From f916f46b0153b1ebccd2d02a9e5a541c9e9c0959 Mon Sep 17 00:00:00 2001
From: Martin Jobst <martin.jobst@posteo.de>
Date: Thu, 21 Mar 2024 17:33:25 +0100
Subject: [PATCH] Add missing STRING_TO_CHAR function

---
 src/core/datatypes/convert/StringToConvertFunctions.h   | 4 ++++
 tests/core/datatypes/convert/convert_functionstests.cpp | 8 +++++++-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/src/core/datatypes/convert/StringToConvertFunctions.h b/src/core/datatypes/convert/StringToConvertFunctions.h
index 61d95c10b..074c617c4 100644
--- a/src/core/datatypes/convert/StringToConvertFunctions.h
+++ b/src/core/datatypes/convert/StringToConvertFunctions.h
@@ -96,6 +96,10 @@ inline const CIEC_LREAL func_STRING_AS_LREAL(const CIEC_STRING &paVal){
   return func_STRING_AS_X_helper<CIEC_LREAL>(paVal);
 }
 
+inline const CIEC_CHAR func_STRING_TO_CHAR(const CIEC_STRING &paVal){
+  return paVal.length() > 0 ? paVal[1] : 0_CHAR;
+}
+
 #ifdef FORTE_USE_WSTRING_DATATYPE
 inline const CIEC_WSTRING func_STRING_TO_WSTRING(const CIEC_STRING &paVal){
   return func_STRING_AS_X_helper<CIEC_WSTRING>(paVal);
diff --git a/tests/core/datatypes/convert/convert_functionstests.cpp b/tests/core/datatypes/convert/convert_functionstests.cpp
index d22ff41fb..ecc006082 100644
--- a/tests/core/datatypes/convert/convert_functionstests.cpp
+++ b/tests/core/datatypes/convert/convert_functionstests.cpp
@@ -427,7 +427,13 @@ BOOST_AUTO_TEST_SUITE(convert_functions)
     BOOST_TEST(
       static_cast<CIEC_LREAL::TValueType>(timeInNs) == static_cast<CIEC_LREAL::TValueType>(INT64_C(172800000000000) + INT64_C(18000000000000) + INT64_C(2580000000000) + INT64_C(12000000000) + INT64_C(44000000) + INT64_C(27000) + INT64_C(31)));
   }
-  
+
+  BOOST_AUTO_TEST_CASE(CONVERT_STRING_TO_CHAR) {
+    BOOST_TEST(static_cast<CIEC_CHAR::TValueType>(func_STRING_TO_CHAR(""_STRING)) == '\0');
+    BOOST_TEST(static_cast<CIEC_CHAR::TValueType>(func_STRING_TO_CHAR("a"_STRING)) == 'a');
+    BOOST_TEST(static_cast<CIEC_CHAR::TValueType>(func_STRING_TO_CHAR("abc"_STRING)) == 'a');
+  }
+
   /**** BYTE_BCD_TO_* ****/
   BOOST_AUTO_TEST_CASE(BYTE_BCD_TO_USINT) {
     using SourceType = CIEC_BYTE;