#3192 Adding the ability to create invisible links in flowcharts(v2)

Author: knsv

packages/mermaid/src/dagre-wrapper/edges.js

@@ -438,6 +438,9 @@ export const insertEdge = function (elem, e, edge, clusterDb, diagramType, graph
     case 'thick':
       strokeClasses = 'edge-thickness-thick';
       break;
+    case 'invisible':
+      strokeClasses = 'edge-thickness-thick';
+      break;
     default:
       strokeClasses = '';
   }

packages/mermaid/src/diagrams/flowchart/flowDb.js

@@ -674,6 +674,10 @@ const destructEndLink = (_str) => {
     stroke = 'thick';
   }
 
+  if (line[0] === '~') {
+    stroke = 'invisible';
+  }
+
   let dots = countChar('.', line);
 
   if (dots) {

packages/mermaid/src/diagrams/flowchart/flowRenderer-v2.js

@@ -280,6 +280,11 @@ export const addEdges = function (edges, g, diagObj) {
         edgeData.pattern = 'solid';
         edgeData.style = 'stroke-width: 3.5px;fill:none;';
         break;
+      case 'invisible':
+        edgeData.thickness = 'invisible';
+        edgeData.pattern = 'solid';
+        edgeData.style = 'stroke-width: 0;fill:none;';
+        break;
     }
     if (typeof edge.style !== 'undefined') {
       const styles = getStylesFromArray(edge.style);

packages/mermaid/src/diagrams/flowchart/parser/flow.jison

@@ -120,6 +120,7 @@ that id.
 \s*[xo<]?\-\-+[-xo>]\s*     return 'LINK';
 \s*[xo<]?\=\=+[=xo>]\s*     return 'LINK';
 \s*[xo<]?\-?\.+\-[xo>]?\s*  return 'LINK';
+\s*\~\~[\~]+\s*  return 'LINK';
 \s*[xo<]?\-\-\s*            return 'START_LINK';
 \s*[xo<]?\=\=\s*            return 'START_LINK';
 \s*[xo<]?\-\.\s*            return 'START_LINK';