Correct pathing

lib/src/helper/traverser.ts

@@ -110,6 +110,39 @@ export default class Traverser {
         return current;
     }
 
+    /**
+     * Traverse donwards from a start element by using a path.
+     * @param start Start element
+     * @param path a JS-linke path, eg. map.entry.list[0].property
+     * @returns Target element at the end of the path or null if not found
+     * @public
+     */
+    public static traverseByPath(start: types.Class, path: string): types.Class | null {
+        const ids = path.split(".");
+        let current: types.Class | null = start;
+        const regex = /(\[\d+\])+$/i
+
+        for (const idShort of ids) {
+            if (!idShort) continue;
+            if (current === null) return null;
+
+            current = Traverser.findChildByIdShort(current, idShort);
+            const match = regex.exec(idShort)?.[0];
+            if (match) {
+                const indexes = match.split("][").map(index => parseInt(index.replace("[", "").replace("]", "")));
+
+                for (const index of indexes) {
+                    if (current === null || !types.isSubmodelElementList(current) || current.value === null) return null;
+                    const next = current.value?.at(index);
+                    if (next === undefined) return null;
+                    current = next;
+                }
+            }
+        }
+
+        return current;
+    }
+
     /**
      * Get element by using idShorts from an submodel.
      * @param env Environment to search in
@@ -124,6 +157,20 @@ export default class Traverser {
         return Traverser.traverseByShortIds(sm, idShorts);
     }
 
+    /**
+     * Get element by using a path from an submodel.
+     * @param env Environment to search in
+     * @param submodelOrIdShort Submodel element or Submodel idShort
+     * @param path path to traverse by
+     * @returns Target element at the end of the path or null if not found
+     * @public
+     */
+    public static getElementByPath(env: types.Environment, submodelOrIdShort: string | types.Submodel, path: string): types.Class | null {
+        const sm = typeof submodelOrIdShort === "string" ? Traverser.findSMByIdShort(env, submodelOrIdShort) : submodelOrIdShort;
+        if (sm === null) return null;
+        return Traverser.traverseByPath(sm, path);
+    }
+
     /**
      * Find an element using a function to check.
      * @param start Start element