diff --git a/src/ai/ai_scanner.cpp b/src/ai/ai_scanner.cpp
index dc5eab49fa..342afffb6e 100644
--- a/src/ai/ai_scanner.cpp
+++ b/src/ai/ai_scanner.cpp
@@ -123,7 +123,7 @@ AIInfo *AIScannerInfo::FindInfo(const char *nameParam, int versionParam, bool fo
 	 *  version which allows loading the requested version */
 	for (const auto &item : this->info_list) {
 		AIInfo *i = static_cast<AIInfo *>(item.second);
-		if (strcasecmp(ai_name, i->GetName()) == 0 && i->CanLoadFromVersion(versionParam) && (version == -1 || i->GetVersion() > version)) {
+		if (StrEqualsIgnoreCase(ai_name, i->GetName()) && i->CanLoadFromVersion(versionParam) && (version == -1 || i->GetVersion() > version)) {
 			version = item.second->GetVersion();
 			info = i;
 		}
diff --git a/src/blitter/factory.hpp b/src/blitter/factory.hpp
index 393b9836b7..296f6842b6 100644
--- a/src/blitter/factory.hpp
+++ b/src/blitter/factory.hpp
@@ -128,7 +128,7 @@ public:
 		Blitters::iterator it = GetBlitters().begin();
 		for (; it != GetBlitters().end(); it++) {
 			BlitterFactory *b = (*it).second;
-			if (strcasecmp(bname, b->name.c_str()) == 0) {
+			if (StrEqualsIgnoreCase(bname, b->name)) {
 				return b->IsUsable() ? b : nullptr;
 			}
 		}
diff --git a/src/console_cmds.cpp b/src/console_cmds.cpp
index b16320bbd6..6d0ca5cdf2 100644
--- a/src/console_cmds.cpp
+++ b/src/console_cmds.cpp
@@ -1868,7 +1868,7 @@ static ContentType StringToContentType(const char *str)
 {
 	static const char * const inv_lookup[] = { "", "base", "newgrf", "ai", "ailib", "scenario", "heightmap" };
 	for (uint i = 1 /* there is no type 0 */; i < lengthof(inv_lookup); i++) {
-		if (strcasecmp(str, inv_lookup[i]) == 0) return (ContentType)i;
+		if (StrEqualsIgnoreCase(str, inv_lookup[i])) return (ContentType)i;
 	}
 	return CONTENT_TYPE_END;
 }
@@ -1926,17 +1926,17 @@ DEF_CONSOLE_CMD(ConContent)
 		return true;
 	}
 
-	if (strcasecmp(argv[1], "update") == 0) {
+	if (StrEqualsIgnoreCase(argv[1], "update")) {
 		_network_content_client.RequestContentList((argc > 2) ? StringToContentType(argv[2]) : CONTENT_TYPE_END);
 		return true;
 	}
 
-	if (strcasecmp(argv[1], "upgrade") == 0) {
+	if (StrEqualsIgnoreCase(argv[1], "upgrade")) {
 		_network_content_client.SelectUpgrade();
 		return true;
 	}
 
-	if (strcasecmp(argv[1], "select") == 0) {
+	if (StrEqualsIgnoreCase(argv[1], "select")) {
 		if (argc <= 2) {
 			/* List selected content */
 			IConsolePrint(CC_WHITE, "id, type, state, name");
@@ -1944,7 +1944,7 @@ DEF_CONSOLE_CMD(ConContent)
 				if ((*iter)->state != ContentInfo::SELECTED && (*iter)->state != ContentInfo::AUTOSELECTED) continue;
 				OutputContentState(*iter);
 			}
-		} else if (strcasecmp(argv[2], "all") == 0) {
+		} else if (StrEqualsIgnoreCase(argv[2], "all")) {
 			/* The intention of this function was that you could download
 			 * everything after a filter was applied; but this never really
 			 * took off. Instead, a select few people used this functionality
@@ -1958,12 +1958,12 @@ DEF_CONSOLE_CMD(ConContent)
 		return true;
 	}
 
