fix(generic): fix generic type regex

instead of looking for single tildes, we are now looking for pairs, which avoid bugs when there is an odd number of tildes

demos/classchart.html

@@ -138,7 +138,20 @@ title: Demo Class Diagram
     Pineapple : -int leafCount()
     Pineapple : -int spikeCount()
     </pre>
+    <hr />
 
+    <pre class="mermaid">
+    classDiagram
+      class Person {
+        +Id : Guid
+        +FirstName : string
+        +LastName : string
+        -privateProperty : string
+        #ProtectedProperty : string
+        ~InternalProperty : string
+        ~AnotherInternalProperty : List~MyType~
+      }
+    </pre>
     <hr />
 
     <script src="./mermaid.js"></script>

packages/mermaid/src/diagrams/common/common.spec.js

@@ -68,5 +68,6 @@ describe('generic parser', function () {
     expect(parseGenericTypes('test ~Array~Array~string[]~~~')).toEqual(
       'test <Array<Array<string[]>>>'
     );
+    expect(parseGenericTypes('~test')).toEqual('~test');
   });
 });

packages/mermaid/src/diagrams/common/common.ts

@@ -154,11 +154,17 @@ export const evaluate = (val?: string | boolean): boolean =>
 export const parseGenericTypes = function (text: string): string {
   let cleanedText = text;
 
-  if (text.includes('~')) {
+  if (text.split('~').length - 1 >= 2) {
-    cleanedText = cleanedText.replace(/~([^~].*)/, '<$1');
+    let newCleanedText = cleanedText;
-    cleanedText = cleanedText.replace(/~([^~]*)$/, '>$1');
 
-    return parseGenericTypes(cleanedText);
+    // use a do...while loop instead of replaceAll to detect recursion
+    // e.g. Array~Array~T~~
+    do {
+      cleanedText = newCleanedText;
+      newCleanedText = cleanedText.replace(/~([^\s,:;]+)~/, '<$1>');
+    } while (newCleanedText != cleanedText);
+
+    return parseGenericTypes(newCleanedText);
   } else {
     return cleanedText;
   }