[clang-tools-extra] [clang-doc] Add Markdown AST node type definitions (PR #205609)

[Neil Nair via cfe-commits]

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@@ -0,0 +1,269 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_DOC_SUPPORT_MARKDOWN_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_DOC_SUPPORT_MARKDOWN_H
+
+#include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/simple_ilist.h"
+#include "llvm/Support/Allocator.h"
+#include "llvm/Support/Casting.h"
+#include "llvm/Support/StringSaver.h"
+#include "llvm/Support/raw_ostream.h"
+#include <type_traits>
+
+namespace clang::doc::markdown {
+
+enum class NodeKind {
+  // Inline nodes
+  NK_Text,
+  NK_InlineCode,
+  NK_Emphasis,
+  NK_Strong,
+  // Block nodes
+  NK_Paragraph,
+  NK_Heading,
+  NK_FencedCode,
+  NK_Table,
+  NK_UnorderedList,
+  NK_OrderedList,
+  NK_ListItem,
+  NK_BlockQuote,
+  NK_ThematicBreak,
+  NK_Document,
+};
+
+// Forward declarations
+struct InlineNode;
+struct BlockNode;
+
+//===----------------------------------------------------------------------===//
+// Inline nodes
+//===----------------------------------------------------------------------===//
+
+struct InlineNode
+    : llvm::ilist_node<InlineNode, llvm::ilist_sentinel_tracking<true>> {
+  NodeKind Kind;
+  explicit InlineNode(NodeKind K) : Kind(K) {}
+  void dump(llvm::raw_ostream &OS = llvm::errs()) const;
+};
+
+struct TextNode : InlineNode {
+private:
+  llvm::StringRef Text;
+
+public:
+  explicit TextNode(llvm::StringRef T)
+      : InlineNode(NodeKind::NK_Text), Text(T) {}
+  llvm::StringRef getText() const { return Text; }
+  void dump(llvm::raw_ostream &OS = llvm::errs()) const {
+    OS << "TextNode: " << Text << "\n";
+  }
+  static bool classof(const InlineNode *N) {
+    return N->Kind == NodeKind::NK_Text;
+  }
+};
+static_assert(std::is_trivially_destructible_v<TextNode>);
+
+struct InlineCodeNode : InlineNode {
+private:
+  llvm::StringRef Code;
+
+public:
+  explicit InlineCodeNode(llvm::StringRef C)
+      : InlineNode(NodeKind::NK_InlineCode), Code(C) {}
+  llvm::StringRef getCode() const { return Code; }
+  void dump(llvm::raw_ostream &OS = llvm::errs()) const {
+    OS << "InlineCodeNode: " << Code << "\n";
+  }
+  static bool classof(const InlineNode *N) {
+    return N->Kind == NodeKind::NK_InlineCode;
+  }
+};
+static_assert(std::is_trivially_destructible_v<InlineCodeNode>);
+
+struct EmphasisNode : InlineNode {
+  llvm::simple_ilist<InlineNode, llvm::ilist_sentinel_tracking<true>> Children;
+  EmphasisNode() : InlineNode(NodeKind::NK_Emphasis) {}
+  void dump(llvm::raw_ostream &OS = llvm::errs()) const {
+    OS << "EmphasisNode\n";
+  }
+  static bool classof(const InlineNode *N) {
+    return N->Kind == NodeKind::NK_Emphasis;
+  }
+};
+
+struct StrongNode : InlineNode {
+  llvm::simple_ilist<InlineNode, llvm::ilist_sentinel_tracking<true>> Children;
+  StrongNode() : InlineNode(NodeKind::NK_Strong) {}
+  void dump(llvm::raw_ostream &OS = llvm::errs()) const {
+    OS << "StrongNode\n";
+  }
+  static bool classof(const InlineNode *N) {
+    return N->Kind == NodeKind::NK_Strong;
+  }
+};
+
+//===----------------------------------------------------------------------===//
+// Block nodes
+//===----------------------------------------------------------------------===//
+
+struct BlockNode
+    : llvm::ilist_node<BlockNode, llvm::ilist_sentinel_tracking<true>> {
+  NodeKind Kind;
+  explicit BlockNode(NodeKind K) : Kind(K) {}
+  void dump(llvm::raw_ostream &OS = llvm::errs()) const;
+};
+
+using InlineList =
+    llvm::simple_ilist<InlineNode, llvm::ilist_sentinel_tracking<true>>;
+using BlockList =
+    llvm::simple_ilist<BlockNode, llvm::ilist_sentinel_tracking<true>>;
+
+struct ParagraphNode : BlockNode {
+  InlineList Children;
+  ParagraphNode() : BlockNode(NodeKind::NK_Paragraph) {}
+  void dump(llvm::raw_ostream &OS = llvm::errs()) const {
+    OS << "ParagraphNode\n";
+  }
----------------
Neil-N4 wrote:

Moved implementations to Markdown.cpp using LLVM_DUMP_METHOD and a separate print() that recurses into children

https://github.com/llvm/llvm-project/pull/205609