Feature/memory arena (#631)

* First pass at MemoryArena.

* First pass at RandomGenerator.

* Extract TestContext into external source file.

* Fix warning on printf.

* Use enum classes for Test enums.
OutputMode -> TestOutputMode.

* First pass at FreeList unit test.

* Auto registering tests.
Improvements to RandomGenerator.

* Remove the need for unitTest headers - cos can use registering.

* Added unitTest for MemoryArena.

* Do unit tests.

* Fix typo.

1 files changed, 48 insertions, 0 deletions

diff --git a/source/core/slang-string-util.cpp b/source/core/slang-string-util.cpp
index c60ad9683..29f8dc0ca 100644
--- a/source/core/slang-string-util.cpp
+++ b/source/core/slang-string-util.cpp
@@ -26,4 +26,52 @@ namespace Slang {
     }
 }
 
+
+/* static */void StringUtil::append(const char* format, va_list args, StringBuilder& buf)
+{
+    int numChars = 0;
+
+#if SLANG_WINDOWS_FAMILY
+    numChars = _vscprintf(format, args);
+#else
+    {
+        va_list argsCopy;
+        va_copy(argsCopy, args);
+        numChars = vsnprintf(nullptr, 0, format, argsCopy);
+        va_end(argsCopy);
+    }
+#endif
+
+    List<char> chars;
+    chars.SetSize(numChars + 1);
+
+#if SLANG_WINDOWS_FAMILY
+    vsnprintf_s(chars.Buffer(), numChars + 1, _TRUNCATE, format, args);
+#else
+    vsnprintf(chars.Buffer(), numChars + 1, format, args);
+#endif
+
+    buf.Append(chars.Buffer(), numChars);
+}
+
+/* static */void StringUtil::appendFormat(StringBuilder& buf, const char* format, ...)
+{
+    va_list args;
+    va_start(args, format);
+    append(format, args, buf);
+    va_end(args);
+}
+
+/* static */String StringUtil::makeStringWithFormat(const char* format, ...)
+{
+    StringBuilder builder;
+
+    va_list args;
+    va_start(args, format);
+    append(format, args, builder);
+    va_end(args);
+
+    return builder;
+}
+
 } // namespace Slang