genshi Transformer Substitute Transformation performs replacement across the document instead of selected nodes

[jhammel@…]

When doing a Transform(<xpath>).substitute(from, to) transformation, everything in the document that matches from is substituted instead of just elements matching the xpath expression:

>>> html2
<genshi.core.Stream object at 0xb7dba42c>
>>> print html2
<b>foo</b><i>fee</i>
>>> print html2 |  Transformer('//b').replace('replaced')
replaced<i>fee</i>
>>> print html2 |  Transformer('//b').substitute('f', 'g')
<b>goo</b><i>gee</i>

Even though <i>fee</i> shouldn't be matched because it is not in the xpath (as evidenced by the preceding replace call), the substitution is erroneously performed.

I believe this is due to a missing check around here:

​http://genshi.edgewall.org/browser/trunk/genshi/filters/transform.py#L871

I have fixed this locally by replacing this line with the following:

            if kind is TEXT and mark is not None:

I'm not sure if this is a good fix, but it does get the above test example to correctly display:

>>> print html2 | Transformer('//b').substitute('f', 'g')
<b>goo</b><i>fee</i>

[athomas]

Fixed in r852. Thanks jhammel!