matplotlib/matplotlib — pull request #1247 by pelson (2012-09-14 09:55:32+00:00)
Title: Log axvline

Fixes the exception in from #1246 of:
```
ValueError: It is not possible to compute transA - transB since transB
cannot be inverted and there is no shortcut possible.
```

The fix was simple enough (added the has_inverse property to the Log transforms). The generated png for the tests looks perfect, unfortunately the PDF and SVGs are not. Strangely, when I run this from a script rather than from the tests, the PDF and SVGs are perfect, but the png produces a line in the wrong place. If anyone has any ideas what may be going on there, it would be greatly appreciated.

As it is, this is a bona fide bug fix, but there still exists some weirdness to investigate.