From 8f9bbb7022903435b36ec0a92c0fe4501e346c48 Mon Sep 17 00:00:00 2001
From: Vincent Pelletier <vincent@nexedi.com>
Date: Mon, 20 Feb 2012 17:59:50 +0100
Subject: [RFC 1/2] Allow extending more than once sections extending other
 sections.

---
 src/zc/buildout/buildout.py |    1 +
 src/zc/buildout/tests.py    |   46 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 47 insertions(+), 0 deletions(-)

diff --git a/src/zc/buildout/buildout.py b/src/zc/buildout/buildout.py
index c733a26..0efb522 100644
--- a/src/zc/buildout/buildout.py
+++ b/src/zc/buildout/buildout.py
@@ -1197,6 +1197,7 @@ class Options(UserDict.DictMixin):
                 result.update(self._do_extend_raw(iname, raw, doing))
 
             result.update(data)
+            data.update(result)
             return result
         finally:
             assert doing.pop() == name
diff --git a/src/zc/buildout/tests.py b/src/zc/buildout/tests.py
index 9bab789..5508068 100644
--- a/src/zc/buildout/tests.py
+++ b/src/zc/buildout/tests.py
@@ -3587,6 +3587,52 @@ def increment_on_command_line():
       recipe='zc.buildout:debug'
     """
 
+def bug_605017_reuse_extending_section():
+    r"""
+    >>> write('buildout.cfg', '''
+    ... [buildout]
+    ... parts = myfiles
+    ...   myfiles2
+    ...
+    ... [debug]
+    ... recipe = zc.buildout:debug
+    ...
+    ... [with_file1]
+    ... <= debug
+    ... file1 = ${:path}/file1
+    ... color = red
+    ...
+    ... [with_file2]
+    ... <= debug
+    ... file2 = ${:path}/file2
+    ... color = blue
+    ...
+    ... [myfiles]
+    ... <= with_file1
+    ...    with_file2
+    ... path = mydata
+    ...
+    ... [myfiles2]
+    ... <= with_file1
+    ...    with_file2
+    ... path = mydata2
+    ... ''')
+
+    >>> print system(buildout),
+    Installing myfiles.
+      color='blue'
+      file1='mydata/file1'
+      file2='mydata/file2'
+      path='mydata'
+      recipe='zc.buildout:debug'
+    Installing myfiles2.
+      color='blue'
+      file1='mydata2/file1'
+      file2='mydata2/file2'
+      path='mydata2'
+      recipe='zc.buildout:debug'
+    """
+
 ######################################################################
 
 def make_py_with_system_install(make_py, sample_eggs):
-- 
1.7.8.3