crash in edit book due to pyqt API change

[Andreas Metzler]

Hello,

this is https://bugs.debian.org/823134 originally reported by Douglas Perkins:
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After a update and upgrade in late April 2016, editing in Calibre stopped working.

If I open Calibre, right-click and edit an ePub book stored there, and then try to open an HTML file in the book, I get a pop-up error message.

---

calibre, version 2.55.0
ERROR: Unhandled exception: <b>AttributeError</b>:type object 'QUrl' has no attribute 'None'

calibre 2.55 embedded-python: False is64bit: True
Linux-4.4.0-1-amd64-x86_64-with-debian-stretch-sid Linux ('64bit', 'ELF')
('Linux', '4.4.0-1-amd64', '#1 SMP Debian 4.4.2-3 (2016-02-21)')
Python 2.7.11+
Linux: ('debian', 'stretch/sid', '')
Traceback (most recent call last):
  File "/usr/lib/calibre/calibre/gui2/tweak_book/preview.py", line 224, in createRequest
    url = unicode(request.url().toString(QUrl.None))
AttributeError: type object 'QUrl' has no attribute 'None'

---

After I click OK for the error message popup, Calibre closes.
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Tobias Brink later added this information:
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The problem seems to be related to a recent python-pyqt5 update to version 5.6.
They seem to have helpfully broken the API: "PyQt5.Qt.QUrl.None" is now named
"PyQt5.Qt.QUrl.None_" as far as I can see. Great. Maybe there are other
problems after fixing this one, too, the upstream changelog for pyqt5 does not
mention this from what I can tell at a quick glance.
[...]
BTW, if you need a quick hack to fix this, run the following as root:

dpkg -L calibre | grep py$ | xargs sed -i 's/QUrl\.None/QUrl.None_/g'

Warning: This will edit the package's files (see debsums errors in the
information below). Still, this makes the program usable until the next update.
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Bug was reported against 2.55, but afaict GIT head has no changes related to the issue.

Thanks, cu Andreas

[Eli Schwartz (eschwartz)]

Coincidentally, this was just fixed today in git: https://github.com/kovidgoyal/calibre/commit/57450e54e68b3ca155f7ac16983632b6bd458bc6