Sphinx (documentation tool): set tab width in output

Question

How do you set tab width in HTML output of Sphinx code snippets highlighted by Pygments? By default it is the annoying 8, but I want 4. Did not find a word about this setting in Sphinx conf.py.

Answer 1

You will need to write a Sphinx Extension. Add your custom Lexer, and apply it with VisibleWhitespaceFilter.

Answer 2

Add something like this to your conf.py:

import re

def process_docstring(app, what, name, obj, options, lines):
    spaces_pat = re.compile(r"( {8})")
    ll = []
    for l in lines:
        ll.append(spaces_pat.sub("    ",l))
    lines[:] = ll

def setup(app):
    app.connect('autodoc-process-docstring', process_docstring)

See also Sphinx Docstring preprocessing documentation.

Answer 3

I asked the same question on sphinx-dev group and it turns out it's a problem with Docutils which is used by Sphinx. Docutils replace all tabs with 8 spaces and currently there is no way to change that value from Sphinx.

http://groups.google.com/group/sphinx-dev/browse_thread/thread/35b8071ffe9a8feb

The only feasible solution seems to be to follow the advice from S.Lott and John Paulett in comments to my question -- use spaces instead of tabs.