-	if (strcasecmp(argv[1], "unselect") == 0) {
+	if (StrEqualsIgnoreCase(argv[1], "unselect")) {
 		if (argc <= 2) {
 			IConsolePrint(CC_ERROR, "You must enter the id.");
 			return false;
 		}
-		if (strcasecmp(argv[2], "all") == 0) {
+		if (StrEqualsIgnoreCase(argv[2], "all")) {
 			_network_content_client.UnselectAll();
 		} else {
 			_network_content_client.Unselect((ContentID)atoi(argv[2]));
@@ -1971,7 +1971,7 @@ DEF_CONSOLE_CMD(ConContent)
 		return true;
 	}
 
-	if (strcasecmp(argv[1], "state") == 0) {
+	if (StrEqualsIgnoreCase(argv[1], "state")) {
 		IConsolePrint(CC_WHITE, "id, type, state, name");
 		for (ConstContentIterator iter = _network_content_client.Begin(); iter != _network_content_client.End(); iter++) {
 			if (argc > 2 && strcasestr((*iter)->name.c_str(), argv[2]) == nullptr) continue;
@@ -1980,7 +1980,7 @@ DEF_CONSOLE_CMD(ConContent)
 		return true;
 	}
 
-	if (strcasecmp(argv[1], "download") == 0) {
+	if (StrEqualsIgnoreCase(argv[1], "download")) {
 		uint files;
 		uint bytes;
 		_network_content_client.DownloadSelectedContent(files, bytes);
@@ -2007,7 +2007,7 @@ DEF_CONSOLE_CMD(ConFont)
 
 	FontSize argfs;
 	for (argfs = FS_BEGIN; argfs < FS_END; argfs++) {
-		if (argc > 1 && strcasecmp(argv[1], FontSizeToName(argfs)) == 0) break;
+		if (argc > 1 && StrEqualsIgnoreCase(argv[1], FontSizeToName(argfs))) break;
 	}
 
 	/* First argument must be a FontSize. */
@@ -2021,7 +2021,7 @@ DEF_CONSOLE_CMD(ConFont)
 
 		byte arg_index = 2;
 		/* We may encounter "aa" or "noaa" but it must be the last argument. */
-		if (strcasecmp(argv[arg_index], "aa") == 0 || strcasecmp(argv[arg_index], "noaa") == 0) {
+		if (StrEqualsIgnoreCase(argv[arg_index], "aa") || StrEqualsIgnoreCase(argv[arg_index], "noaa")) {
 			aa = strncasecmp(argv[arg_index++], "no", 2) != 0;
 			if (argc > arg_index) return false;
 		} else {
@@ -2043,7 +2043,7 @@ DEF_CONSOLE_CMD(ConFont)
 
 		if (argc > arg_index) {
 			/* Last argument must be "aa" or "noaa". */
-			if (strcasecmp(argv[arg_index], "aa") != 0 && strcasecmp(argv[arg_index], "noaa") != 0) return false;
+			if (!StrEqualsIgnoreCase(argv[arg_index], "aa") && !StrEqualsIgnoreCase(argv[arg_index], "noaa")) return false;
 			aa = strncasecmp(argv[arg_index++], "no", 2) != 0;
 			if (argc > arg_index) return false;
 		}
@@ -2171,7 +2171,7 @@ DEF_CONSOLE_CMD(ConListDirs)
 
 	std::set<std::string> seen_dirs;
 	for (const SubdirNameMap &sdn : subdir_name_map) {
-		if (strcasecmp(argv[1], sdn.name) != 0)  continue;
+		if (!StrEqualsIgnoreCase(argv[1], sdn.name))  continue;
 		bool found = false;
 		for (Searchpath sp : _valid_searchpaths) {
 			/* Get the directory */
@@ -2256,7 +2256,7 @@ DEF_CONSOLE_CMD(ConNewGRFProfile)
 	/* "unselect" sub-command */
 	if (strncasecmp(argv[1], "uns", 3) == 0 && argc >= 3) {
 		for (size_t argnum = 2; argnum < argc; ++argnum) {
-			if (strcasecmp(argv[argnum], "all") == 0) {
+			if (StrEqualsIgnoreCase(argv[argnum], "all")) {
 				_newgrf_profilers.clear();
 				break;
 			}
@@ -2501,17 +2501,17 @@ DEF_CONSOLE_CMD(ConDumpInfo)
 		return true;
 	}
 
