Merge 4d7368a01a into 2cef99c311

src/Common/DateLUT.cpp

@@ -52,6 +52,8 @@ std::string determineDefaultTimeZone()
 
         if (*tz_env_var == ':')
             ++tz_env_var;
+        else if (*tz_env_var == '\0')
+            return "UTC";
 
         tz_file_path = tz_env_var;
         tz_name = tz_env_var;
@@ -68,7 +70,7 @@ std::string determineDefaultTimeZone()
         /// Read symlink but not transitive.
         /// Example:
         ///  /etc/localtime -> /usr/share/zoneinfo//UTC
-        ///  /usr/share/zoneinfo//UTC -> UCT
+        ///  /usr/share/zoneinfo//UTC -> UTC
         /// But the preferred time zone name is pointed by the first link (UTC), and the second link is just an internal detail.
         if (FS::isSymlink(tz_file_path))
         {
@@ -89,7 +91,7 @@ std::string determineDefaultTimeZone()
             fs::path relative_path = tz_file_path.lexically_relative(tz_database_path);
 
             if (!relative_path.empty() && *relative_path.begin() != ".." && *relative_path.begin() != ".")
-                return tz_name.empty() ? relative_path.string() : tz_name;
+                return relative_path.string();
         }
 
         /// Try the same with full symlinks resolution

tests/queries/0_stateless/03206_timezone_env.reference

@@ -0,0 +1,5 @@
+UTC
+Asia/Shanghai
+Asia/Shanghai
+Europe/Amsterdam
+Poland

tests/queries/0_stateless/03206_timezone_env.sh

@@ -0,0 +1,11 @@
+#!/usr/bin/env bash
+
+CUR_DIR=$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)
+# shellcheck source=../shell_config.sh
+. "$CUR_DIR"/../shell_config.sh
+
+TZ='' ${CLICKHOUSE_LOCAL} --query "SELECT timezone()";
+TZ='Asia/Shanghai' ${CLICKHOUSE_LOCAL} --query "SELECT timezone()";
+TZ=':Asia/Shanghai' ${CLICKHOUSE_LOCAL} --query "SELECT timezone()";
+TZ=':/usr/share/zoneinfo/Europe/Amsterdam' ${CLICKHOUSE_LOCAL} --query "SELECT timezone()";
+TZ='Poland' ${CLICKHOUSE_LOCAL} --query "SELECT timezone()";