Merge lp:~mterry/sessioninstaller/no-defer-twice into lp:sessioninstaller

[Michael Terry]

Back in the day, I tried to fix bug 848605 with r130.

But that caused bug 1042231, fixed in r132.

But r132 re-opened the original issue. This branch hopefully fixes both issues.

Just checking for deferred call state was the simplest fix I could think of. We still need error_handler in case there is such a problem in aptdaemon that it never even gets to emit "finished".

Though in cases like bug 1056545, aptdaemon calls error_handler because it times out, but then later the dialog emits "finished" when the user cancels the policykit prompt. So we should guard against that.

[Michael Vogt (mvo)]

Looked good to me, thanks.

review: Approve

[Martin Pitt (pitti)]

I actually merged this now.

=== modified file 'sessioninstaller/backends/aptd.py'
--- sessioninstaller/backends/aptd.py	2012-09-19 12:37:26 +0000
+++ sessioninstaller/backends/aptd.py	2013-03-14 19:04:35 +0000
@@ -54,6 +54,8 @@
         return deferred
 
     def _on_finished(self, diag, deferred, trans):
+        if deferred.called:
+            return  # Already called, likely from error_handler (LP: #1056545)
         if trans.error:
             deferred.errback(trans.error)
         else: