Implement ICU support for uppercasing, with tests.

src/openrct2/core/String.hpp

@@ -111,4 +111,9 @@ namespace String
      * Converts a multi-byte string from one code page to another.
      */
     std::string Convert(const std::string_view& src, sint32 srcCodePage, sint32 dstCodePage);
-} // namespace String
+
+    /**
+     * Returns an uppercased version of a UTF-8 string.
+     */
+    std::string ToUpper(const utf8 * src);
+}

src/openrct2/localisation/Localisation.cpp

@@ -31,6 +31,7 @@
 #include "../common.h"
 #include "../config/Config.h"
 #include "../core/Math.hpp"
+#include "../core/String.hpp"
 #include "../core/Util.hpp"
 #include "Date.h"
 #include "../Game.h"
@@ -1215,12 +1216,16 @@ void format_string_to_upper(utf8 *dest, size_t size, rct_string_id format, void
 
     format_string(dest, size, format, args);
 
-    // Convert to upper case
-    utf8 *ch = dest;
-    while (*ch != '\0') {
-        *ch = toupper(*ch);
-        ch++;
+    std::string upperString = String::ToUpper(dest);
+
+    if (upperString.size() + 1 >= size) {
+        upperString.resize(size - 1);
+        dest[size - 1] = '\0';
+        log_warning("Truncating formatted string \"%s\" to %d bytes.", dest, size);
     }
+
+    upperString.copy(dest, upperString.size());
+    dest[upperString.size()] = '\0';
 }
 
 money32 string_to_money(char * string_to_monetise)

test/tests/StringTest.cpp

@@ -114,3 +114,18 @@ TEST_F(StringTest, Convert_Empty)
 }
 
 #endif
+
+///////////////////////////////////////////////////////////////////////////////
+// Tests for String::ToUpper
+///////////////////////////////////////////////////////////////////////////////
+
+TEST_F(StringTest, ToUpper_Basic)
+{
+    auto actual = String::ToUpper("test TEST tEsT 1234");
+    ASSERT_STREQ(actual.c_str(), "TEST TEST TEST 1234");
+}
+TEST_F(StringTest, ToUpper_Unicode)
+{
+    auto actual = String::ToUpper("éœǘξдȿ𞥃ꜳᲁ ÉŒǗΞДⱾ𞤡ꜲД 語");
+    ASSERT_STREQ(actual.c_str(), "ÉŒǗΞДⱾ𞤡ꜲД ÉŒǗΞДⱾ𞤡ꜲД 語");
+}