need to fix mocktikv

store/copr/coprocessor.go

@@ -77,12 +77,9 @@ func (c *CopClient) Send(ctx context.Context, req *kv.Request, variables interfa
 	if !ok {
 		return copErrorResponse{errors.Errorf("unsupported variables:%+v", variables)}
 	}
-	if req.StoreType == kv.TiFlash {
-		if req.BatchCop {
-			logutil.BgLogger().Debug("send batch requests")
-			return c.sendBatch(ctx, req, vars, option)
-		}
-		req.Paging = false
+	if req.StoreType == kv.TiFlash && req.BatchCop {
+		logutil.BgLogger().Debug("send batch requests")
+		return c.sendBatch(ctx, req, vars, option)
 	}
 	failpoint.Inject("DisablePaging", func(_ failpoint.Value) {
 		req.Paging = false
@@ -863,7 +860,9 @@ func (worker *copIteratorWorker) handleCopPagingResult(bo *Backoffer, rpcCtx *ti
 	pagingRange := resp.pbResp.Range
 	// only paging requests need to calculate the next ranges
 	if pagingRange == nil {
-		return nil, errors.New("lastRange in paging should not be nil")
+		// If the storage engine doesn't support paging protocol, it should have return all the region data.
+		// So we finish here.
+		return nil, nil
 	}
 	// calculate next ranges and grow the paging size
 	task.ranges = worker.calculateRemain(task.ranges, pagingRange, worker.req.Desc)