Fix for re-ordering plugins when JS provides language as empty string

[damianmoore]

I was having a problem where I couldn't re-order plugins within a placeholder, similar to this issue: #3058

This caused an error to popup on move "order parameter did not have all plugins of the same level in it" and then the move plugin would be removed.

I found that the move_plugin() method of admin/placeholderadmin.py was not finding the other plugins correctly as it was searching for a language of '' (empty string) rather than the language that the plugins had ('en-gb'). This is because the JavaScript POST included a plugin_language of empty string.

As far as I can see, this JS variable comes from a GET parameter of the request so is not reliably there. Falling back to the language of the plugin seems a sensible fix to me.

Maybe there is some extra configuration would otherwise solve this, but I can't find it.

[johnraz]

Just being curious what did you set CMS_LANGUAGE settings to?

[coveralls]

Coverage decreased (-0.17%) when pulling 3889b11 on damianmoore:fix_for_plugin_ordering into 2d3e10a on divio:develop.

[damianmoore]

@johnraz I don't have CMS_LANGUAGES set in my settings as it's not a multi-lingual site. The variable is not mentioned here so I assume it's not required: http://docs.django-cms.org/en/latest/getting_started/installation/integrate.html#configuration-and-setup . I do have LANGUAGE_CODE = 'en-gb', though and this seems to be what the plugin instances languages are being set to.

[johnraz]

Ok same thing happen to me without CMS_LANGUAGES... I guess there may be a relation :-)

[johnraz]

@yakky : side note regarding the travis build, same issue as on my other PR ... seems something is broken ❌

[yakky]

Please rebase against develop

[damianmoore]

@yakky rebased

[coveralls]

Coverage decreased (-0.09%) to 88.022% when pulling 7b924de on damianmoore:fix_for_plugin_ordering into 2d3e10a on divio:develop.

[yakky]

Thanks