SVG unknown char messages when SVG output is not set

[pkra]

Originally reported at pkra/mathjax-node-page#56.

The following will produce "SVG - Unknown character: U+C in MathJax_Main,MathJax_Size1,MathJax_AMS" etc.

var mjAPI = require("mathjax-node");
mjAPI.typeset({
  math: 'a = \frac{\text{some text with umlauts äöü}}{1.23}',
  format: "TeX", // "inline-TeX", "MathML"
  mml:true,
}, function (data) {
  if (!data.errors) {console.log(data.mml)}
});

On the other hand, there are no MML Unknown Char messages so I'm guessing the message hooks are not set up correctly. Maybe they should just be independent of the output anyway?

[dpvc]

Because the MathML output is generated by the toMathML() method rather than the NativeMML output jax, it turns out that the output renderer is always set either to CommonHML or SVG (in this case, SVG). That is why you are getting the SVG messages (and why the OP was getting the SVG cache node).

The unknown characters are output-jax dependent: they are generated by the various output renderers based on the font the render has loaded; that can vary depending on the configuration and the renderer, so can't be independent of that. Also, the NativeMML output doesn't have font data, so there shouldn't be any messages for that case.

So the only error here is that the SVG warnings shouldn't be produced.

Note also that you should have \\frac and \\text, not \frac and \text, as \f will produce a form-feed (the source of your undefined U+000C message), and \t will produce a tab.

[dpvc]

I've made a pull request to fix the issue.

[dpvc]

==> Merged.