diff --git a/tests/core/pistringTest.cpp b/tests/core/pistringTest.cpp
index 8d4f3a98..70c8414b 100644
--- a/tests/core/pistringTest.cpp
+++ b/tests/core/pistringTest.cpp
@@ -274,3 +274,64 @@ TEST(PIString_Tests, operator_not_equal_cstring_false){
 	char str2[] = "test";
 	ASSERT_FALSE(str1 != str2);
 }
+
+TEST(PIString_Tests, operator_not_equal_cstring_true){
+	PIString str1 = "t";
+	char str2[] = "test";
+	ASSERT_TRUE(str1 != str2);
+}
+
+TEST(PIString_Tests, operator_less_pistring_true){
+	PIString str1 = "testin";
+	PIString str2 = "testing";
+	ASSERT_TRUE(str1 < str2);
+}
+
+TEST(PIString_Tests, operator_less_pistring_false){
+	PIString str1 = "testing";
+	PIString str2 = "testin";
+	ASSERT_FALSE(str1 < str2);
+}
+
+TEST(PIString_Tests, operator_less_pistring_false_equal){
+	PIString str1 = "testing";
+	PIString str2 = "testing";
+	ASSERT_FALSE(str1 < str2);
+}
+
+TEST(PIString_Tests, operator_less_pichar_true){
+	PIString str1 = "a";
+	PIChar str2 = "t";
+	ASSERT_TRUE(str1 < str2);
+}
+
+TEST(PIString_Tests, operator_less_pichar_false){
+	PIString str1 = "t";
+	PIChar str2 = "a";
+	ASSERT_FALSE(str1 < str2);
+}
+
+TEST(PIString_Tests, operator_less_pichar_false_equal){
+	PIString str1 = "t";
+	PIChar str2 = "t";
+	ASSERT_FALSE(str1 < str2);
+}
+
+TEST(PIString_Tests, operator_less_cstring_true){
+	PIString str1 = "a";
+	char str2[] = "t";
+	ASSERT_TRUE(str1 < str2);
+}
+
+TEST(PIString_Tests, operator_less_cstring_false){
+	PIString str1 = "t";
+	char str2[] = "a";
+	ASSERT_FALSE(str1 < str2);
+}
+
+TEST(PIString_Tests, operator_less_cstring_false_equal){
+	PIString str1 = "t";
+	char str2[] = "t";
+	ASSERT_FALSE(str1 < str2);
+}
+