Title: Wrong shebang set for OS X installation of Jython
Type: Severity: normal
Components: Versions: Jython 2.7
Milestone: Jython 2.7.1
Status: closed Resolution: fixed
Dependencies: Superseder:
Assigned To: stefan.richthofer Nosy List: darjus, stefan.richthofer, zyasoft
Priority: urgent Keywords:

Created on 2017-03-13.23:08:44 by zyasoft, last changed 2017-05-21.00:23:21 by stefan.richthofer.

msg11225 (view) Author: Jim Baker (zyasoft) Date: 2017-03-13.23:08:42
OS X is now failing in certain cases, namely yolk, because of a regression on #1112 For now, this may require patching setuptools for Jython itself, as was done earlier; see #2298

To reproduce (and this should be part of any release testing, as a smoke test):

1. Build an installer (in dist/jython-installer.jar):

$ ant all-jars  # will emit warnings like crazy, mostly around doc tags

2. Run the installer. There are many ways to run this, and they should all be ideally tested. More info on possible installer options:

$ java -jar dist/jython-installer.jar --help

However, the CLI is the easiest way to do any testing - especially since the installer has been very stable, with only pip/setuptools integration being added to it in the last 10 or so years:

$ java -jar dist/jython-installer.jar -s -d ~/jython-2.7.1-test-RC1
Performing silent installation
 10 %
 20 %
 30 %
 40 %
 50 %
 60 %
 70 %
 80 %
Generating start scripts ...
Installing pip and setuptools
 90 %
Collecting setuptools
Collecting pip
Installing collected packages: setuptools, pip
Successfully installed pip-9.0.1 setuptools-28.8.0
 100 %
Congratulations! You successfully installed Jython 2.7.1rc1 to directory /Users/jbaker/jython-2.7.1-test-RC1.

3. OK, let's try it out. First, does pip work?

$ cd ~/jython-2.7.1-test-RC1/
jimbaker:jython-2.7.1-test-RC1 jbaker$ bin/pip install yolk
Collecting yolk
/Users/jbaker/jython-2.7.1-test-RC1/Lib/site-packages/pip/_vendor/requests/packages/urllib3/util/ SNIMissingWarning: An HTTPS request has been made, but the SNI (Subject Name Indication) extension to TLS is not available on this platform. This may cause the server to present an incorrect TLS certificate, which can cause validation failures. You can upgrade to a newer version of Python to solve this. For more information, see
  Using cached yolk-0.4.3.tar.gz
Requirement already satisfied: setuptools in ./Lib/site-packages (from yolk)
Installing collected packages: yolk
  Running install for yolk ... done
Successfully installed yolk-0.4.3

This SNI warning is due to the fact I'm running on Java 7; if you use Java 8, it goes away, and SNI is used (as in fact is tested in our regrtest).

4. Does setuptools work, in conjunction with yolk?

The reason I chose yolk is that it creates a executable in the bin directory for Jython:

$ ls -ls bin/yolk
8 -rwxr-xr-x  1 jbaker  staff  397 Mar 13 16:31 bin/yolk

However, right now it's not working on OS X, because yolk is being interpreted as a **shell script**:
$ bin/yolk
bin/yolk: line 3: __requires__: command not found
Version: ImageMagick 6.9.3-6 Q16 x86_64 2016-02-28
Copyright: Copyright (C) 1999-2016 ImageMagick Studio LLC
... # most output elided but more of the same as the confusing text below!
By default, 'file' is written in the MIFF image format.  To
specify a particular image format, precede the filename with an image
format name and a colon (i.e. ps:image) or specify the image type as
the filename suffix (i.e.  Specify 'file' as '-' for
standard input or output.
import: delegate library support not built-in `' (X11) @ error/import.c/ImportImageCommand/1297.
from: can't read /var/mail/pkg_resources
./yolk: line 9: syntax error near unexpected token `('
./yolk: line 9: `    sys.argv[0] = re.sub(r'(-script\.pyw?|\.exe)?$', '', sys.argv[0])'

This bug is because OS X does not properly support recursive shebangs, as noted in #1112 (and also To fix, instead of a shebang like the following:


We need this:

#!/usr/bin/env /Users/jbaker/jython-2.7.1-test-RC1/bin/jython

With just this small change, yolk will now work:

$ bin/yolk --list
pip 9.0.1 has no metadata
setuptools 28.8.0 has no metadata
wsgiref         - 0.1.2        - active development (/Users/jbaker/jython-2.7.1-test-RC1/Lib)
yolk            - 0.4.3        - active
msg11228 (view) Author: Stefan Richthofer (stefan.richthofer) Date: 2017-03-14.13:33:23
Maybe related to
msg11360 (view) Author: Stefan Richthofer (stefan.richthofer) Date: 2017-05-07.10:48:44
So, in a Jython sprint we investigated this issue and found the regression point. It's actually a regression in setup tools:
(added darjus to nosy for this)

Take a look at the discarded method as_header:
It contained the shebang correction that is vital for OSX.

