Update KaTeX wrapper to support operation under Node.js

Now we can generate static HTML containing mathematical typesetting

core/modules/utils/fakedom.js

@@ -143,7 +143,9 @@ Object.defineProperty(TW_Element.prototype, "outerHTML", {
 			for(var s in this.style) {
 				style.push(s + ":" + this.style[s] + ";");
 			}
-			output.push(" style='",style.join(""),"'")
+			if(style.length > 0) {
+				output.push(" style='",style.join(""),"'")
+			}
 		}
 		output.push(">");
 		if($tw.config.htmlVoidElements.indexOf(this.tag) === -1) {

editions/katexdemo/tiddlers/HelloThere.tid

@@ -2,9 +2,7 @@ title: HelloThere
 
 This is a TiddlyWiki plugin for mathematical typesetting based on KaTeX from Khan Academy.
 
-It is completely self-contained, and doesn't need an Internet connection in order to work.
-
-//This first version of the plugin cannot be used to generate static content under Node.js, but that capability will come in a future update. (Note that you can still use it when running the client-server configuration under Node.js).//
+It is completely self-contained, and doesn't need an Internet connection in order to work. It works both in the browser and under Node.js.
 
 ! Installation
 

editions/katexdemo/tiddlywiki.info

@@ -10,6 +10,11 @@
 	],
 	"build": {
 		"index": [
-			"--rendertiddler","$:/core/save/all","katexdemo.html","text/plain"]
+			"--rendertiddler","$:/core/save/all","katexdemo.html","text/plain"],
+		"static": [
+			"--rendertiddler","$:/core/templates/static.template.html","static.html","text/plain",
+			"--rendertiddler","$:/core/templates/alltiddlers.template.html","alltiddlers.html","text/plain",
+			"--rendertiddlers","[!is[system]]","$:/core/templates/static.tiddler.html","static","text/plain",
+			"--rendertiddler","$:/core/templates/static.template.css","static/static.css","text/plain"]
 	}
 }

plugins/tiddlywiki/katex/files/tiddlywiki.files

@@ -78,7 +78,9 @@
 				"type": "application/javascript",
 				"title": "$:/plugins/tiddlywiki/katex/katex.min.js",
 				"module-type": "library"
-			}
+			},
+			"prefix": "(function(document) {\n",
+			"suffix": "\n})($tw.node ? $tw.fakeDocument : window.document)\n"
 		}
 	]
 }

plugins/tiddlywiki/katex/wrapper.js

@@ -37,7 +37,11 @@ KaTeXWidget.prototype.render = function(parent,nextSibling) {
 	// Render it into a span
 	var span = this.document.createElement("span");
 	try {
-		katex.render(text,span);
+		if($tw.browser) {
+			katex.render(text,span);
+		} else {
+			span.innerHTML = katex.renderToString(text);
+		}
 	} catch(ex) {
 		span.className = "tc-error";
 		span.textContent = ex;