add buildCallsPath to Util

src/helpers/util.js

@@ -85,7 +85,21 @@ module.exports = {
     return index >= 0 ? array[index] : null
   },
 
-  findCall: findCall
+  findCall: findCall,
+  buildCallsPath: buildCallsPath
+}
+
+/**
+  * Find calls path from @args rootCall which leads to @args index (recursive)
+  *
+  * @param {Int} index - index of the vmtrace
+  * @param {Object} rootCall  - call tree, built by the trace analyser
+  * @return {Array} - return the calls path to @args index
+  */
+function buildCallsPath (index, rootCall) {
+  var ret = []
+  findCallInternal(index, rootCall, ret)
+  return ret
 }
 
 /**
@@ -96,12 +110,18 @@ module.exports = {
   * @return {Object} - return the call which include the @args index
   */
 function findCall (index, rootCall) {
+  var ret = buildCallsPath(index, rootCall)
+  return ret[ret.length - 1]
+}
+
+function findCallInternal (index, rootCall, callsPath) {
   var calls = Object.keys(rootCall.calls)
   var ret = rootCall
+  callsPath.push(rootCall)
   for (var k in calls) {
     var subCall = rootCall.calls[calls[k]]
     if (index >= subCall.start && index <= subCall.return) {
-      ret = findCall(index, subCall)
+      findCallInternal(index, subCall, callsPath)
       break
     }
   }

src/trace/traceManager.js

@@ -114,6 +114,16 @@ TraceManager.prototype.getCallDataAt = function (stepIndex, callback) {
   callback(null, [this.traceCache.callsData[callDataChange]])
 }
 
+TraceManager.prototype.buildCallsPath = function (stepIndex, callback) {
+  var check = this.checkRequestedStep(stepIndex)
+  if (check) {
+    return callback(check, null)
+  }
+  var callsPath = util.buildCallsPath(stepIndex, this.traceCache.callsTree.call)
+  if (callsPath === null) return callback('no call path built', null)
+  callback(null, callsPath)
+}
+
 TraceManager.prototype.getCallStackAt = function (stepIndex, callback) {
   var check = this.checkRequestedStep(stepIndex)
   if (check) {