-	if (strcasecmp(argv[1], "roadtypes") == 0) {
+	if (StrEqualsIgnoreCase(argv[1], "roadtypes")) {
 		ConDumpRoadTypes();
 		return true;
 	}
 
-	if (strcasecmp(argv[1], "railtypes") == 0) {
+	if (StrEqualsIgnoreCase(argv[1], "railtypes")) {
 		ConDumpRailTypes();
 		return true;
 	}
 
-	if (strcasecmp(argv[1], "cargotypes") == 0) {
+	if (StrEqualsIgnoreCase(argv[1], "cargotypes")) {
 		ConDumpCargoTypes();
 		return true;
 	}
diff --git a/src/driver.cpp b/src/driver.cpp
index 29f1946fad..b6bf486427 100644
--- a/src/driver.cpp
+++ b/src/driver.cpp
@@ -160,7 +160,7 @@ bool DriverFactoryBase::SelectDriverImpl(const std::string &name, Driver::Type t
 			if (d->type != type) continue;
 
 			/* Check driver name */
-			if (strcasecmp(dname.c_str(), d->name) != 0) continue;
+			if (!StrEqualsIgnoreCase(dname, d->name)) continue;
 
 			/* Found our driver, let's try it */
 			Driver *newd = d->CreateInstance();
diff --git a/src/fileio.cpp b/src/fileio.cpp
index 9a41a281e6..73b13e3117 100644
--- a/src/fileio.cpp
+++ b/src/fileio.cpp
@@ -1142,7 +1142,7 @@ static bool MatchesExtension(const char *extension, const char *filename)
 	if (extension == nullptr) return true;
 
 	const char *ext = strrchr(filename, extension[0]);
-	return ext != nullptr && strcasecmp(ext, extension) == 0;
+	return ext != nullptr && StrEqualsIgnoreCase(ext, extension);
 }
 
 /**
diff --git a/src/fios.cpp b/src/fios.cpp
index 793a4fd433..23fa6af2f7 100644
--- a/src/fios.cpp
+++ b/src/fios.cpp
@@ -216,7 +216,7 @@ static std::string FiosMakeFilename(const std::string *path, const char *name, c
 
 	/* Don't append the extension if it is already there */
 	const char *period = strrchr(name, '.');
-	if (period != nullptr && strcasecmp(period, ext) == 0) ext = "";
+	if (period != nullptr && StrEqualsIgnoreCase(period, ext)) ext = "";
 
 	return buf + PATHSEP + name + ext;
 }
@@ -473,14 +473,14 @@ FiosType FiosGetSavegameListCallback(SaveLoadOperation fop, const std::string &f
 	/* Don't crash if we supply no extension */
 	if (ext == nullptr) return FIOS_TYPE_INVALID;
 
-	if (strcasecmp(ext, ".sav") == 0) {
+	if (StrEqualsIgnoreCase(ext, ".sav")) {
 		GetFileTitle(file, title, last, SAVE_DIR);
 		return FIOS_TYPE_FILE;
 	}
 
 	if (fop == SLO_LOAD) {
-		if (strcasecmp(ext, ".ss1") == 0 || strcasecmp(ext, ".sv1") == 0 ||
-				strcasecmp(ext, ".sv2") == 0) {
+		if (StrEqualsIgnoreCase(ext, ".ss1") || StrEqualsIgnoreCase(ext, ".sv1") ||
+				StrEqualsIgnoreCase(ext, ".sv2")) {
 			if (title != nullptr) GetOldSaveGameName(file, title, last);
 			return FIOS_TYPE_OLDFILE;
 		}
@@ -523,13 +523,13 @@ static FiosType FiosGetScenarioListCallback(SaveLoadOperation fop, const std::st
 	 * .SCN OpenTTD style scenario file
 	 * .SV0 Transport Tycoon Deluxe (Patch) scenario
 	 * .SS0 Transport Tycoon Deluxe preset scenario */
-	if (strcasecmp(ext, ".scn") == 0) {
+	if (StrEqualsIgnoreCase(ext, ".scn")) {
 		GetFileTitle(file, title, last, SCENARIO_DIR);
 		return FIOS_TYPE_SCENARIO;
 	}
 
