luaotfload: reading database

[hvoss49]

The following example worked last year:

\documentclass{article}
\setlength{\parindent}{0em}
\usepackage{fontspec}
\usepackage{luacode}
\newfontface\LMML{Latin Modern Mono Light Cond}%% Für die Ausgabe

\begin{luacode}
local teststring = "\\LaTeX~--~Eine Einführung."
local myfonts = luaotfload.aux.read_font_index()
function printFontDemo(fontname)
  local fnA = string.lower(fontname)
  local a = {}
  local b = {}
  for i, v in ipairs(myfonts.mappings) do
    m, n = string.find(string.lower(v.familyname),fnA)
    if m then
      a[v.fontname] = v.familyname
      b[#b + 1] = v.fontname
    end
  end
  table.sort(b)
  for i, v in ipairs(b) do
    tex.print("\\parbox{0.21\\linewidth}{\\LMML\\footnotesize")
    tex.print(-2, a[v])
    tex.print("\\\\ \\scriptsize")
    tex.print(-2, v)
    tex.print("}\\parbox{0.79\\linewidth}{\\raggedright\\setmainfont{" .. v .. "}")
    tex.print(teststring)
    tex.print("}\\\\[2pt]")
  end
end
\end{luacode}
\begin{document}
\directlua{printFontDemo("LatinModern")}
\end{document}

now I get with lualatex 0.95 and up-to-date TL2016

[...]
(/usr/local/texlive/2016/texmf-dist/tex/luatex/ctablestack/ctablestack.sty)))(l
oad luc: /usr/local/texlive/2016/texmf-var/luatex-cache/generic/fonts/otl/lmmon
oltcond10-regular.luc) (./12-04-19.aux)[\directlua]:7: bad argument #1 to 'ipai
rs' (table expected, got nil)
stack traceback:
	[C]: in function 'ipairs'
	[\directlua]:7: in function 'printFontDemo'
	[\directlua]:1: in main chunk.
l.35 \directlua{printFontDemo("LatinModern")}
                                           
? 

I can fix it with the following. Is it a problem with my code or the database which has an empty entry?

  for i, v in ipairs(myfonts.mappings) do
    if v.familyname then
      m, n = string.find(string.lower(v.familyname),fnA)
      if m then
        a[v.fontname] = v.familyname
        b[#b + 1] = v.fontname
      end
    end
  end

[phi-gamma]

Thank you for reporting! 2017-02-05 (Sunday), notifications@github.com (hvoss49):

``` [...] (/usr/local/texlive/2016/texmf-dist/tex/luatex/ctablestack/ctablestack.sty)))(l oad luc: /usr/local/texlive/2016/texmf-var/luatex-cache/generic/fonts/otl/lmmon oltcond10-regular.luc) (./12-04-19.aux)[\directlua]:7: bad argument #1 to 'ipai rs' (table expected, got nil) stack traceback: [C]: in function 'ipairs' [\directlua]:7: in function 'printFontDemo' [\directlua]:1: in main chunk. l.35 \directlua{printFontDemo("LatinModern")} ? ``` I can fix it with the following. Is it a problem with my code or the database which has an empty entry?

I’m curious about that empty entry. Is it literally empty or just missing the fields you access? Does the empty one get created if you force reindexing?

[hvoss49]

The familyname of the font is nil:

[...]
1843: countriesofeurope
1844: vrinda
1845: nil
[\directlua]:10: bad argument #1 to 'lower' 
(string expected, got nil)
stack traceback:
	[C]: in function 'lower'
	[\directlua]:10: in function 'printFontDemo'
	[\directlua]:1: in main chunk.
l.38 \directlua{printFontDemo("LatinModern")}
                                           
? X

the fonts from luaotfload-names are:

[...]
, "/usr/share/fonts/truetype/lohit-punjabi/Lohit-Punjabi.ttf"
, "/usr/local/share/fonts/CountriesofEurope.otf"
, "/usr/local/share/fonts/vrinda.ttf"
, "/usr/local/share/fonts/epkyouka.ttf"
, "/usr/local/share/fonts/GohaTibebZemen.otf"
, "/usr/local/share/fonts/manchu.ttf"
[...]

I can delete the vrinda.ttf and epkyouka.ttf and then get the same problem with another font.
The header of epkyouka.ttf:

Family:              EPSON Kyoukashoutai
Subfamily:           Regular
Full name:           EPSON Kyoukashoutai
PostScript name:     -Regular
Version:             Version 3.00
Unique ID:           -Regular-2012:10:10
Trademark:           EPSON Kyoukashoutai  and EPSON-KYOKASHO is a trademark of SEIKO EPSON CORPORATION.
Copyright:            - Created with Type 3.2
Vendor ID:           EPSN

The PostScript name is a bit curious ...

[hvoss49]

I had a lot of such fonts which gave nil in the list. After deleting all it works. That were all ttf fonts. Let me know if you need one of the fonts for testing.

[phi-gamma]

2017-02-06 (Monday), notifications@github.com (hvoss49):

I had a lot of such fonts which gave nil in the list. After deleting all it works. That were all ttf fonts. Let me know if you need one of the fonts for testing.

This should print a list of all of them: $ luaotfload-tool --list="*" --fields="fontname,familyname" | cat -n | column -t | grep '<none>' Honestly I haven’t a single speciment in my test collection that exhibits this behavior. Since there are two fallbacks for that field in place, I suspect either a parsing error or a completely borked names table. For the normal lookup this matters little. The files are simply ignored when building the families table so they can only be matched by name (or filename of course). As far as Luaotfload is concerned, this appears to work as intended. But since those files could be interesting, I think it’d be best if you email me an example file. Best, Philipp