unicode-math causes a wider 7

[teepeemm]

It appears that loading unicode-math causes the digit 7 to be wider than expected:

\documentclass{article}
\usepackage{unicode-math}
\usepackage{siunitx}
\begin{document}
\begin{tabular}{ S[table-format=1]}
0\\
1\\
2\\
3\\
4\\
5\\
6\\
7\\
8\\ % line 14
9
\end{tabular}
\end{document}

has the warning

Overfull \hbox (0.13pt too wide) detected at line 14
$\TU/latinmodern-math.otf(1)/m/n/10 7$

(Using \setlength\overfullrule{1pt} shows that it's the 7 on line 13, not the 8 on line 14.)

[josephwright]

From a recent source of my own :-)

% Spotted an issue with Latin Modern Math: it has a weird width for "7."!
% Fix for LuaTeX
\AtBeginDocument{\mathitalicsmode=2 }

Basically, I am not sure what to do here for the general case. As far as I can see, the 'fix' is not generally applicable, and I have real way to get the font sorted (which is what is really needed). Perhaps one for @zauguin magic to do something in the Lua!

[josephwright]

To be clear, one issue is I cannot fix for XeTeX at all - it's simply wrong at the font level and as LM is frozen, we are stuck :-(

[zauguin]

The font can be patched on the fly with

\documentclass{article}
\usepackage{unicode-math}
\usepackage{siunitx}
\directlua{
  local function remove_digit_ic(tfmdata)
    local characters = tfmdata.characters
    for cp=string.byte'0', string.byte'9' do characters[cp].italic = nil end
    return tfmdata
  end
  fonts.constructors.features.otf.register {
    name = 'digit_no_ic',
    description = 'Remove italic correction from digits',
    default = true,
    initializers = {
      base = remove_digit_ic,
    },
  }
}
\setmathfont{Latin Modern Math}[RawFeature=digit_no_ic]
\begin{document}
\begin{tabular}{ S[table-format=1]}
0\\
1\\
2\\
3\\
4\\
5\\
6\\
7\\
8\\
9
\end{tabular}
\end{document}

We should probably add a more automated way to apply a recommended set of fixes at least for the latin modern fonts though instead of doing ad-hoc fixes in a document.