#341 "unexpected indent" warning does note cite most recent mark-up construct

[jfbu]

Consider this test:

======
 TEST
======

First case:

This will output::

  b'1
'

Second case:

        This will output::

          b'1
'

Then:

$ rst2html.py test.rst test.html
test.rst:10: (WARNING/2) Literal block ends without a blank line; unexpected unindent.
test.rst:17: (WARNING/2) Block quote ends without a blank line; unexpected unindent.

In second case, it may divert user from root cause. Real life example comes from unescaped backslashes in a docstring, https://github.com/sphinx-doc/sphinx/issues/4479

Because the docstrings has the spaces naturally, the "Block quote ends without a blank line" warning was emitted. This led to further confusion with quotes as in typographical quotes, (of course that's not due to Docutils ;-)), and I guess perhaps user could have found the explanation easier if message had been of type "Literal block ends without...".

[Günter Milde]

This is expected behaviour: The indentation of the next paragraph determines whether it ends the outer block element or a nested block element. The following example should make this clear:

Standard paragraph

   * List 
   * in a quote
next paragraph (not nested)

   * List 
   * in a quote
   next paragraph (nested)

next paragraph (not nested) 

The non-nested paragraph ends the block-quote while the nested paragraph just ends the list (at least this is what they will do if properly separated.

I agree that the original issue is unfortunately hard to detect. Backslashes in docstrings are a trap. However, the remedy here is IMO proper documentation of the Python string handling and an advise to print docstrings out via Python in case of problems -- to see how they reach Sphinx/Docutils.