Merged -r105475:105584...

Merged -r105475:105584 svn+ssh://reinout@svn.zope.org/repos/main/zc.buildout/branches/reinout_distribute_upgrade_check
This is the fix for an infinite recursion when updating Distribute.
Solved by using the available setuptools/distribute for easy_installing the Distribute tgz instead of searching for it, which tries to install, which searches...

CHANGES.txt

@@ -4,7 +4,13 @@ Change History
 1.4.3 (?)
 =========
 
+Bugs fixed:
 
+- Using pre-detected setuptools version for easy_installing tgz files.  This
+  prevents a recursion error when easy_installing an upgraded "distribute"
+  tgz.  Note that setuptools did not have this recursion problem solely
+  because it was packaged as an ``.egg``, which does not have to go through
+  the easy_install step.
 
 
 1.4.2 (2009-11-01)

src/zc/buildout/easy_install.py

@@ -299,10 +299,7 @@ class Installer:
 
         tmp = tempfile.mkdtemp(dir=dest)
         try:
-            path = self._get_dist(
-                self._constrain(pkg_resources.Requirement.parse('setuptools')),
-                ws, False,
-                )[0].location
+            path = setuptools_loc
 
             args = ('-c', _easy_install_cmd, '-mUNxd', _safe_arg(tmp))
             if self._always_unzip:

src/zc/buildout/easy_install.txt

@@ -1208,7 +1208,6 @@ Now, if we install demo, and extdemo:
     GET 200 /demo-0.2-py2.4.egg
     GET 404 /index/demoneeded/
     GET 200 /demoneeded-1.1.zip
-    GET 404 /index/setuptools/
 
     >>> zc.buildout.easy_install.build(
     ...   'extdemo', dest,
@@ -1251,7 +1250,6 @@ Now when we install the distributions:
     GET 404 /index/demo/
     GET 200 /index/
     GET 404 /index/demoneeded/
-    GET 404 /index/setuptools/
 
     >>> zc.buildout.easy_install.build(
     ...   'extdemo', dest,

src/zc/buildout/tests.py

@@ -2921,7 +2921,7 @@ def test_suite():
 
         doctest.DocFileSuite(
             'easy_install.txt', 'downloadcache.txt', 'dependencylinks.txt',
-            'allowhosts.txt', 'unzip.txt',
+            'allowhosts.txt', 'unzip.txt', 'upgrading_distribute.txt',
             setUp=easy_install_SetUp,
             tearDown=zc.buildout.testing.buildoutTearDown,
             checker=renormalizing.RENormalizing([

src/zc/buildout/upgrading_distribute.txt

+Installing setuptools/distribute
+--------------------------------
+
+Some initial test setup:
+
+    >>> import sys
+    >>> import zc.buildout.easy_install
+    >>> dest = tmpdir('sample-install')
+
+Setuptools (0.6something) is packaged as an ``.egg``.  So when installing it,
+the egg is downloaded and used.  Distribute is packaged as a tarball, which
+makes an easy_install call necessary.  In older versions of buildout, the
+``_call_easy_install()`` method would call ``_get_dist()`` to get hold of the
+setuptools path for calling easy_install.  When an updated "distribute" was
+found, this would try an install again, leading to an infinite recursion.
+
+The solution is to just use the setuptools location found at import time, like
+happens with the buildout and setuptools location that is inserted in scripts'
+paths.
+
+We test this corner case by patching the ``_get_dist()`` call:
+
+    >>> def mock_get_dist(requirement, ws, always_unzip):
+    ...     raise RuntimeError("We should not get called")
+
+When installing setuptools itself, we expect the "Getting dist" message not to
+be printed.  We call ``_call_easy_install()`` directly and get an error
+because of a non-existing tarball, but that's the OK for this corner case
+test: we only want to test that ``_get_dist()`` isn't getting called:
+
+    >>> installer = zc.buildout.easy_install.Installer(
+    ...     dest=dest,
+    ...     links=[link_server],
+    ...     index=link_server+'index/',
+    ...     executable=sys.executable,
+    ...     always_unzip=True)
+    >>> installer._get_dist = mock_get_dist
+    >>> installer._call_easy_install('setuptools', None, dest, 
+    ...                              'nonexisting.tgz')
+    Traceback (most recent call last):
+    ...
+    UserError: Couldn't install: nonexisting.tgz