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

[Paul Kirth via cfe-commits]

================
@@ -0,0 +1,177 @@
+//===----------------------------------------------------------------------===//
+//
+// 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 "Markdown.h"
+#include "llvm/Support/Casting.h"
+
+namespace clang::doc::markdown {
+
+//===----------------------------------------------------------------------===//
+// Inline node print/dump
+//===----------------------------------------------------------------------===//
+
+void InlineNode::print(llvm::raw_ostream &OS) const {
+  switch (Kind) {
+  case NodeKind::NK_Text:
+    llvm::cast<TextNode>(this)->print(OS);
+    break;
+  case NodeKind::NK_InlineCode:
+    llvm::cast<InlineCodeNode>(this)->print(OS);
+    break;
+  case NodeKind::NK_Emphasis:
+    llvm::cast<EmphasisNode>(this)->print(OS);
+    break;
+  case NodeKind::NK_Strong:
+    llvm::cast<StrongNode>(this)->print(OS);
+    break;
+  default:
+    OS << "UnknownInlineNode\n";
+    break;
+  }
+}
+
+LLVM_DUMP_METHOD void InlineNode::dump() const { print(llvm::errs()); }
+
+void TextNode::print(llvm::raw_ostream &OS) const {
+  OS << "TextNode: " << getText() << "\n";
+}
+
+LLVM_DUMP_METHOD void TextNode::dump() const { print(llvm::errs()); }
+
+void InlineCodeNode::print(llvm::raw_ostream &OS) const {
+  OS << "InlineCodeNode: " << getCode() << "\n";
+}
+
+LLVM_DUMP_METHOD void InlineCodeNode::dump() const { print(llvm::errs()); }
+
+void EmphasisNode::print(llvm::raw_ostream &OS) const {
+  OS << "EmphasisNode\n";
+  for (const auto &Child : Children)
+    Child.print(OS);
+}
+
+LLVM_DUMP_METHOD void EmphasisNode::dump() const { print(llvm::errs()); }
+
+void StrongNode::print(llvm::raw_ostream &OS) const {
+  OS << "StrongNode\n";
+  for (const auto &Child : Children)
+    Child.print(OS);
+}
+
+LLVM_DUMP_METHOD void StrongNode::dump() const { print(llvm::errs()); }
+
+//===----------------------------------------------------------------------===//
+// Block node print/dump
+//===----------------------------------------------------------------------===//
+
+void BlockNode::print(llvm::raw_ostream &OS) const {
+  switch (Kind) {
+  case NodeKind::NK_Paragraph:
+    llvm::cast<ParagraphNode>(this)->print(OS);
+    break;
+  case NodeKind::NK_Heading:
+    llvm::cast<HeadingNode>(this)->print(OS);
+    break;
+  case NodeKind::NK_FencedCode:
+    llvm::cast<FencedCodeNode>(this)->print(OS);
+    break;
+  case NodeKind::NK_UnorderedList:
+    llvm::cast<UnorderedListNode>(this)->print(OS);
+    break;
+  case NodeKind::NK_OrderedList:
+    llvm::cast<OrderedListNode>(this)->print(OS);
+    break;
+  case NodeKind::NK_ListItem:
+    llvm::cast<ListItemNode>(this)->print(OS);
+    break;
+  case NodeKind::NK_BlockQuote:
+    llvm::cast<BlockQuoteNode>(this)->print(OS);
+    break;
+  case NodeKind::NK_ThematicBreak:
+    llvm::cast<ThematicBreakNode>(this)->print(OS);
+    break;
+  case NodeKind::NK_Document:
+    llvm::cast<DocumentNode>(this)->print(OS);
+    break;
+  default:
+    OS << "UnknownBlockNode\n";
+    break;
----------------
ilovepi wrote:

please omit the default case in switches like this. We use the `enum class` because it will break -Werror` builds if the enum isn't covered fully. Many other places in llvm use `llvm_unreachable` after the switch to be doubly sure (e..g. because they return instead of `break;`). I'd encourage you to take a look at other implementations throughout the broader codebase.

 That said, its a bit questionable to have this kind of casting in the base classes.

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