Cleanup JSONP highlight code (#1674)

Document, refactor and format the JSONP Highlighting plugin.

Author: RunDevelopment

plugins/jsonp-highlight/prism-jsonp-highlight.js

@@ -1,136 +1,167 @@
-(function() {
-	if ( !self.Prism || !self.document || !document.querySelectorAll || ![].filter) return;
+(function () {
+	if (!self.Prism || !self.document || !document.querySelectorAll || ![].filter) return;
 
+	/**
+	 * The list of adapter which will be used if `data-adapter` is not specified.
+	 *
+	 * @type {Array.<(response: any, pre?: HTMLPreElement) => string>}
+	 */
 	var adapters = [];
+
+	/**
+	 * Adds a new function to the list of adapters.
+	 *
+	 * If the given adapter is already registered or not a function, nothing will happen.
+	 *
+	 * @param {(response: any, pre?: HTMLPreElement) => string} adapter The adapter to be registered.
+	 */
 	function registerAdapter(adapter) {
 		if (typeof adapter === "function" && !getAdapter(adapter)) {
 			adapters.push(adapter);
 		}
 	}
+	/**
+	 * Returns the given adapter itself, if registered, or a registered adapter with the given function name.
+	 *
+	 * If no fitting adapter is registered, `null` will be returned.
+	 *
+	 * @param {string|Function} adapter The adapter itself or the function name of an adapter.
+	 * @returns {(response: any, pre?: HTMLPreElement) => string} A registered adapter or `null`.
+	 */
 	function getAdapter(adapter) {
 		if (typeof adapter === "function") {
-			return adapters.filter(function(fn) { return fn.valueOf() === adapter.valueOf()})[0];
+			return adapters.filter(function (fn) { return fn.valueOf() === adapter.valueOf(); })[0];
 		}
 		else if (typeof adapter === "string" && adapter.length > 0) {
-			return adapters.filter(function(fn) { return fn.name === adapter})[0];
+			return adapters.filter(function (fn) { return fn.name === adapter; })[0];
 		}
 		return null;
 	}
+	/**
+	 * Remove the given adapter or the first registered adapter with the given function name from the list of
+	 * registered adapters.
+	 *
+	 * @param {string|Function} adapter The adapter itself or the function name of an adapter.
+	 */
 	function removeAdapter(adapter) {
-		if (typeof adapter === "string")
+		if (typeof adapter === "string") {
 			adapter = getAdapter(adapter);
+		}
 		if (typeof adapter === "function") {
 			var index = adapters.indexOf(adapter);
-			if (index >=0) {
-				adapters.splice(index,1);
+			if (index >= 0) {
+				adapters.splice(index, 1);
 			}
 		}
 	}
 
-	Prism.plugins.jsonphighlight = {
-		registerAdapter: registerAdapter,
-		removeAdapter: removeAdapter,
-		highlight: highlight
-	};
 	registerAdapter(function github(rsp, el) {
-		if ( rsp && rsp.meta && rsp.data ) {
-			if ( rsp.meta.status && rsp.meta.status >= 400 ) {
-				return "Error: " + ( rsp.data.message || rsp.meta.status );
+		if (rsp && rsp.meta && rsp.data) {
+			if (rsp.meta.status && rsp.meta.status >= 400) {
+				return "Error: " + (rsp.data.message || rsp.meta.status);
 			}
-			else if ( typeof(rsp.data.content) === "string" ) {
-				return typeof(atob) === "function"
+			else if (typeof (rsp.data.content) === "string") {
+				return typeof (atob) === "function"
 					? atob(rsp.data.content.replace(/\s/g, ""))
 					: "Your browser cannot decode base64";
 			}
 		}
 		return null;
 	});
 	registerAdapter(function gist(rsp, el) {
-		if ( rsp && rsp.meta && rsp.data && rsp.data.files ) {
-			if ( rsp.meta.status && rsp.meta.status >= 400 ) {
-				return "Error: " + ( rsp.data.message || rsp.meta.status );
+		if (rsp && rsp.meta && rsp.data && rsp.data.files) {
+			if (rsp.meta.status && rsp.meta.status >= 400) {
+				return "Error: " + (rsp.data.message || rsp.meta.status);
 			}
-			else {
-				var filename = el.getAttribute("data-filename");
-				if (filename == null) {
-					// Maybe in the future we can somehow render all files
-					// But the standard <script> include for gists does that nicely already,
-					// so that might be getting beyond the scope of this plugin
-					for (var key in rsp.data.files) {
-						if (rsp.data.files.hasOwnProperty(key)) {
-							filename = key;
-							break;
-						}
+
+			var files = rsp.data.files;
+			var filename = el.getAttribute("data-filename");
+			if (filename == null) {
+				// Maybe in the future we can somehow render all files
+				// But the standard <script> include for gists does that nicely already,
+				// so that might be getting beyond the scope of this plugin
+				for (var key in files) {
+					if (files.hasOwnProperty(key)) {
+						filename = key;
+						break;
 					}
 				}
-				if (rsp.data.files[filename] !== undefined) {
-					return rsp.data.files[filename].content;
-				}
-				else {
-					return "Error: unknown or missing gist file " + filename;
-				}
 			}
+
+			if (files[filename] !== undefined) {
+				return files[filename].content;
+			}
+			return "Error: unknown or missing gist file " + filename;
 		}
 		return null;
 	});
 	registerAdapter(function bitbucket(rsp, el) {
-		return rsp && rsp.node && typeof(rsp.data) === "string"
-			? rsp.data
-			: null;
+		if (rsp && rsp.node && typeof (rsp.data) === "string") {
+			return rsp.data;
+		}
+		return null;
 	});
 
