problems saving a page with empty text - Pywikipedia-l

28 May 2014

My first experience with pywikibot, downloaded core, i wanted to change
a few pages. Immediately ran into an error when trying to set a page's
text to empty. The error message was unhelpful, but I dug through the
source and found the issue. I'd like to suggest that 2 things:

1. Setting a page's text to be empty should be allowed

2. If not, at least the error should be fixed to actually show the
correct error, explained below.

Here is an example script, and the error when running it

import pywikibot
site = pywikibot.Site()
page = pywikibot.Page(site, "MediaWiki:Lastmodifiedat")
page.text = ""
page.save()

Logging in to ianwiki:en as Ian Kelling
Traceback (most recent call last):
  File "pwb.py", line 143, in <module>
    run_python_file(fn, argv, argvu)
  File "pwb.py", line 67, in run_python_file
    exec(compile(source, filename, "exec"), main_mod.__dict__)
  File "scripts/iansetup.py", line 5, in <module>
    page.save()
  File "/a/opt/pywikibot/pywikibot/page.py", line 858, in save
    **kwargs)
  File "/a/opt/pywikibot/pywikibot/page.py", line 884, in _save
    raise pywikibot.PageNotSaved("%s: %s" % (link, err))
pywikibot.exceptions.PageNotSaved
CRITICAL: Waiting for 1 network thread(s) to finish. Press ctrl-c to abort
<class 'pywikibot.exceptions.PageNotSaved'>

The cause is in site.py, in def editpage, line 2699:

        if not text:
            raise Error("editpage: no text to be saved")

This error should be shown instead of the one that is actually shown.