[clang-tools-extra] [clang-doc] Add HTMLMustacheGenerator.cpp (PR #138060)

[Paul Kirth via cfe-commits]

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@@ -0,0 +1,85 @@
+//===-- HTMLMustacheGenerator.cpp - HTML Mustache Generator -----*- C++ -*-===//
+//
+// 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 "Generators.h"
+#include "Representation.h"
+#include "support/File.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/Mustache.h"
+
+using namespace llvm;
+using namespace llvm::json;
+using namespace llvm::mustache;
+
+namespace clang {
+namespace doc {
+
+class MustacheHTMLGenerator : public Generator {
+public:
+  static const char *Format;
+  Error generateDocs(StringRef RootDir,
+                     StringMap<std::unique_ptr<doc::Info>> Infos,
+                     const ClangDocContext &CDCtx) override;
+  Error createResources(ClangDocContext &CDCtx) override;
+  Error generateDocForInfo(Info *I, raw_ostream &OS,
+                           const ClangDocContext &CDCtx) override;
+};
+
+class MustacheTemplateFile : public Template {
+public:
+  static ErrorOr<std::unique_ptr<MustacheTemplateFile>>
+  createMustacheFile(StringRef FileName) {
+    ErrorOr<std::unique_ptr<MemoryBuffer>> BufferOrError =
+        MemoryBuffer::getFile(FileName);
+    if (auto EC = BufferOrError.getError())
+      return EC;
+
+    std::unique_ptr<MemoryBuffer> Buffer = std::move(BufferOrError.get());
+    StringRef FileContent = Buffer->getBuffer();
+    return std::make_unique<MustacheTemplateFile>(FileContent);
+  }
+
+  Error registerPartialFile(StringRef Name, StringRef FileName) {
+    ErrorOr<std::unique_ptr<MemoryBuffer>> BufferOrError =
+        MemoryBuffer::getFile(FileName);
+    if (auto EC = BufferOrError.getError())
+      return createFileError("cannot open file", EC);
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ilovepi wrote:

`registerPartialFile` only returns an `Error`, while `createMustacheFile` returns an `ErrorOr<T>`.  Maybe `registerPartialFile` should use `errorCodeToError` to convert instead of `createFileError`?

https://github.com/llvm/llvm-project/pull/138060