25,24 +25,22 @@ if [ -z "$JAVA_VM" ]; then
   JAVA_VM=-client
 fi
 
-## resolve links - $0 may be a link to  home
-PRG=$0
-progname=`basename "$0"`
-
-while [ -h "$PRG" ] ; do
-  ls=`ls -ld "$PRG"`
-  link=`expr "$ls" : '.*-> \(.*\)$'`
-  if expr "$link" : '.*/.*' > /dev/null; then
-    if expr "$link" : '/' > /dev/null; then
-      PRG="$link"
-    else
-      PRG="`dirname ${PRG}`/${link}"
-    fi
-  else
-    PRG="`dirname $PRG`/$link"
-  fi
+# get the absolute path of the executable
+SELF_PATH=$(cd -P -- "$(dirname -- "$0")" && pwd -P) && SELF_PATH=$SELF_PATH/$(basename -- "$0")
+
+# resolve symlinks
+while [ -h $SELF_PATH ]; do
+    # 1) cd to directory of the symlink
+    # 2) cd to the directory of where the symlink points
+    # 3) get the pwd
+    # 4) append the basename
+    DIR=$(dirname -- "$SELF_PATH")
+    SYM=$(readlink $SELF_PATH)
+    SELF_PATH=$(cd $DIR && cd $(dirname -- "$SYM") && pwd)/$(basename -- "$SYM")
 done
 
+PRG=$SELF_PATH
+
 JRUBY_HOME_1=`dirname "$PRG"`           # the ./bin dir
 if [ "$JRUBY_HOME_1" = '.' ] ; then
   cwd=`pwd`