In Jython-side this commit pulled the regression into Jython:

So, how should we fix it? Restore the relevant code in setuptools?
Or maybe better monkeypatch setuptools from Jython, so we have better control over this aspect, wich might be convenient if launchers change over time etc...
E.g. I suppose this problem would go away if we could introduce LiJy-launch as default launcher:
(It is constrained to OpenJDK's license (GPL with classpath exception) because it inherits from OpenJDK C-code. Don't know what trouble it would make to have a stricter license just for the launcher. The launcher is usually not subject to library binding etc.; Also, I will take a look if I can maybe remove or rewrite the relevant code, or maybe we can ask OpenJDK for permission to use the code snippet in question under PSF2 license.)
msg11362 (view) Author: Jim Baker (zyasoft) Date: 2017-05-07.16:34:31
Agreed that using something like LiJy would make this problem go away, because we would have a real executable as a launcher, much as we see with the Windows launcher. Better yet, it would be direct. But there are both build (need to do this for every platform, although creative use of CPython could help) and licensing problems as pointed out.

If we could "seamlessly" monkeypatch setuptools CommandSpec as necessary, that would give us control for this thorny issue, without having to maintain a Jython-specific patch of setuptools (thereby limiting upgrades of pypa upstream work like pip), while preserving the ability to revise the installer for a specific version of Jython. Maybe we could manage through some suitable cleverness in Again, this only works because CommandSpec is relatively stable... And it is monkeypatching!
msg11376 (view) Author: Stefan Richthofer (stefan.richthofer) Date: 2017-05-18.12:00:39
I think I fixed it. Will push it soon...
msg11377 (view) Author: Jim Baker (zyasoft) Date: 2017-05-18.17:17:08
Stefan, thanks for working on this, and I look forward to seeing and trying out the commit!
msg11378 (view) Author: Stefan Richthofer (stefan.richthofer) Date: 2017-05-18.23:35:22
Fixed as of
msg11381 (view) Author: Jim Baker (zyasoft) Date: 2017-05-19.02:53:23
That is an interesting place to do the monkeypatch! I wonder what further power could be exposed there, given its centrality.
msg11386 (view) Author: Jim Baker (zyasoft) Date: 2017-05-20.02:47:06
Works for me! I think we can safely close, this is a good approach for the time being.
msg11387 (view) Author: Darjus Loktevic (darjus) Date: 2017-05-20.18:39:52
Guys, sorry for this and thanks for the fix.
msg11388 (view) Author: Stefan Richthofer (stefan.richthofer) Date: 2017-05-21.00:23:20
> That is an interesting place to do the monkeypatch! I wonder what further power could be exposed there, given its centrality.

Hmmm, it was the only place I could think of that can guarantee the monkeypatch to be applied before the patched module is used. And at the same time avoids to patch it twice. It puzzles me a bit that the name 'easy_install' never shows up there, which is why I check for 'setuptools.command' ( asserts that actually easy_install is the target).

NP ;)
Date User Action Args
2017-05-21 00:23:21stefan.richthofersetmessages: + msg11388
2017-05-20 18:39:52darjussetmessages: + msg11387
2017-05-20 02:47:06zyasoftsetstatus: pending -> closed
messages: + msg11386
2017-05-19 02:53:23zyasoftsetmessages: + msg11381
2017-05-18 23:35:22stefan.richthofersetstatus: open -> pending
resolution: fixed
messages: + msg11378
2017-05-18 17:17:08zyasoftsetmessages: + msg11377
2017-05-18 12:00:40stefan.richthofersetassignee: stefan.richthofer
messages: + msg11376
2017-05-07 16:34:32zyasoftsetmessages: + msg11362
2017-05-07 10:48:45stefan.richthofersetnosy: + darjus
messages: + msg11360
2017-03-14 13:33:23stefan.richthofersetnosy: + stefan.richthofer
messages: + msg11228
2017-03-13 23:08:44zyasoftcreate