[llvm] [llvm] Add a tool to check mustache compliance against the public spec (PR #142813)

[Nikita Popov via llvm-commits]

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@@ -0,0 +1,157 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// Simple drivers to test the mustache spec found at
+// https://github.com/mustache/
----------------
nikic wrote:

```suggestion
// https://github.com/mustache/spec
```

https://github.com/llvm/llvm-project/pull/142813