#241 doctree-based publishing != publish_string

[metagriffin]

i would expect a call to publish_string() and publish_doctree() + publish_from_doctree() with exactly the same arguments to result in identical output, but this is not the case. sample program to illustrate the issue:

from docutils.core import *

rst = '''\
My Document
===========

.. meta::
  :my-custom-header: my-custom-value
'''

settings = {
  'output_encoding': 'UTF-8',
  'stylesheet_path': None,
  }

sOut  = publish_string(rst, writer_name='html', settings_overrides=settings)
dtree = publish_doctree(rst)
dOut  = publish_from_doctree(dtree, writer_name='html', settings_overrides=settings)

# this assert passes
assert '<meta content="my-custom-value" name="my-custom-header" />' in sOut

# these asserts fail
assert '<meta content="my-custom-value" name="my-custom-header" />' in dOut
assert sOut == dOut

note that besides the meta directive missing in the doctree version, everything else looks the same.

[Günter Milde]

The "meta" directive is "HTML-only", it creates a pending node that is removed by the "Filter" transform if the writer is not "HTML".

It seems the "Filter" transform is run by publish_doctree() but should be run by publish_from_doctree() instead because only then the writer is known.

Actually, the "Filter" transform should be run by both, publish_doctree() and publish_from_doctree() but only apply changes if the component_type is "reader" in the first case and if component_type is "writer" in the second.

Patches welcome.

[Günter Milde]

The components.Filter transform is only used for post-processing the "meta" directive's content. When <meta> becomes a standard Docutils doctree node (as planned), the transform is no longer required and the described behaviour will be fixed.

[Günter Milde]

"meta" is now a standard node and the "filter" directive no longer required.

[Günter Milde]

Fixed in Docutils 0.18. Thanks again for the report.