 	if (fop == SLO_LOAD) {
-		if (strcasecmp(ext, ".sv0") == 0 || strcasecmp(ext, ".ss0") == 0 ) {
+		if (StrEqualsIgnoreCase(ext, ".sv0") || StrEqualsIgnoreCase(ext, ".ss0")) {
 			GetOldSaveGameName(file, title, last);
 			return FIOS_TYPE_OLD_SCENARIO;
 		}
@@ -568,10 +568,10 @@ static FiosType FiosGetHeightmapListCallback(SaveLoadOperation fop, const std::s
 	FiosType type = FIOS_TYPE_INVALID;
 
 #ifdef WITH_PNG
-	if (strcasecmp(ext, ".png") == 0) type = FIOS_TYPE_PNG;
+	if (StrEqualsIgnoreCase(ext, ".png")) type = FIOS_TYPE_PNG;
 #endif /* WITH_PNG */
 
-	if (strcasecmp(ext, ".bmp") == 0) type = FIOS_TYPE_BMP;
+	if (StrEqualsIgnoreCase(ext, ".bmp")) type = FIOS_TYPE_BMP;
 
 	if (type == FIOS_TYPE_INVALID) return FIOS_TYPE_INVALID;
 
@@ -760,7 +760,7 @@ FiosNumberedSaveName::FiosNumberedSaveName(const std::string &prefix) : prefix(p
 
 	/* Callback for FiosFileScanner. */
 	static fios_getlist_callback_proc *proc = [](SaveLoadOperation fop, const std::string &file, const char *ext, char *title, const char *last) {
-		if (strcasecmp(ext, ".sav") == 0 && StrStartsWith(file, _prefix)) return FIOS_TYPE_FILE;
+		if (StrEqualsIgnoreCase(ext, ".sav") && StrStartsWith(file, _prefix)) return FIOS_TYPE_FILE;
 		return FIOS_TYPE_INVALID;
 	};
 
diff --git a/src/game/game_scanner.cpp b/src/game/game_scanner.cpp
index 1935b78137..367645083b 100644
--- a/src/game/game_scanner.cpp
+++ b/src/game/game_scanner.cpp
@@ -62,7 +62,7 @@ GameInfo *GameScannerInfo::FindInfo(const char *nameParam, int versionParam, boo
 	 *  version which allows loading the requested version */
 	for (const auto &item : this->info_list) {
 		GameInfo *i = static_cast<GameInfo *>(item.second);
-		if (strcasecmp(game_name, i->GetName()) == 0 && i->CanLoadFromVersion(versionParam) && (version == -1 || i->GetVersion() > version)) {
+		if (StrEqualsIgnoreCase(game_name, i->GetName()) && i->CanLoadFromVersion(versionParam) && (version == -1 || i->GetVersion() > version)) {
 			version = item.second->GetVersion();
 			info = i;
 		}
diff --git a/src/newgrf_config.cpp b/src/newgrf_config.cpp
index 6610183c2c..0a4860c667 100644
--- a/src/newgrf_config.cpp
+++ b/src/newgrf_config.cpp
@@ -630,7 +630,7 @@ bool GRFFileScanner::AddFile(const std::string &filename, size_t basepath_length
 				/* Because there can be multiple grfs with the same name, make sure we checked all grfs with the same name,
 				 *  before inserting the entry. So insert a new grf at the end of all grfs with the same name, instead of
 				 *  just after the first with the same name. Avoids doubles in the list. */
-				if (strcasecmp(c->GetName(), d->GetName()) <= 0) {
+				if (StrCompareIgnoreCase(c->GetName(), d->GetName()) <= 0) {
 					stop = true;
 				} else if (stop) {
 					break;
diff --git a/src/os/unix/font_unix.cpp b/src/os/unix/font_unix.cpp
index e2315e3fc1..5027929be0 100644
--- a/src/os/unix/font_unix.cpp
+++ b/src/os/unix/font_unix.cpp
@@ -70,12 +70,12 @@ FT_Error GetFontByFaceName(const char *font_name, FT_Face *face)
 					FcPatternGetString(fs->fonts[i], FC_STYLE, 0, &style) == FcResultMatch) {
 
