diff --git a/Sources/Plasma/CoreLib/plFormat.cpp b/Sources/Plasma/CoreLib/plFormat.cpp
index 4126640f..abe8c465 100644
--- a/Sources/Plasma/CoreLib/plFormat.cpp
+++ b/Sources/Plasma/CoreLib/plFormat.cpp
@@ -294,9 +294,7 @@ static void _formatChar(const plFormat_Private::FormatSpec &format,
 
     // Yanked from plString
     if (ch > 0x10FFFF) {
-        hsAssert(0, "Unicode character out of range");
-
-        // Character out of range; Use U+FFFD instead for release builds
+        // Character out of range; Use U+FFFD instead
         format_size = 3;
         utf8[0] = 0xE0 | ((BADCHAR_REPLACEMENT >> 12) & 0x0F);
         utf8[1] = 0x80 | ((BADCHAR_REPLACEMENT >>  6) & 0x3F);
diff --git a/Sources/Tests/CoreTests/CMakeLists.txt b/Sources/Tests/CoreTests/CMakeLists.txt
index c10e7796..91b300a0 100644
--- a/Sources/Tests/CoreTests/CMakeLists.txt
+++ b/Sources/Tests/CoreTests/CMakeLists.txt
@@ -4,6 +4,7 @@ include_directories(../../Plasma/CoreLib)
 
 SET(CoreLibTest_SOURCES
     test_plString.cpp
+    test_plFormat.cpp
     test_plCmdParser.cpp
     )
 
