Change the script-generation logic to not use pkg_resources at run

time. Rather, we generate in-line logic that pkg_resources would provide.
This means that apps that don't actually use pkg_resources themselves
don't end up running it and we don't need to implicitly include the
setuptools egg in the script path.  Of course, if an application does
use setuptools, then setuptools will be one of it's requirements and
will be included in the path.


git-svn-id: http://svn.zope.org/repos/main/zc.buildout/trunk@68521 62d5b8a3-27da-0310-9561-8e5933582275

eggrecipe/src/zc/recipe/egg/README.txt

@@ -82,12 +82,11 @@ We can also run the py_demo script.  Here we'll just print out
 the bits if the path added to reflect the eggs:
 
     >>> print system(os.path.join(sample_buildout, 'bin', 'py_demo'),
-    ... """for p in sys.path[:3]:
+    ... """for p in sys.path[:2]:
     ...        print p
     ... """).replace('>>> ', '').replace('... ', ''),
     ... # doctest: +ELLIPSIS
     <BLANKLINE>
-    /usr/local/python/2.3.5/lib/python/setuptools-0.6b2-py2.3.egg
     /tmp/tmpcy8MvGbuildout-tests/eggs/demo-0.2-py2.3.egg
     /tmp/tmpcy8MvGbuildout-tests/eggs/demoneeded-1.0-py2.3.egg
     <BLANKLINE>

src/zc/buildout/egglinker.py

@@ -23,6 +23,7 @@ $Id$
 """
 
 # XXX needs doctest
+# XXX need to deal with extras
 
 import os
 import sys
@@ -33,7 +34,6 @@ def distributions(reqs, eggss):
     env = pkg_resources.Environment(eggss)
     ws = pkg_resources.WorkingSet()
     reqs = [pkg_resources.Requirement.parse(r) for r in reqs]
-    reqs.append(pkg_resources.Requirement.parse('setuptools'))
     return ws.resolve(reqs, env=env)
 
 def path(reqs, eggss):
@@ -65,7 +65,7 @@ def scripts(reqs, dest, eggss, scripts=None):
 
                 sname = os.path.join(dest, sname)
                 generated.append(sname)
-                _script(dist, name, path, sname)
+                _script(dist, 'console_scripts', name, path, sname)
 
             name = 'py_'+dist.project_name
             if scripts is not None:
@@ -80,12 +80,15 @@ def scripts(reqs, dest, eggss, scripts=None):
 
     return generated
 
-def _script(dist, name, path, dest):
+def _script(dist, group, name, path, dest):
+    entry_point = dist.get_entry_info(group, name)
     open(dest, 'w').write(script_template % dict(
         python = sys.executable,
         path = path,
         project = dist.project_name,
         name = name,
+        module_name = entry_point.module_name,
+        attrs = entry_point.attrs,
         ))
     try:
         os.chmod(dest, 0755)
@@ -100,12 +103,19 @@ sys.path[0:0] = [
   '%(path)s'
   ]
 
-from pkg_resources import load_entry_point
 
-sys.exit(
-   load_entry_point('%(project)s', 'console_scripts', '%(name)s')()
-)
+module = __import__(%(module_name)r, globals(),globals(), ['__name__'])
+attrs = %(attrs)r
 
+entry = module
+for attr in attrs:
+    try:
+        entry = getattr(entry, attr)
+    except AttributeError:
+        raise ImportError("%%r has no %%r attribute" %% (module, attrs))
+
+if __name__ == '__main__':
+    entry()
 '''