 					/* The correct style? */
-					if (font_style != nullptr && strcasecmp(font_style, (char *)style) != 0) continue;
+					if (font_style != nullptr && !StrEqualsIgnoreCase(font_style, (char *)style)) continue;
 
 					/* Font config takes the best shot, which, if the family name is spelled
 					 * wrongly a 'random' font, so check whether the family name is the
 					 * same as the supplied name */
-					if (strcasecmp(font_family, (char *)family) == 0) {
+					if (StrEqualsIgnoreCase(font_family, (char *)family)) {
 						err = FT_New_Face(_library, (char *)file, 0, face);
 					}
 				}
diff --git a/src/script/script_scanner.cpp b/src/script/script_scanner.cpp
index 3b76b7b651..b395b0ed59 100644
--- a/src/script/script_scanner.cpp
+++ b/src/script/script_scanner.cpp
@@ -115,7 +115,7 @@ void ScriptScanner::RegisterScript(ScriptInfo *info)
 		/* This script was already registered */
 #ifdef _WIN32
 		/* Windows doesn't care about the case */
-		if (strcasecmp(this->info_list[script_name]->GetMainScript(), info->GetMainScript()) == 0) {
+		if (StrEqualsIgnoreCase(this->info_list[script_name]->GetMainScript(), info->GetMainScript()) == 0) {
 #else
 		if (strcmp(this->info_list[script_name]->GetMainScript(), info->GetMainScript()) == 0) {
 #endif
@@ -231,7 +231,7 @@ static bool IsSameScript(const ContentInfo *ci, bool md5sum, ScriptInfo *info, S
 
 			/* Check the extension. */
 			const char *ext = strrchr(tar.first.c_str(), '.');
-			if (ext == nullptr || strcasecmp(ext, ".nut") != 0) continue;
+			if (ext == nullptr || !StrEqualsIgnoreCase(ext, ".nut")) continue;
 
 			checksum.AddFile(tar.first, 0, tar_filename);
 		}
diff --git a/src/string.cpp b/src/string.cpp
index ff91f95ca3..0f853f9112 100644
--- a/src/string.cpp
+++ b/src/string.cpp
@@ -368,6 +368,59 @@ bool StrEndsWith(const std::string_view str, const std::string_view suffix)
 	return str.compare(str.size() - suffix_len, suffix_len, suffix, 0, suffix_len) == 0;
 }
 
+/** Case insensitive implementation of the standard character type traits. */
+struct CaseInsensitiveCharTraits : public std::char_traits<char> {
+	static bool eq(char c1, char c2) { return toupper(c1) == toupper(c2); }
+	static bool ne(char c1, char c2) { return toupper(c1) != toupper(c2); }
+	static bool lt(char c1, char c2) { return toupper(c1) <  toupper(c2); }
+
+	static int compare(const char *s1, const char *s2, size_t n)
+	{
+		while (n-- != 0) {
+			if (toupper(*s1) < toupper(*s2)) return -1;
+			if (toupper(*s1) > toupper(*s2)) return 1;
+			++s1; ++s2;
+		}
+		return 0;
+	}
+
+	static const char *find(const char *s, int n, char a)
+	{
+		while (n-- > 0 && toupper(*s) != toupper(a)) {
+			++s;
+		}
+		return s;
+	}
+};
+
+/** Case insensitive string view. */
+typedef std::basic_string_view<char, CaseInsensitiveCharTraits> CaseInsensitiveStringView;
+
+/**
+ * Compares two string( view)s, while ignoring the case of the characters.
+ * @param str1 The first string.
+ * @param str2 The second string.
+ * @return Less than zero if str1 < str2, zero if str1 == str2, greater than
+ *         zero if str1 > str2. All ignoring the case of the characters.
+ */
+int StrCompareIgnoreCase(const std::string_view str1, const std::string_view str2)
+{
+	CaseInsensitiveStringView ci_str1{ str1.data(), str1.size() };
+	CaseInsensitiveStringView ci_str2{ str2.data(), str2.size() };
+	return ci_str1.compare(ci_str2);
+}
+
+/**
+ * Compares two string( view)s for equality, while ignoring the case of the characters.
+ * @param str1 The first string.
+ * @param str2 The second string.
+ * @return True iff both strings are equal, barring the case of the characters.
+ */
+bool StrEqualsIgnoreCase(const std::string_view str1, const std::string_view str2)
+{
+	if (str1.size() != str2.size()) return false;
+	return StrCompareIgnoreCase(str1, str2) == 0;
+}
 
