[ui5-builder][INTERNAL] JSDoc generation: enable links with prefix 'demo:' (#743)

Allows using the following JSDoc syntax {@link demo:my/module/page/demo.html My Demo}

Author: flovogt

packages/builder/lib/processors/jsdoc/lib/transformApiJson.js

@@ -1386,13 +1386,16 @@ function transformer(sInputFile, sOutputFile, sLibraryFile, vDependencyAPIFiles,
 
 		},
 
+		formatUrlToLink: function(sTarget, sText, bSAPHosted){
+			return `<a target="_blank" rel="noopener noreferrer" href="${sTarget}">${sText}</a>
+			<img src="./resources/sap/ui/documentation/sdk/images/${bSAPHosted ? 'link-sap' : 'link-external'}.png"
+			title="Information published on ${bSAPHosted ? '' : 'non '}SAP site" class="sapUISDKExternalLink"/>`;
+		},
+
 		handleExternalUrl: function (sTarget, sText) {
 			// Check if the external domain is SAP hosted
 			let bSAPHosted = /^https?:\/\/([\w.]*\.)?(?:sap|hana\.ondemand|sapfioritrial)\.com/.test(sTarget);
-
-			return `<a target="_blank" rel="noopener noreferrer" href="${sTarget}">${sText}</a>
-<img src="./resources/sap/ui/documentation/sdk/images/${bSAPHosted ? 'link-sap' : 'link-external'}.png"
-title="Information published on ${bSAPHosted ? '' : 'non '}SAP site" class="sapUISDKExternalLink"/>`;
+			return this.formatUrlToLink(sTarget, sText, bSAPHosted);
 		},
 
 		/**
@@ -1599,6 +1602,12 @@ title="Information published on ${bSAPHosted ? '' : 'non '}SAP site" class="sapU
 							return '<a target="_self" href="topic/' + aMatch[1] + '">' + sText + '</a>';
 						}
 
+						// demo:xxx Demo, open the demonstration page in a new window
+						aMatch = sTarget.match(/^demo:([a-zA-Z0-9\/.]*)$/);
+						if (aMatch) {
+							return this.formatUrlToLink("test-resources/" + aMatch[1], sText, true);
+						}
+
 						// sap.x.Xxx.prototype.xxx - In case of prototype we have a link to method
 						aMatch = sTarget.match(/([a-zA-Z0-9.$_]+?)\.prototype\.([a-zA-Z0-9.$_]+)$/);
 						if (aMatch) {