How to properly use html-to-react? - html

Question

so i am learning about this package html-to-react, and for the most part, i understand it. However, their is a piece of code i just cannot seem to be able to get my head around. The code is:
var React = require('react');
var HtmlToReact = require('html-to-react');
var HtmlToReactParser = require('html-to-react').Parser;
var htmlToReactParser = new HtmlToReactParser();
var htmlInput = '<div><div data-test="foo"><p>Text</p><p>Text</p></div></div>';
var htmlExpected = '<div><div data-test="foo"><h1>Heading</h1></div></div>';
var isValidNode = function () {
return true;
};
var processNodeDefinitions = new HtmlToReact.ProcessNodeDefinitions(React);
// Order matters. Instructions are processed in
// the order they're defined
var processingInstructions = [
{
// This is REQUIRED, it tells the parser
// that we want to insert our React
// component as a child
replaceChildren: true,
shouldProcessNode: function (node) {
return node.attribs && node.attribs['data-test'] === 'foo';
},
processNode: function (node, children, index) {
return React.createElement('h1', {key: index,}, 'Heading');
}
},
{
// Anything else
shouldProcessNode: function (node) {
return true;
},
processNode: processNodeDefinitions.processDefaultNode,
},
];
var reactComponent = htmlToReactParser.parseWithInstructions(
htmlInput, isValidNode, processingInstructions);
var reactHtml = ReactDOMServer.renderToStaticMarkup(
reactComponent);
assert.equal(reactHtml, htmlExpected);
The code i don't understand is the:
shouldProcessNode: function (node) {
return node.attribs && node.attribs['data-test'] === 'foo';
},
Any help would be very appreciated. Thanks