From cee938fb0a627011ee1299f55020b719c3bc4e97 Mon Sep 17 00:00:00 2001
From: Tao He <sighingnow@gmail.com>
Date: Wed, 7 Apr 2021 15:07:48 +0800
Subject: [PATCH] Use UTF-8 char U+0000 as terminate charactor.

Allow setting range end as `NULL`, see also #50.

Signed-off-by: Tao He <sighingnow@gmail.com>
---
 src/v3/Action.cpp |  5 +++--
 tst/EtcdTest.cpp  | 13 ++++++++++---
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/src/v3/Action.cpp b/src/v3/Action.cpp
index 2def3ce..558e9fa 100644
--- a/src/v3/Action.cpp
+++ b/src/v3/Action.cpp
@@ -50,6 +50,7 @@ std::string etcdv3::detail::string_plus_one(std::string const &value) {
       return ret;
     }
   }
-  // see: noPrefixEnd in etcd
-  return {"\0"};
+  // see: noPrefixEnd in etcd, however c++ doesn't allows '\0' inside a string, thus we use
+  // the UTF-8 char U+0000 (i.e., "\xC0\x80").
+  return {"\xC0\x80"};
 }
diff --git a/tst/EtcdTest.cpp b/tst/EtcdTest.cpp
index a580a39..ad3d85b 100644
--- a/tst/EtcdTest.cpp
+++ b/tst/EtcdTest.cpp
@@ -231,10 +231,11 @@ TEST_CASE("list by range")
   etcd::Client etcd("http://127.0.0.1:2379");
   CHECK(0 == etcd.ls("/test/new_dir").get().keys().size());
 
+  etcd.set("/test/new_dir/key0", "value0").wait();
   etcd.set("/test/new_dir/key1", "value1").wait();
-  etcd.set("/test/new_dir/key2", "value1").wait();
-  etcd.set("/test/new_dir/key3", "value1").wait();
-  etcd.set("/test/new_dir/key4", "value1").wait();
+  etcd.set("/test/new_dir/key2", "value2").wait();
+  etcd.set("/test/new_dir/key3", "value3").wait();
+  etcd.set("/test/new_dir/key4", "value4").wait();
 
   etcd::Response resp1 = etcd.ls("/test/new_dir/key1", "/test/new_dir/key3").get();
   REQUIRE(resp1.is_ok());
@@ -248,6 +249,12 @@ TEST_CASE("list by range")
   REQUIRE(3 == resp2.keys().size());
   REQUIRE(3 == resp2.values().size());
 
+  etcd::Response resp3 = etcd.ls("/test/new_dir/key1", {"\xC0\x80"}).get();
+  REQUIRE(resp3.is_ok());
+  CHECK("get" == resp3.action());
+  REQUIRE(4 == resp3.keys().size());
+  REQUIRE(4 == resp3.values().size());
+
   CHECK(0 == etcd.ls("/test/new_dir/key1").get().error_code());
 
   CHECK(etcd.rmdir("/test/new_dir", true).get().is_ok());