[clang-tools-extra] [llvm] [llvm] add support for mustache templating language (PR #105893)

[Aaron Ballman via llvm-commits]

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@@ -0,0 +1,785 @@
+//===-- Mustache.cpp ------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Support/Mustache.h"
+#include "llvm/Support/Error.h"
+#include "llvm/Support/raw_ostream.h"
+#include <sstream>
+
+using namespace llvm;
+using namespace llvm::json;
+using namespace llvm::mustache;
+
+namespace {
+
+static bool isFalsey(const Value &V) {
+  return V.getAsNull() || (V.getAsBoolean() && !V.getAsBoolean().value()) ||
+         (V.getAsArray() && V.getAsArray()->empty()) ||
+         (V.getAsObject() && V.getAsObject()->empty());
+}
+
+static Accessor splitMustacheString(StringRef Str) {
+  // We split the mustache string into an accessor.
+  // For example:
+  //    "a.b.c" would be split into {"a", "b", "c"}
+  // We make an exception for a single dot which
+  // refers to the current context.
+  Accessor Tokens;
+  if (Str == ".") {
+    Tokens.emplace_back(Str);
+    return Tokens;
+  }
+  while (!Str.empty()) {
+    StringRef Part;
+    std::tie(Part, Str) = Str.split(".");
+    Tokens.emplace_back(Part.trim());
+  }
+  return Tokens;
+}
+
+} // namespace
+
+namespace llvm {
+namespace mustache {
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AaronBallman wrote:

`namespace llvm::mustache` instead?

https://github.com/llvm/llvm-project/pull/105893