 /** Scans the string for colour codes and strips them */
 void str_strip_colours(char *str)
@@ -728,7 +781,7 @@ int strnatcmp(const char *s1, const char *s2, bool ignore_garbage_at_front)
 #endif
 
 	/* Do a normal comparison if ICU is missing or if we cannot create a collator. */
-	return strcasecmp(s1, s2);
+	return StrCompareIgnoreCase(s1, s2);
 }
 
 #ifdef WITH_UNISCRIBE
diff --git a/src/string_func.h b/src/string_func.h
index 816f85cf57..5293691807 100644
--- a/src/string_func.h
+++ b/src/string_func.h
@@ -54,6 +54,9 @@ void StrTrimInPlace(std::string &str);
 bool StrStartsWith(const std::string_view str, const std::string_view prefix);
 bool StrEndsWith(const std::string_view str, const std::string_view suffix);
 
+[[nodiscard]] int StrCompareIgnoreCase(const std::string_view str1, const std::string_view str2);
+[[nodiscard]] bool StrEqualsIgnoreCase(const std::string_view str1, const std::string_view str2);
+
 /**
  * Check if a string buffer is empty.
  *
diff --git a/src/tests/CMakeLists.txt b/src/tests/CMakeLists.txt
index b920fd6fdb..6f5134d46f 100644
--- a/src/tests/CMakeLists.txt
+++ b/src/tests/CMakeLists.txt
@@ -1,5 +1,6 @@
 add_test_files(
     landscape_partial_pixel_z.cpp
     math_func.cpp
+    string_func.cpp
     test_main.cpp
 )
diff --git a/src/tests/math_func.cpp b/src/tests/math_func.cpp
index 0e58b79e42..6cc43f0146 100644
--- a/src/tests/math_func.cpp
+++ b/src/tests/math_func.cpp
@@ -5,7 +5,7 @@
  * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
  */
 
-/** @file math_func_test.cpp Test functionality from core/math_func. */
+/** @file math_func.cpp Test functionality from core/math_func. */
 
 #include "../stdafx.h"
 
