import katex from '../katex.mjs'; /* eslint no-constant-condition:0 */ var findEndOfMath = function findEndOfMath(delimiter, text, startIndex) { // Adapted from // https://github.com/Khan/perseus/blob/master/src/perseus-markdown.jsx var index = startIndex; var braceLevel = 0; var delimLength = delimiter.length; while (index < text.length) { var character = text[index]; if (braceLevel <= 0 && text.slice(index, index + delimLength) === delimiter) { return index; } else if (character === "\\") { index++; } else if (character === "{") { braceLevel++; } else if (character === "}") { braceLevel--; } index++; } return -1; }; var escapeRegex = function escapeRegex(string) { return string.replace(/[-/\\^$*+?.()|[\]{}]/g, "\\$&"); }; var amsRegex = /^\\begin{/; var splitAtDelimiters = function splitAtDelimiters(text, delimiters) { var index; var data = []; var regexLeft = new RegExp("(" + delimiters.map(x => escapeRegex(x.left)).join("|") + ")"); while (true) { index = text.search(regexLeft); if (index === -1) { break; } if (index > 0) { data.push({ type: "text", data: text.slice(0, index) }); text = text.slice(index); // now text starts with delimiter } // ... so this always succeeds: var i = delimiters.findIndex(delim => text.startsWith(delim.left)); index = findEndOfMath(delimiters[i].right, text, delimiters[i].left.length); if (index === -1) { break; } var rawData = text.slice(0, index + delimiters[i].right.length); var math = amsRegex.test(rawData) ? rawData : text.slice(delimiters[i].left.length, index); data.push({ type: "math", data: math, rawData, display: delimiters[i].display }); text = text.slice(index + delimiters[i].right.length); } if (text !== "") { data.push({ type: "text", data: text }); } return data; }; /* eslint no-console:0 */ /* Note: optionsCopy is mutated by this method. If it is ever exposed in the * API, we should copy it before mutating. */ var renderMathInText = function renderMathInText(text, optionsCopy) { var data = splitAtDelimiters(text, optionsCopy.delimiters); if (data.length === 1 && data[0].type === 'text') { // There is no formula in the text. // Let's return null which means there is no need to replace // the current text node with a new one. return null; } var fragment = document.createDocumentFragment(); for (var i = 0; i < data.length; i++) { if (data[i].type === "text") { fragment.appendChild(document.createTextNode(data[i].data)); } else { var span = document.createElement("span"); var math = data[i].data; // Override any display mode defined in the settings with that // defined by the text itself optionsCopy.displayMode = data[i].display; try { if (optionsCopy.preProcess) { math = optionsCopy.preProcess(math); } katex.render(math, span, optionsCopy); } catch (e) { if (!(e instanceof katex.ParseError)) { throw e; } optionsCopy.errorCallback("KaTeX auto-render: Failed to parse `" + data[i].data + "` with ", e); fragment.appendChild(document.createTextNode(data[i].rawData)); continue; } fragment.appendChild(span); } } return fragment; }; var renderElem = function renderElem(elem, optionsCopy) { for (var i = 0; i < elem.childNodes.length; i++) { var childNode = elem.childNodes[i]; if (childNode.nodeType === 3) { // Text node var frag = renderMathInText(childNode.textContent, optionsCopy); if (frag) { i += frag.childNodes.length - 1; elem.replaceChild(frag, childNode); } } else if (childNode.nodeType === 1) { (function () { // Element node var className = ' ' + childNode.className + ' '; var shouldRender = optionsCopy.ignoredTags.indexOf(childNode.nodeName.toLowerCase()) === -1 && optionsCopy.ignoredClasses.every(x => className.indexOf(' ' + x + ' ') === -1); if (shouldRender) { renderElem(childNode, optionsCopy); } })(); } // Otherwise, it's something else, and ignore it. } }; var renderMathInElement = function renderMathInElement(elem, options) { if (!elem) { throw new Error("No element provided to render"); } var optionsCopy = {}; // Object.assign(optionsCopy, option) for (var option in options) { if (options.hasOwnProperty(option)) { optionsCopy[option] = options[option]; } } // default options optionsCopy.delimiters = optionsCopy.delimiters || [{ left: "$$", right: "$$", display: true }, { left: "\\(", right: "\\)", display: false }, // LaTeX uses $…$, but it ruins the display of normal `$` in text: // {left: "$", right: "$", display: false}, // $ must come after $$ // Render AMS environments even if outside $$…$$ delimiters. { left: "\\begin{equation}", right: "\\end{equation}", display: true }, { left: "\\begin{align}", right: "\\end{align}", display: true }, { left: "\\begin{alignat}", right: "\\end{alignat}", display: true }, { left: "\\begin{gather}", right: "\\end{gather}", display: true }, { left: "\\begin{CD}", right: "\\end{CD}", display: true }, { left: "\\[", right: "\\]", display: true }]; optionsCopy.ignoredTags = optionsCopy.ignoredTags || ["script", "noscript", "style", "textarea", "pre", "code", "option"]; optionsCopy.ignoredClasses = optionsCopy.ignoredClasses || []; optionsCopy.errorCallback = optionsCopy.errorCallback || console.error; // Enable sharing of global macros defined via `\gdef` between different // math elements within a single call to `renderMathInElement`. optionsCopy.macros = optionsCopy.macros || {}; renderElem(elem, optionsCopy); }; export default renderMathInElement;