=================================== FAILURES ===================================
_________________ TestProofreadPageValidSite.test_json_format __________________
self = <tests.proofreadpage_tests.TestProofreadPageValidSite testMethod=test_json_format>
    def test_json_format(self):
        """Test conversion to json format."""
        page = ProofreadPage(self.site, self.valid['title'])
    
        rvargs = {'rvprop': 'ids|flags|timestamp|user|comment|content',
                  'rvcontentformat': 'application/json',
                  'titles': page,
                  }
    
        rvgen = self.site._generator(api.PropertyGenerator,
                                     type_arg='info|revisions',
                                     total=1, **rvargs)
        rvgen.set_maximum_items(-1)  # suppress use of rvlimit parameter
    
        try:
>           pagedict = next(iter(rvgen))
tests/proofreadpage_tests.py:278: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
pywikibot/data/api.py:3126: in __iter__
    for result in super(PropertyGenerator, self).__iter__():
pywikibot/data/api.py:2950: in __iter__
    self.data = self.request.submit()
pywikibot/data/api.py:2428: in submit
    self._data = super(CachedRequest, self).submit()
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
self = tests.TestRequest<wikisource:en->'/w/api.php?maxlag=5&continue=&format=json&rv...olume+1.djvu/12&meta=userinfo&indexpageids=&rvslots=*&uiprop=blockinfo|hasmsg'>
    def submit(self):
        """
            Submit a query and parse the response.
    
            @return: a dict containing data retrieved from api.php
            @rtype: dict
            """
        self._add_defaults()
        use_get = self._use_get()
    
        while True:
            paramstring = self._http_param_string()
    
            simulate = self._simulate(self.action)
            if simulate:
                return simulate
    
            if self.throttle:
                self.site.throttle(write=self.write)
            else:
                pywikibot.log(
                    "Submitting unthrottled action '{0}'.".format(self.action))
    
            use_get, uri, body, headers = self._get_request_params(use_get,
                                                                   paramstring)
            rawdata, use_get = self._http_request(use_get, uri, body, headers,
                                                  paramstring)
            if rawdata is None:
                continue
    
            result = self._json_loads(rawdata)
            if result is None:
                continue
    
            if self._userinfo_query(result):
                continue
    
            self._handle_warnings(result)
    
            if "error" not in result:
                return result
    
            error = result['error'].copy()
            for key in result:
                if key in ('error', 'warnings'):
                    continue
                assert key not in error
                assert isinstance(result[key], basestring), \
                    'Unexpected %s: %r' % (key, result[key])
                error[key] = result[key]
    
            if "*" in result["error"]:
                # help text returned
                result['error']['help'] = result['error'].pop("*")
            code = result['error'].setdefault('code', 'Unknown')
            info = result['error'].setdefault('info', None)
    
            if not self._logged_in(code):
                continue
    
            if code == "maxlag":
                lag = lagpattern.search(info)
                pywikibot.log('Pausing due to database lag: ' + info)
                if lag:
                    lag = lag.group('lag')
                self.site.throttle.lag(int(lag or 0))
                continue
    
            elif code == 'help' and self.action == 'help':
                # The help module returns an error result with the complete
                # API information. As this data was requested, return the
                # data instead of raising an exception.
                return {'help': {'mime': 'text/plain',
                                 'help': result['error']['help']}}
    
            pywikibot.warning('API error %s: %s' % (code, info))
    
            if self._internal_api_error(code, error, result):
                continue
    
            # Phab. tickets T48535, T64126, T68494, T68619
            if code == "failed-save" and \
               self.action == 'wbeditentity' and \
               self._is_wikibase_error_retryable(result["error"]):
                self.wait()
                continue
    
            # If readapidenied is returned try to login
            if code == 'readapidenied' and self.site._loginstatus in (-3, -1):
                self.site.login()
                continue
    
            if self._bad_token(code):
                continue
    
            if 'mwoauth-invalid-authorization' in code:
                if 'Nonce already used' in info:
                    pywikibot.error(
                        'Retrying failed OAuth authentication for {0}: {1}'
                        .format(self.site, info))
                    continue
                raise NoUsername('Failed OAuth authentication for %s: %s'
                                 % (self.site, info))
            if code == 'cirrussearch-too-busy-error':  # T170647
                self.wait()
                continue
    
            # raise error
            try:
                # Due to bug T66958, Page's repr may return non ASCII bytes
                # Get as bytes in PY2 and decode with the console encoding as
                # the rest should be ASCII anyway.
                param_repr = str(self._params)
                if PY2:
                    param_repr = param_repr.decode(config.console_encoding)
                pywikibot.log(u"API Error: query=\n%s"
                              % pprint.pformat(param_repr))
                pywikibot.log(u"           response=\n%s"
                              % result)
    
>               raise APIError(**result['error'])
E               APIError: invalidparammix: The "rvcontentformat" parameter cannot be used with "rvslots". [help:See https://en.wikisource.org/w/api.php for API usage. Subscribe to the mediawiki-api-announce mailing list at &lt;https://lists.wikimedia.org/mailman/listinfo/mediawiki-api-announce&gt; for notice of API deprecations and breaking changes.]
pywikibot/data/api.py:2273: APIError