# HG changeset patch
# User Mads Kiilerich <mads@kiilerich.com>
# Date 1340927508 -7200
# Node ID 0e4171fdb9d4267aa1145b840529d75673ea553d
# Parent  1bd18c415eec578b5a8cc3bb61c65e554f4674e1
convert: check for failed svn import in debugsvnlog and abort cleanly

'hg debugsvnlog' failed with a crash when using the uninitialized transport in
get_log_child if the import of the svn libraries had failed.

'convert' should never get as far as launching 'hg debugsvnlog' if the svn
libraries are missing, but by launching a subprocess there is risk that the
environment is mangled so the second import fails.

It is in principle also possible to launch the command manually.

diff -r 1bd18c415eec -r 0e4171fdb9d4 hgext/convert/subversion.py
--- a/hgext/convert/subversion.py	Thu Jun 28 03:41:37 2012 +0200
+++ b/hgext/convert/subversion.py	Fri Jun 29 01:51:48 2012 +0200
@@ -120,6 +120,10 @@
     """Fetch SVN log in a subprocess and channel them back to parent to
     avoid memory collection issues.
     """
+    if svn is None:
+        raise util.Abort(_('debugsvnlog could not load Subversion python '
+                           'bindings'))
+
     util.setbinary(sys.stdin)
     util.setbinary(sys.stdout)
     args = decodeargs(sys.stdin.read())