After update to version 2.0, got an error in HTML5Translator

[madTeddy]

About the bug
After update to Sphinx 2.0, got an error in HTML5Translator when making html. It's cause my extension, but i don't know what's wrong. In Sphinx 1.8.5 all was fine.

Traceback

# Sphinx version: 2.0.0
# Python version: 3.7.3 (CPython)
# Docutils version: 0.14 
# Jinja2 version: 2.10
# Last messages:
#   none found
#   pickling environment...
#   done
#   checking consistency...
#   done
#   preparing documents...
#   done
#   writing output... [ 14%] ***
#   writing output... [ 28%] ***
#   writing output... [ 42%] ***
# Loaded extensions:
#   sphinx.ext.mathjax (2.0.0) from c:\users\madteddy\appdata\local\programs\python\python37-32\lib\site-packages\sphinx\ext\mathjax.py
#   sphinxcontrib.applehelp (1.0.1) from c:\users\madteddy\appdata\local\programs\python\python37-32\lib\site-packages\sphinxcontrib\applehelp\__init__.py
#   sphinxcontrib.devhelp (1.0.1) from c:\users\madteddy\appdata\local\programs\python\python37-32\lib\site-packages\sphinxcontrib\devhelp\__init__.py
#   sphinxcontrib.htmlhelp (1.0.1) from c:\users\madteddy\appdata\local\programs\python\python37-32\lib\site-packages\sphinxcontrib\htmlhelp\__init__.py
#   sphinxcontrib.serializinghtml (1.1.3) from c:\users\madteddy\appdata\local\programs\python\python37-32\lib\site-packages\sphinxcontrib\serializinghtml\__init__.py
#   sphinxcontrib.qthelp (1.0.2) from c:\users\madteddy\appdata\local\programs\python\python37-32\lib\site-packages\sphinxcontrib\qthelp\__init__.py
#   alabaster (0.7.12) from c:\users\madteddy\appdata\local\programs\python\python37-32\lib\site-packages\alabaster\__init__.py
#   myext.myextension(unknown version) from D:\Python\docs\source\_ext\myext\myextension.py
Traceback (most recent call last):
  File "c:\users\madteddy\appdata\local\programs\python\python37-32\lib\site-packages\sphinx\cmd\build.py", line 284, in build_main
    app.build(args.force_all, filenames)
  File "c:\users\madteddy\appdata\local\programs\python\python37-32\lib\site-packages\sphinx\application.py", line 338, in build
    self.builder.build_update()
  File "c:\users\madteddy\appdata\local\programs\python\python37-32\lib\site-packages\sphinx\builders\__init__.py", line 326, in build_update
    len(to_build))
  File "c:\users\madteddy\appdata\local\programs\python\python37-32\lib\site-packages\sphinx\builders\__init__.py", line 389, in build
    self.write(docnames, list(updated_docnames), method)
  File "c:\users\madteddy\appdata\local\programs\python\python37-32\lib\site-packages\sphinx\builders\__init__.py", line 569, in write
    self._write_serial(sorted(docnames))
  File "c:\users\madteddy\appdata\local\programs\python\python37-32\lib\site-packages\sphinx\builders\__init__.py", line 580, in _write_serial
    self.write_doc(docname, doctree)
  File "c:\users\madteddy\appdata\local\programs\python\python37-32\lib\site-packages\sphinx\builders\html.py", line 646, in write_doc
    self.docwriter.write(doctree, destination)
  File "c:\users\madteddy\appdata\local\programs\python\python37-32\lib\site-packages\docutils\writers\__init__.py", line 80, in write
    self.translate()
  File "c:\users\madteddy\appdata\local\programs\python\python37-32\lib\site-packages\sphinx\writers\html.py", line 59, in translate
    self.document.walkabout(visitor)
  File "c:\users\madteddy\appdata\local\programs\python\python37-32\lib\site-packages\docutils\nodes.py", line 174, in walkabout
    if child.walkabout(visitor):
  File "c:\users\madteddy\appdata\local\programs\python\python37-32\lib\site-packages\docutils\nodes.py", line 174, in walkabout
    if child.walkabout(visitor):
  File "c:\users\madteddy\appdata\local\programs\python\python37-32\lib\site-packages\docutils\nodes.py", line 174, in walkabout
    if child.walkabout(visitor):
  File "c:\users\madteddy\appdata\local\programs\python\python37-32\lib\site-packages\docutils\nodes.py", line 166, in walkabout
    visitor.dispatch_visit(self)
  File "c:\users\madteddy\appdata\local\programs\python\python37-32\lib\site-packages\docutils\nodes.py", line 1882, in dispatch_visit
    return method(node)
  File "c:\users\madteddy\appdata\local\programs\python\python37-32\lib\site-packages\sphinx\writers\html5.py", line 850, in visit_field
    self._fieldlist_row_index += 1
AttributeError: 'HTML5Translator' object has no attribute '_fieldlist_row_index'

Environment info

• OS: Windows 10 x64
• Python version: 3.7.3
• Sphinx version: 2.0.0
• Sphinx extensions: myext.myextension

[tk0miya]

I guess your extension has generated a field node not having field_list as a parent.

It seems HTML5 writer does not initialize the variable on constructor. But I feel your extension generates wrong doctrees. Could you check it please?
refs: http://docutils.sourceforge.net/docs/ref/doctree.html#field

[madTeddy]

I guess your extension has generated a field node not having field_list as a parent.

It seems HTML5 writer does not initialize the variable on constructor. But I feel your extension generates wrong doctrees. Could you check it please?
refs: http://docutils.sourceforge.net/docs/ref/doctree.html#field

Yep, i'm using a field without field_list as a parent. But in sphinx 1.8.5 i'm using field like an empty node for another childrens, and it's working fine...

I changed fields on inline nodes and all working fine now.

[tk0miya]

I just merged #6267 now. So you can use it as before.

But docutils and Sphinx consider a field node is a part of field_list, and it also contains field_name and field_body as children. So it is better to replace it to another kind of nodes.