code: function peakLeakPoint(jsHeapSnapShot, rootIndex, limit) {
          limit = limit || 5;
          let retainedSizeList = jsHeapSnapShot._retainedSizes;
          let root = heapNodeSerialize(jsHeapSnapShot, rootIndex);
          let strongRoots = null;
          for (let i = 0, e = root.children, l = e.length; i < l; i++) {
              const edgeType = e[i].type;
              if (edgeType === 'shortcut') {
                  continue;
              }
              if (!strongRoots) {
                  strongRoots = heapNodeSerialize(jsHeapSnapShot, e[i].index);
              }
          }
  
          let nodeToRootType = new Map();
          strongRoots.children.forEach(edge => {
              let node = heapNodeSerialize(jsHeapSnapShot, edge.index);
              let name = node.name;
              let ngr = true;
              if (!HeapNodeType[name]) {
                  ngr = HeapNodeType[''].not_gc_root;
              } else {
                  ngr = HeapNodeType[name].not_gc_root;
              }
              if (!ngr) {
                  nodeToRootType.set(node, HeapNodeType[name] || HeapNodeType['']);
              }
          });
  
          let gcRootsList = [];
          nodeToRootType.forEach((v, k) => {
              k.children.forEach(e => {
                  let node = heapNodeSerialize(jsHeapSnapShot, e.index);
                  if (e.type === 'shortcut' || node.type === 'synthetic') {
                      throw new Error('v8 heapsnapshot parser error')
                  }
                  if (e.type === 'weak') {
                      return;
                  }
                  let rootName = null;
                  // TODO: null_value 和 the_hole_value 后续处理
                  gcRootsList.push({
                      index: node.index,
                      size: node.retainedSize
                  });
              });
          });
  
          // 计算疑似泄漏点
          let leakPoint = gcRootsList.sort((o, n) => o.size < n.size ? 1 : -1).filter((g, i) => i < limit);
          return leakPoint
      }
docs: 获取疑似泄漏点