mmltosvg : Getting "TypeError: Cannot read property 'chars' of undefined" for specific mathml equation

[senthilsam]

Hi I am running mml2svg under direct for converting my mathml to svg. It works perfectly for other mml equations. But when i try converting the below equation it is throwing err.

Input Eqn: <math display='inline'><mrow><msup><mtext>1</mtext><mo>&#x2033;</mo></msup><mo>=</mo><mtext>(</mtext><mi>&#x03C0;</mi><mtext>/648&#x00A0;000)&#x00A0;rad</mtext></mrow></math>

Error: `D:\Senthil\projects\DEV\DTD Validation\MathMltoSvg\mathmltosvgandAlttext-epub\bin\Debug\mjax3-cli\node_modules\mathjax-full\js\core\MathDocument.js:169
finally { if (e_4) throw e_4.error; }
^

TypeError: Cannot read property 'chars' of undefined
at SVGTextNode.CommonWrapper.unicodeChars (D:\Senthil\projects\DEV\DTD Validation\MathMltoSvg\mathmltosvgandAlttext-epub\bin\Debug\mjax3-cli\node_modules\mathjax-full\js\output\common\Wrapper.js:433:48)
at SVGTextNode.SVGWrapper.placeChar (D:\Senthil\projects\DEV\DTD Validation\MathMltoSvg\mathmltosvgandAlttext-epub\bin\Debug\mjax3-cli\node_modules\mathjax-full\js\output\svg\Wrapper.js:206:45)
at SVGTextNode.toSVG (D:\Senthil\projects\DEV\DTD Validation\MathMltoSvg\mathmltosvgandAlttext-epub\bin\Debug\mjax3-cli\node_modules\mathjax-full\js\output\svg\Wrappers\TextNode.js:49:31)
at SVGmo.SVGWrapper.addChildren (D:\Senthil\projects\DEV\DTD Validation\MathMltoSvg\mathmltosvgandAlttext-epub\bin\Debug\mjax3-cli\node_modules\mathjax-full\js\output\svg\Wrapper.js:61:23)
at SVGmo.toSVG (D:\Senthil\projects\DEV\DTD Validation\MathMltoSvg\mathmltosvgandAlttext-epub\bin\Debug\mjax3-cli\node_modules\mathjax-full\js\output\svg\Wrappers\mo.js:63:18)
at SVGmsup.SVGscriptbase.toSVG (D:\Senthil\projects\DEV\DTD Validation\MathMltoSvg\mathmltosvgandAlttext-epub\bin\Debug\mjax3-cli\node_modules\mathjax-full\js\output\svg\Wrappers\scriptbase.js:45:21)
at SVGmrow.SVGWrapper.addChildren (D:\Senthil\projects\DEV\DTD Validation\MathMltoSvg\mathmltosvgandAlttext-epub\bin\Debug\mjax3-cli\node_modules\mathjax-full\js\output\svg\Wrapper.js:61:23)
at SVGmrow.toSVG (D:\Senthil\projects\DEV\DTD Validation\MathMltoSvg\mathmltosvgandAlttext-epub\bin\Debug\mjax3-cli\node_modules\mathjax-full\js\output\svg\Wrappers\mrow.js:27:14)
at SVGinferredMrow.SVGWrapper.addChildren (D:\Senthil\projects\DEV\DTD Validation\MathMltoSvg\mathmltosvgandAlttext-epub\bin\Debug\mjax3-cli\node_modules\mathjax-full\js\output\svg\Wrapper.js:61:23)
at SVGinferredMrow.SVGmrow.toSVG (D:\Senthil\projects\DEV\DTD Validation\MathMltoSvg\mathmltosvgandAlttext-epub\bin\Debug\mjax3-cli\node_modules\mathjax-full\js\output\svg\Wrappers\mrow.js:27:14)`

Any help on this will be much appreciated.

[dpvc]

This is a duplicate of mathjax/MathJax#2402, which will be fixed in the next release. In the meantime, if you add

const SVGWrapper = require('mathjax-full/js/output/svg/Wrapper.js').SVGWrapper;
const CommonWrapper = SVGWrapper.prototype.__proto__;
SVGWrapper.prototype.unicodeChars = function (text, variant) {
  if (!variant) variant = this.variant || 'normal';
  return CommonWrapper.unicodeChars.call(this, text, variant);
}

just after the line

const RegisterHTMLHandler = require('mathjax-full/js/handlers/html.js').RegisterHTMLHandler;

that should work around the problem until then.