 	var jsonpcb = 0,
-	    loadstr = "Loading…";
+		loadMsg = "Loading\u2026";
 
+	/**
+	 * Highlights all `pre` elements with an `data-jsonp` by requesting the specified JSON and using the specified adapter
+	 * or a registered adapter to extract the code to highlight from the response. The highlighted code will be inserted
+	 * into the `pre` element.
+	 */
 	function highlight() {
-		Array.prototype.slice.call(document.querySelectorAll("pre[data-jsonp]")).forEach(function(pre) {
+		Array.prototype.slice.call(document.querySelectorAll("pre[data-jsonp]")).forEach(function (pre) {
 			pre.textContent = "";
 
 			var code = document.createElement("code");
-			code.textContent = loadstr;
+			code.textContent = loadMsg;
 			pre.appendChild(code);
 
-			var adapterfn = pre.getAttribute("data-adapter");
+			var adapterName = pre.getAttribute("data-adapter");
 			var adapter = null;
-			if ( adapterfn ) {
-				if ( typeof(window[adapterfn]) === "function" ) {
-					adapter = window[adapterfn];
+			if (adapterName) {
+				if (typeof window[adapterName] === "function") {
+					adapter = window[adapterName];
 				}
 				else {
-					code.textContent = "JSONP adapter function '" + adapterfn + "' doesn't exist";
+					code.textContent = "JSONP adapter function '" + adapterName + "' doesn't exist";
 					return;
 				}
 			}
 
-			var cb = "prismjsonp" + ( jsonpcb++ );
-			
+			var cb = "prismjsonp" + jsonpcb++;
+
 			var uri = document.createElement("a");
 			var src = uri.href = pre.getAttribute("data-jsonp");
-			uri.href += ( uri.search ? "&" : "?" ) + ( pre.getAttribute("data-callback") || "callback" ) + "=" + cb;
+			uri.href += (uri.search ? "&" : "?") + (pre.getAttribute("data-callback") || "callback") + "=" + cb;
 
-			var timeout = setTimeout(function() {
+			var timeout = setTimeout(function () {
 				// we could clean up window[cb], but if the request finally succeeds, keeping it around is a good thing
-				if ( code.textContent === loadstr )
+				if (code.textContent === loadMsg) {
 					code.textContent = "Timeout loading '" + src + "'";
+				}
 			}, 5000);
-			
+
 			var script = document.createElement("script");
 			script.src = uri.href;
 
-			window[cb] = function(rsp) {
+			window[cb] = function (rsp) {
 				document.head.removeChild(script);
 				clearTimeout(timeout);
 				delete window[cb];
 
 				var data = "";
-				
-				if ( adapter ) {
+
+				if (adapter) {
 					data = adapter(rsp, pre);
 				}
 				else {
-					for ( var p in adapters ) {
+					for (var p in adapters) {
 						data = adapters[p](rsp, pre);
-						if ( data !== null ) break;
+						if (data !== null) {
+							break;
+						}
 					}
 				}
 
@@ -147,5 +178,11 @@
 		});
 	}
 
+	Prism.plugins.jsonphighlight = {
+		registerAdapter: registerAdapter,
+		removeAdapter: removeAdapter,
+		highlight: highlight
+	};
+
 	highlight();
 })();