[all-commits] [llvm/llvm-project] 8adc4d: [clangd] Add textDocument/ast extension method to ...

[Sam McCall via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: 8adc4d1ec76471bc283d888f3077f7d8f591d6ad
      https://github.com/llvm/llvm-project/commit/8adc4d1ec76471bc283d888f3077f7d8f591d6ad
  Author: Sam McCall <sam.mccall at gmail.com>
  Date:   2020-11-20 (Fri, 20 Nov 2020)

  Changed paths:
    M clang-tools-extra/clangd/CMakeLists.txt
    M clang-tools-extra/clangd/ClangdLSPServer.cpp
    M clang-tools-extra/clangd/ClangdLSPServer.h
    M clang-tools-extra/clangd/ClangdServer.cpp
    M clang-tools-extra/clangd/ClangdServer.h
    A clang-tools-extra/clangd/DumpAST.cpp
    A clang-tools-extra/clangd/DumpAST.h
    M clang-tools-extra/clangd/Protocol.cpp
    M clang-tools-extra/clangd/Protocol.h
    A clang-tools-extra/clangd/test/ast.test
    M clang-tools-extra/clangd/test/initialize-params.test
    M clang-tools-extra/clangd/unittests/CMakeLists.txt
    A clang-tools-extra/clangd/unittests/DumpASTTests.cpp

  Log Message:
  -----------
  [clangd] Add textDocument/ast extension method to dump the AST

This is a mass-market version of the "dump AST" tweak we have behind
-hidden-features.
I think in this friendlier form it'll be useful for people outside clang
developers, which would justify making it a real feature.
It could be useful as a step towards lightweight clang-AST tooling in clangd
itself (like matcher-based search).

Advantages over the tweak:
 - simplified information makes it more accessible, likely somewhat useful
   without learning too much clang internals
 - can be shown in a tree view
 - structured information gives some options for presentation (e.g.
   icon + two text colors + tooltip in vscode)
 - clickable nodes jump to the corresponding code
Disadvantages:
 - a bunch of code to handle different node types
 - likely missing some important info vs dump-ast due to brevity/oversight
 - may end up chasing/maintaining support for the long tail of nodes

Demo with VSCode support: https://imgur.com/a/6gKfyIV

Differential Revision: https://reviews.llvm.org/D89571