ImageMacro may fail on WikiStart page

[Shun-ichi Goto <gotoh@…>]

As same issue with #1802, ImageMacro? raises exception.
There's a workaround patch until formatter provides correct path info.
This patch also contains bug fix of split count to retrieve 'id' part correctly.

--- macros.py	(revision 2017)
+++ macros.py	(working copy)
@@ -314,7 +314,9 @@
             # FIXME: should be retrieved from the formatter...
             # ...and the formatter should be provided to the macro
             file = filespec
-            module, id = req.hdf['HTTP.PathInfo'].split('/', 3)[1:]
+            items = req.hdf['HTTP.PathInfo'].split('/', 2) + [None, None]
+            module = items[1] or 'wiki'
+            id = items[2] or 'WikiStart'
             if module not in ['wiki', 'ticket']:
                 raise Exception('Cannot reference local attachment from here')
         else:

[cboos]

My idea is that any wiki text in Trac always belongs to some
Trac object (see TracObjectModelProposal).
Sometimes, there's only one wiki text for a given Trac object,
like the content for a Wiki page.
Sometimes there are more of them, e.g. a ticket object
has the description plus any number of distinct comments.

You can see those concepts "at work" in the TracCrossReferences branch,
where I call those wiki texts the facets of an object.

On that branch, I'll refactor the wiki formatting methods
into member methods of the generic
TracObject.

I don't think it's a good idea to refactor the trunk so that
the wiki formatting methods take into account the (type,id)
of the "object" to which the wiki text being formatted belongs,
because that would be an extensive change which would conflict
with the direction taken by the TracCrossReferences branch.

So in the meantime, I'll apply your patch.

[mgood]

Looks like cboos checked in [2018], but forgot to close this ticket.