From 038e02d8d9d35d0734c1c522dec8a74d90486825 Mon Sep 17 00:00:00 2001
From: zitan <11285749+gg814@users.noreply.github.com>
Date: Mon, 1 Jun 2020 12:13:36 -0700
Subject: [PATCH] Remove extraneous newline from ldb stderr (#6897)

Summary:
**Summary**
Remove the extraneous newline when using ldb tool. For example, the subcommand list_column_families will print an empty line to stderr even if there are no errors.

**Test plan**
Passed make check; manually tested a few ldb subcommands.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6897

Reviewed By: pdillinger

Differential Revision: D21819352

Pulled By: gg814

fbshipit-source-id: 5a16a6431bb96684fe97647f4d3ac5bf0ec7fc90
---
 tools/ldb_tool.cc | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/tools/ldb_tool.cc b/tools/ldb_tool.cc
index 80e71b35f..f9374955a 100644
--- a/tools/ldb_tool.cc
+++ b/tools/ldb_tool.cc
@@ -124,7 +124,9 @@ int LDBCommandRunner::RunCommand(
 
   cmdObj->Run();
   LDBCommandExecuteResult ret = cmdObj->GetExecuteState();
-  fprintf(stderr, "%s\n", ret.ToString().c_str());
+  if (!ret.ToString().empty()) {
+    fprintf(stderr, "%s\n", ret.ToString().c_str());
+  }
   delete cmdObj;
 
   return ret.IsFailed() ? 1 : 0;