perf: Added utilities::caseInsensitiveLess. (#882)

* Added utilities::caseInsensitiveLess to compare two wstring arguments
* Replaced less comparision method in DummyNodeComp.
* Added tests for caseInsensitiveLess.

src/lib/component/controller/helper/DummyNode.h

@@ -40,7 +40,7 @@ public:
 				return a->isBundleNode();
 			}
 
-			return utility::toLowerCase(a->name) < utility::toLowerCase(b->name);
+			return utility::caseInsensitiveLess(a->name, b->name);
 		}
 	};
 

src/lib_utility/utility/utilityString.cpp

@@ -622,4 +622,27 @@ std::wstring convertWhiteSpacesToSingleSpaces(const std::wstring& str)
 
 	return join<std::deque<std::wstring>>(parts, L" ");
 }
+
+bool caseInsensitiveLess(const std::wstring& s1, const std::wstring& s2)
+{
+	size_t s1_size = s1.size();
+	size_t s2_size = s2.size();
+	bool res_cmp = s1_size < s2_size; 
+	size_t lesser_size = s2_size ^ ((s1_size ^ s2_size) & -res_cmp);
+	for (size_t i = 0; i < lesser_size; ++i)
+	{
+		wchar_t s1_wchr = s1[i];
+		wchar_t s2_wchr = s2[i];
+		if (s1_wchr != s2_wchr)
+		{
+			s1_wchr = towlower(s1_wchr);
+			s2_wchr = towlower(s2_wchr);
+			if (s1_wchr != s2_wchr)
+			{
+				return s1_wchr < s2_wchr;
+			}
+		}
+	}
+	return res_cmp;
+}
 }	 // namespace utility

src/lib_utility/utility/utilityString.h

@@ -99,6 +99,8 @@ std::wstring elide(const std::wstring& str, ElideMode mode, size_t size);
 
 std::wstring convertWhiteSpacesToSingleSpaces(const std::wstring& str);
 
+bool caseInsensitiveLess(const std::wstring& s1, const std::wstring& s2);
+
 template <typename ContainerType>
 ContainerType split(const std::string& str, const std::string& delimiter)
 {

src/test/UtilityStringTestSuite.cpp

@@ -300,3 +300,69 @@ TEST_CASE("replace")
 	REQUIRE("" == utility::replace("", "foo", "bar"));
 	REQUIRE("foobar" == utility::replace("foobar", "ba", "ba"));
 }
+
+TEST_CASE("caseInsensitiveLess should return false when comparing empty wstrings")
+{
+	REQUIRE_FALSE(utility::caseInsensitiveLess(L"", L""));
+}
+
+TEST_CASE("caseInsensitiveLess should return false when both wstrings are equal")
+{
+	REQUIRE_FALSE(utility::caseInsensitiveLess(L"ab_cd!", L"ab_cd!"));
+}
+
+TEST_CASE("caseInsensitiveLess should return false when both wstrings have"
+		"different cases but after lower casing are equal")
+{
+	REQUIRE_FALSE(utility::caseInsensitiveLess(L"ab_CD!", L"aB_cD!"));
+}
+
+TEST_CASE("caseInsensitiveLess should return true when first wstring is empty and second not")
+{
+	REQUIRE(utility::caseInsensitiveLess(L"", L"ab"));
+}
+
+TEST_CASE("caseInsensitiveLess should return false when second wstring is empty and first not")
+{
+	REQUIRE_FALSE(utility::caseInsensitiveLess(L"ab", L""));
+}
+
+TEST_CASE("caseInsensitiveLess should return true when first wstring is prefix of second")
+{
+	REQUIRE(utility::caseInsensitiveLess(L"ab_cd!", L"ab_cd!e"));
+}
+
+TEST_CASE("caseInsensitiveLess should return false when second wstring is prefix of first")
+{
+	REQUIRE_FALSE(utility::caseInsensitiveLess(L"ab_cd!e", L"ab_cd!"));
+}
+
+TEST_CASE("caseInsensitiveLess should return true when after lower casing first wstring, first is prefix of second")
+{
+	REQUIRE(utility::caseInsensitiveLess(L"aB_cd!", L"ab_cd!e"));
+}
+
+TEST_CASE("caseInsensitiveLess should return true when after lower casing second wstring, first is prefix of second")
+{
+	REQUIRE(utility::caseInsensitiveLess(L"ab_cd!", L"ab_cD!e"));
+}
+
+TEST_CASE("caseInsensitiveLess should return true when after lower casing both wstrings, first is prefix of second")
+{
+	REQUIRE(utility::caseInsensitiveLess(L"aB_cd!", L"ab_cD!E"));
+}
+
+TEST_CASE("caseInsensitiveLess should return false when after lower casing first wstring, second is prefix of first")
+{
+	REQUIRE_FALSE(utility::caseInsensitiveLess(L"ab_Cd!e", L"ab_cd!"));
+}
+
+TEST_CASE("caseInsensitiveLess should return false when after lower casing second wstring, second is prefix of first")
+{
+	REQUIRE_FALSE(utility::caseInsensitiveLess(L"ab_cd!e", L"Ab_cd!"));
+}
+
+TEST_CASE("caseInsensitiveLess should return false when after lower casing both wstrings, second is prefix of first")
+{
+	REQUIRE_FALSE(utility::caseInsensitiveLess(L"ab_cD!E", L"aB_cd!"));
+}