[libcxx] [libcxxabi] [libunwind] [llvm] [libc++][WIP] Move the libc++ test format to Lit (PR #90803)

[Mark de Wever via cfe-commits]

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@@ -0,0 +1,355 @@
+# ===----------------------------------------------------------------------===##
+#
+# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+# See https://llvm.org/LICENSE.txt for license information.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+#
+# ===----------------------------------------------------------------------===##
+
+import lit
+import os
+import re
+from .base import FileBasedTest
+
+
+def _getSubstitution(substitution, config):
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mordante wrote:

There is a duplicate of this function in `utils/libcxx/test/config.py`. Cleaning this up is on my todo list, however would it make sense to do that in this patch?

https://github.com/llvm/llvm-project/pull/90803