Use rst_prolog and rst_epilog only for rst files?

[mgeier]

Apparently, Sphinx adds those to all source files, regardless if those are actually reST files or not.

This leads to problems with some custom source_parsers, e.g. spatialaudio/nbsphinx#38

I think rst_prolog and rst_epilog should only be prepended/appended for actual reST files.
Is there anything speaking against this?

[birkenfeld]

No, that makes a lot of sense. Should be a bugfix for 1.4.2.

[cmdcolin]

I might want to apply replacements in markdown for example (using recommonmark or similar), so it would be actually nice to preserve some way to do replacements on non RST.

I wasn't actually even getting the rst_epilog to work on markdown though so I am not sure if it's just me or not but this would be a nice-to-have for markdown :)

[tk0miya]

Fixed at 9cd5ba9.

BTW, rst_prolog is not related with substitution feature directly.
It is a feature of reStructured Text itself. so I think new feature is needed to substitute for markdown or other format.
Now, Sphinx emits source-read event for third party extensions. It might support to make extensions which supports substitution on markdowns.