[clang-tools-extra] [llvm] [llvm] add tool to verify mustache library (PR #111487)

[Nikita Popov via llvm-commits]

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@@ -0,0 +1,104 @@
+//===- llvm-mustachespec.cpp - The LLVM Modular Optimizer
+//===----------------------------------------------------------------------===//
+//
+// 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 here
+// https://github.com/mustache/
+// It is used to verify that the current implementation conforms to the spec
+// simply download the spec and pass the test files to the driver
+//
+// Currently Triple Mustache is not supported we expect the following spec
+// test to fail:
+//    Triple Mustache
+//    Triple Mustache Integer Interpolation
+//    Triple Mustache Decimal Interpolation
+//    Triple Mustache Null Interpolation
+//    Triple Mustache Context Miss Interpolation
+//    Dotted Names - Triple Mustache Interpolation
+//    Implicit Iterators - Triple Mustache
+//    Triple Mustache - Surrounding Whitespace
+//    Triple Mustache - Standalone
+//    Triple Mustache With Padding
+//    Standalone Indentation
+//    Implicit Iterator - Triple mustache
+//
+// Usage:
+//  mustache path/to/test/file/test.json path/to/test/file/test2.json ...
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/Mustache.h"
+#include <string>
+
+using namespace llvm;
+using namespace llvm::json;
+using namespace llvm::mustache;
+
+cl::list<std::string> InputFiles(cl::Positional, cl::desc("<input files>"),
+                                 cl::OneOrMore);
+
+void runThroughTest(StringRef InputFile) {
+  llvm::outs() << "Running Tests: " << InputFile << "\n";
----------------
nikic wrote:

```suggestion
  outs() << "Running Tests: " << InputFile << "\n";
```
You're using `using namespace llvm`, don't need all these `llvm::` prefixes.

https://github.com/llvm/llvm-project/pull/111487