diff --git a/Sources/Tests/CoreTests/test_plFormat.cpp b/Sources/Tests/CoreTests/test_plFormat.cpp
new file mode 100644
index 00000000..39b3de38
--- /dev/null
+++ b/Sources/Tests/CoreTests/test_plFormat.cpp
@@ -0,0 +1,85 @@
+#include "plFormat.h"
+#include "plFileSystem.h"
+
+#include <gtest/gtest.h>
+#include <string>
+
+TEST(plFormat, Escapes)
+{
+    EXPECT_EQ(plString("{x"), plFormat("{{{}", "x"));
+    EXPECT_EQ(plString("x{"), plFormat("{}{{", "x"));
+    EXPECT_EQ(plString("{{{{"), plFormat("{{{}{{{{", "{"));
+    EXPECT_EQ(plString("{xxx{{yyy{"), plFormat("{{{}{{{{{}{{", "xxx", "yyy"));
+}
+
+TEST(plFormat, Errors)
+{
+    EXPECT_DEATH(plFormat("{}", 1, 2),
+        "Message: Too many actual parameters for format string");
+    EXPECT_DEATH(plFormat("{} {}", 1),
+        "Message: Not enough actual parameters for format string");
+    EXPECT_DEATH(plFormat("{", 1),
+        "Message: Unterminated format specifier");
+    EXPECT_DEATH(plFormat("{.", 1),
+        "Message: Unterminated format specifier");
+    EXPECT_DEATH(plFormat("{_", 1),
+        "Message: Unterminated format specifier");
+    EXPECT_DEATH(plFormat(nullptr, 1),
+        "Message: Passed a null format string");
+}
+
+TEST(plFormat, Strings)
+{
+    EXPECT_EQ(plString("TEST"), plFormat("{}", "TEST"));
+    EXPECT_EQ(plString("xxTESTxx"), plFormat("xx{}xx", "TEST"));
+    EXPECT_EQ(plString("xxTESTxx"), plFormat("xx{2}xx", "TEST"));
+    EXPECT_EQ(plString("xxTESTxx"), plFormat("xx{>2}xx", "TEST"));
+    EXPECT_EQ(plString("xxTESTxx"), plFormat("xx{<2}xx", "TEST"));
+    EXPECT_EQ(plString("xxTESTxx"), plFormat("xx{_-2}xx", "TEST"));
+    EXPECT_EQ(plString("xxTEST  xx"), plFormat("xx{6}xx", "TEST"));
+    EXPECT_EQ(plString("xxTEST  xx"), plFormat("xx{<6}xx", "TEST"));
+    EXPECT_EQ(plString("xx  TESTxx"), plFormat("xx{>6}xx", "TEST"));
+    EXPECT_EQ(plString("xxTEST--xx"), plFormat("xx{_-6}xx", "TEST"));
+    EXPECT_EQ(plString("xxTEST--xx"), plFormat("xx{<_-6}xx", "TEST"));
+    EXPECT_EQ(plString("xx--TESTxx"), plFormat("xx{>_-6}xx", "TEST"));
+    EXPECT_EQ(plString("xxONE  TWO    THREExx"), plFormat("xx{5}{<5}{>7}xx", "ONE", "TWO", "THREE"));
+
+    // Ensure braces are parsed properly within padding chars
+    EXPECT_EQ(plString("xxTEST}}xx"), plFormat("xx{_}6}xx", "TEST"));
+    EXPECT_EQ(plString("xxTEST}}xx"), plFormat("xx{6_}}xx", "TEST"));
+    EXPECT_EQ(plString("xxTEST{{xx"), plFormat("xx{_{6}xx", "TEST"));
+    EXPECT_EQ(plString("xxTEST{{xx"), plFormat("xx{6_{}xx", "TEST"));
+}
+
+TEST(plFormat, StringClasses)
+{
+    // These should be handled just like normal const char* string params
+    // (see above), so just need to test that the wrappers are working
+    EXPECT_EQ(plString("xxтəßtxx"), plFormat("xx{}xx", L"тəßt"));
+    EXPECT_EQ(plString("xxтəßtxx"), plFormat("xx{}xx", plString("тəßt")));
+    EXPECT_EQ(plString("xxTESTxx"), plFormat("xx{}xx", std::string("TEST")));
+    EXPECT_EQ(plString("xxтəßtxx"), plFormat("xx{}xx", std::wstring(L"тəßt")));
+    EXPECT_EQ(plString("xx/dev/nullxx"), plFormat("xx{}xx", plFileName("/dev/null")));
+    EXPECT_EQ(plString(R"(xxC:\Users\Nobodyxx)"),
+              plFormat("xx{}xx", plFileName(R"(C:\Users\Nobody)")));
+}
+
+TEST(plFormat, Char)
+{
+    EXPECT_EQ(plString("xxAxx"), plFormat("xx{}xx", 'A'));
+    EXPECT_EQ(plString("xxAxx"), plFormat("xx{c}xx", (signed char)'A'));
+    EXPECT_EQ(plString("xxAxx"), plFormat("xx{c}xx", (unsigned char)'A'));
+
+    // UTF-8 encoding of wide (16-bit) char
+    EXPECT_EQ(plString("xx\xef\xbf\xbexx"), plFormat("xx{}xx", L'\ufffe'));
+    EXPECT_EQ(plString("xx\xe7\xbf\xbexx"), plFormat("xx{c}xx", (short)0x7ffe));
+    EXPECT_EQ(plString("xx\xef\xbf\xbexx"), plFormat("xx{c}xx", (unsigned short)0xfffe));
+
+    // UTF-8 encoding of UCS4 (32-bit) char
+    EXPECT_EQ(plString("xx\xf4\x8f\xbf\xbfxx"), plFormat("xx{c}xx", (int)0x10ffff));
+    EXPECT_EQ(plString("xx\xf4\x8f\xbf\xbfxx"), plFormat("xx{c}xx", (unsigned int)0x10ffff));
+    EXPECT_EQ(plString("xx\xf4\x8f\xbf\xbfxx"), plFormat("xx{c}xx", (long)0x10ffff));
+    EXPECT_EQ(plString("xx\xf4\x8f\xbf\xbfxx"), plFormat("xx{c}xx", (unsigned long)0x10ffff));
+    EXPECT_EQ(plString("xx\xf4\x8f\xbf\xbfxx"), plFormat("xx{c}xx", (int64_t)0x10ffff));
+    EXPECT_EQ(plString("xx\xf4\x8f\xbf\xbfxx"), plFormat("xx{c}xx", (uint64_t)0x10ffff));
+}