diff --git a/tests/core/pistringTest.cpp b/tests/core/pistringTest.cpp
index 981e373b..7a0980c0 100644
--- a/tests/core/pistringTest.cpp
+++ b/tests/core/pistringTest.cpp
@@ -81,36 +81,6 @@ TEST(PIString_Tests, operator_concatenation_pistring_zero_zero) {
 	ASSERT_EQ(str1, "");
 }
 
-TEST(PIString_Tests, operator_concatenation_piByteArray) {
-	PIString str1 = "AB C";
-	PIByteArray str2;
-	str2.append('g');
-	str1 += str2;
-	ASSERT_EQ(str1, "AB Cg");
-}
-
-TEST(PIString_Tests, operator_concatenation_piByteArray_zero1) {
-	PIString str1 = "";
-	PIByteArray str2;
-	str2.append('0');
-	str1 += str2;
-	ASSERT_EQ(str1, "0");
-}
-
-TEST(PIString_Tests, operator_concatenation_piByteArray_zero2) {
-	PIString str1 = "AB C";
-	PIByteArray str2;
-	str1 += str2;
-	ASSERT_EQ(str1, "AB C");
-}
-
-TEST(PIString_Tests, operator_concatenation_piByteArray_zero_zero) {
-	PIString str1;
-	PIByteArray str2;
-	str1 += str2;
-	ASSERT_EQ(str1, "");
-}
-
 TEST(PIString_Tests, construct_pistring) {
 	PIString str1 = "New";
 	PIString str(str1);
@@ -152,7 +122,7 @@ TEST(PIString_Tests, construct_from_pibyte_array) {
 	PIByteArray str1;
 	str1.append('m');
 	PIString res = "m";
-	ASSERT_EQ(res, PIString(str1));
+	ASSERT_EQ(res, PIString::fromUTF8(str1));
 }
 
 TEST(PIString_Tests, construct_from_pichar_array) {