add catch on buildTree

src/util/internalCallTree.js

@@ -97,13 +97,17 @@ async function buildTree (tree, step, scopeId) {
       return { outStep: step, error: 'InternalCallTree - No source Location. ' + step }
     }
     if (sourceLocation.jump === 'i') {
+      try {
         var result = await buildTree(tree, step + 1, scopeId === '' ? subScope.toString() : scopeId + '.' + subScope)
         if (result.error) {
-        return result
+          return { outStep: step, error: 'InternalCallTree - ' + result.error }
         } else {
           step = result.outStep
           subScope++
         }
+      } catch (e) {
+        return { outStep: step, error: 'InternalCallTree - ' + e.message }
+      }
     } else if (sourceLocation.jump === 'o') {
       tree.scopes[scopeId].lastStep = step
       return { outStep: step + 1 }