diff --git a/src/tests/string_func.cpp b/src/tests/string_func.cpp
new file mode 100644
index 0000000000..3797f894e7
--- /dev/null
+++ b/src/tests/string_func.cpp
@@ -0,0 +1,160 @@
+/*
+ * This file is part of OpenTTD.
+ * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
+ * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/** @file string_func.cpp Test functionality from string_func. */
+
+#include "../stdafx.h"
+
+#include "../3rdparty/catch2/catch.hpp"
+
+#include "../string_func.h"
+
+TEST_CASE("StrCompareIgnoreCase - std::string")
+{
+	/* Same string, with different cases. */
+	CHECK(StrCompareIgnoreCase(std::string{""}, std::string{""}) == 0);
+	CHECK(StrCompareIgnoreCase(std::string{"a"}, std::string{"a"}) == 0);
+	CHECK(StrCompareIgnoreCase(std::string{"a"}, std::string{"A"}) == 0);
+	CHECK(StrCompareIgnoreCase(std::string{"A"}, std::string{"a"}) == 0);
+	CHECK(StrCompareIgnoreCase(std::string{"A"}, std::string{"A"}) == 0);
+
+	/* Not the same string. */
+	CHECK(StrCompareIgnoreCase(std::string{""}, std::string{"b"}) < 0);
+	CHECK(StrCompareIgnoreCase(std::string{"a"}, std::string{""}) > 0);
+
+	CHECK(StrCompareIgnoreCase(std::string{"a"}, std::string{"b"}) < 0);
+	CHECK(StrCompareIgnoreCase(std::string{"b"}, std::string{"a"}) > 0);
+	CHECK(StrCompareIgnoreCase(std::string{"a"}, std::string{"B"}) < 0);
+	CHECK(StrCompareIgnoreCase(std::string{"b"}, std::string{"A"}) > 0);
+	CHECK(StrCompareIgnoreCase(std::string{"A"}, std::string{"b"}) < 0);
+	CHECK(StrCompareIgnoreCase(std::string{"B"}, std::string{"a"}) > 0);
+
+	CHECK(StrCompareIgnoreCase(std::string{"a"}, std::string{"aa"}) < 0);
+	CHECK(StrCompareIgnoreCase(std::string{"aa"}, std::string{"a"}) > 0);
+}
+
+TEST_CASE("StrCompareIgnoreCase - char pointer")
+{
+	/* Same string, with different cases. */
+	CHECK(StrCompareIgnoreCase("", "") == 0);
+	CHECK(StrCompareIgnoreCase("a", "a") == 0);
+	CHECK(StrCompareIgnoreCase("a", "A") == 0);
+	CHECK(StrCompareIgnoreCase("A", "a") == 0);
+	CHECK(StrCompareIgnoreCase("A", "A") == 0);
+
+	/* Not the same string. */
+	CHECK(StrCompareIgnoreCase("", "b") < 0);
+	CHECK(StrCompareIgnoreCase("a", "") > 0);
+
+	CHECK(StrCompareIgnoreCase("a", "b") < 0);
+	CHECK(StrCompareIgnoreCase("b", "a") > 0);
+	CHECK(StrCompareIgnoreCase("a", "B") < 0);
+	CHECK(StrCompareIgnoreCase("b", "A") > 0);
+	CHECK(StrCompareIgnoreCase("A", "b") < 0);
+	CHECK(StrCompareIgnoreCase("B", "a") > 0);
+
+	CHECK(StrCompareIgnoreCase("a", "aa") < 0);
+	CHECK(StrCompareIgnoreCase("aa", "a") > 0);
+}
+
+TEST_CASE("StrCompareIgnoreCase - std::string_view")
+{
+	/*
+	 * With std::string_view the only way to access the data is via .data(),
+	 * which does not guarantee the termination that would be required by
+	 * things such as stricmp/strcasecmp. So, just passing .data() into stricmp
+	 * or strcasecmp would fail if it does not account for the length of the
+	 * view. Thus, contrary to the string/char* tests, this uses the same base
+	 * string but gets different sections to trigger these corner cases.
+	 */
+	std::string_view base{"aaAbB"};
+
+	/* Same string, with different cases. */
+	CHECK(StrCompareIgnoreCase(base.substr(0, 0), base.substr(1, 0)) == 0); // Different positions
+	CHECK(StrCompareIgnoreCase(base.substr(0, 1), base.substr(1, 1)) == 0); // Different positions
+	CHECK(StrCompareIgnoreCase(base.substr(0, 1), base.substr(2, 1)) == 0);
+	CHECK(StrCompareIgnoreCase(base.substr(2, 1), base.substr(1, 1)) == 0);
+	CHECK(StrCompareIgnoreCase(base.substr(2, 1), base.substr(2, 1)) == 0);
+
+	/* Not the same string. */
+	CHECK(StrCompareIgnoreCase(base.substr(3, 0), base.substr(3, 1)) < 0); // Same position, different lengths
+	CHECK(StrCompareIgnoreCase(base.substr(0, 1), base.substr(0, 0)) > 0); // Same position, different lengths
+
+	CHECK(StrCompareIgnoreCase(base.substr(0, 1), base.substr(3, 1)) < 0);
+	CHECK(StrCompareIgnoreCase(base.substr(3, 1), base.substr(0, 1)) > 0);
+	CHECK(StrCompareIgnoreCase(base.substr(0, 1), base.substr(4, 1)) < 0);
+	CHECK(StrCompareIgnoreCase(base.substr(3, 1), base.substr(2, 1)) > 0);
+	CHECK(StrCompareIgnoreCase(base.substr(2, 1), base.substr(3, 1)) < 0);
+	CHECK(StrCompareIgnoreCase(base.substr(4, 1), base.substr(0, 1)) > 0);
+
+	CHECK(StrCompareIgnoreCase(base.substr(0, 1), base.substr(0, 2)) < 0); // Same position, different lengths
+	CHECK(StrCompareIgnoreCase(base.substr(0, 2), base.substr(0, 1)) > 0); // Same position, different lengths
+}
+
+TEST_CASE("StrEqualsIgnoreCase - std::string")
+{
+	/* Same string, with different cases. */
+	CHECK(StrEqualsIgnoreCase(std::string{""}, std::string{""}));
+	CHECK(StrEqualsIgnoreCase(std::string{"a"}, std::string{"a"}));
+	CHECK(StrEqualsIgnoreCase(std::string{"a"}, std::string{"A"}));
+	CHECK(StrEqualsIgnoreCase(std::string{"A"}, std::string{"a"}));
+	CHECK(StrEqualsIgnoreCase(std::string{"A"}, std::string{"A"}));
+
+	/* Not the same string. */
+	CHECK(!StrEqualsIgnoreCase(std::string{""}, std::string{"b"}));
+	CHECK(!StrEqualsIgnoreCase(std::string{"a"}, std::string{""}));
+	CHECK(!StrEqualsIgnoreCase(std::string{"a"}, std::string{"b"}));
+	CHECK(!StrEqualsIgnoreCase(std::string{"b"}, std::string{"a"}));
+	CHECK(!StrEqualsIgnoreCase(std::string{"a"}, std::string{"aa"}));
+	CHECK(!StrEqualsIgnoreCase(std::string{"aa"}, std::string{"a"}));
+}
+
+TEST_CASE("StrEqualsIgnoreCase - char pointer")
+{
+	/* Same string, with different cases. */
+	CHECK(StrEqualsIgnoreCase("", ""));
+	CHECK(StrEqualsIgnoreCase("a", "a"));
+	CHECK(StrEqualsIgnoreCase("a", "A"));
+	CHECK(StrEqualsIgnoreCase("A", "a"));
+	CHECK(StrEqualsIgnoreCase("A", "A"));
+
+	/* Not the same string. */
+	CHECK(!StrEqualsIgnoreCase("", "b"));
+	CHECK(!StrEqualsIgnoreCase("a", ""));
+	CHECK(!StrEqualsIgnoreCase("a", "b"));
+	CHECK(!StrEqualsIgnoreCase("b", "a"));
+	CHECK(!StrEqualsIgnoreCase("a", "aa"));
+	CHECK(!StrEqualsIgnoreCase("aa", "a"));
+}
+
+TEST_CASE("StrEqualsIgnoreCase - std::string_view")
+{
+	/*
+	 * With std::string_view the only way to access the data is via .data(),
+	 * which does not guarantee the termination that would be required by
+	 * things such as stricmp/strcasecmp. So, just passing .data() into stricmp
+	 * or strcasecmp would fail if it does not account for the length of the
+	 * view. Thus, contrary to the string/char* tests, this uses the same base
+	 * string but gets different sections to trigger these corner cases.
+	 */
+	std::string_view base{"aaAb"};
+
+	/* Same string, with different cases. */
+	CHECK(StrEqualsIgnoreCase(base.substr(0, 0), base.substr(1, 0))); // Different positions
+	CHECK(StrEqualsIgnoreCase(base.substr(0, 1), base.substr(1, 1))); // Different positions
+	CHECK(StrEqualsIgnoreCase(base.substr(0, 1), base.substr(2, 1)));
+	CHECK(StrEqualsIgnoreCase(base.substr(2, 1), base.substr(1, 1)));
+	CHECK(StrEqualsIgnoreCase(base.substr(2, 1), base.substr(2, 1)));
+
+	/* Not the same string. */
+	CHECK(!StrEqualsIgnoreCase(base.substr(3, 0), base.substr(3, 1))); // Same position, different lengths
+	CHECK(!StrEqualsIgnoreCase(base.substr(0, 1), base.substr(0, 0)));
+	CHECK(!StrEqualsIgnoreCase(base.substr(0, 1), base.substr(3, 1)));
+	CHECK(!StrEqualsIgnoreCase(base.substr(3, 1), base.substr(0, 1)));
+	CHECK(!StrEqualsIgnoreCase(base.substr(0, 1), base.substr(0, 2))); // Same position, different lengths
+	CHECK(!StrEqualsIgnoreCase(base.substr(0, 2), base.substr(0, 1))); // Same position, different lengths
+}