[clang-doc] Switch to default to all-TUs executor

[juliehockett]

Summary

Since we generally want to document a whole project, not just one file.

@ioeric, is this an acceptable way to do this? I want to be able to use any executor, but I'd like the default to be all-TUs instead of standalone.

[leonardchan]

clang-tools-extra/clang-doc/tool/ClangDocMain.cpp

90–92

I think this might be more than 80 characters in a line? Run clang-format just to be sure.

202–203

Formatting nit: Should the arguments be aligned here?

211–213

Nit: Remove braces

[Eugene.Zelenko]

clang-tools-extra/clang-doc/tool/ClangDocMain.cpp

204

Please don't use auto when type is not spelled in same statement.

208

Please use range loop.

[ioeric]

clang-tools-extra/clang-doc/tool/ClangDocMain.cpp

202

This is exposing too much implementation details.I landed a patch to expose the ExecutorName option from the library (rL344335) so you could simply do ExecutorName.setInitialValue("all-TUs") before calling createExecutorFromCommandLineArgs().

[juliehockett]

clang-tools-extra/clang-doc/tool/ClangDocMain.cpp

202

Perfect. Thanks!

[ioeric]

clang-tools-extra/clang-doc/tool/ClangDocMain.cpp

89–93

This flag can also be removed. Users can still use --executor to override the default.

clang-tools-extra/clang-doc/tool/ClangDocMain.cpp

 #include "Representation.h"
 #include "clang/AST/AST.h"
 #include "clang/AST/Decl.h"
 #include "clang/ASTMatchers/ASTMatchFinder.h"
 #include "clang/ASTMatchers/ASTMatchersInternal.h"
 #include "clang/Driver/Options.h"
 #include "clang/Frontend/FrontendActions.h"
 #include "clang/Tooling/CommonOptionsParser.h"
-#include "clang/Tooling/Execution.h"
-#include "clang/Tooling/StandaloneExecution.h"
+#include "clang/Tooling/ToolExecutorPluginRegistry.h"
 #include "clang/Tooling/Tooling.h"
 #include "llvm/ADT/APFloat.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Error.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Support/Process.h"
 #include "llvm/Support/Signals.h"
FormatEnum("format", llvm::cl::desc("Format for outputted docs."),
                                            "Documentation in MD format.")),
                llvm::cl::init(OutputFormatTy::yaml),
                llvm::cl::cat(ClangDocCategory));
 
 static llvm::cl::opt<bool> DoxygenOnly(
     "doxygen",
     llvm::cl::desc("Use only doxygen-style comments to generate docs."),
     llvm::cl::init(false), llvm::cl::cat(ClangDocCategory));
 
+static llvm::cl::opt<std::string>
+    ClangDocExecutorName("doc-executor", llvm::cl::desc("The name of the executor to use in clang-doc."),
+                 llvm::cl::init("all-TUs"));
+
 bool CreateDirectory(const Twine &DirName, bool ClearDirectory = false) {
   std::error_code OK;
   llvm::SmallString<128> DocsRootPath;
   if (ClearDirectory) {
     std::error_code RemoveStatus = llvm::sys::fs::remove_directories(DirName);
     if (RemoveStatus != OK) {
       llvm::errs() << "Unable to remove existing documentation directory for "
                    << DirName << ".\n";
for (auto &I : Infos.get()) {
       auto R =
           Output.try_emplace(Key, std::vector<std::unique_ptr<doc::Info>>());
       R.first->second.emplace_back(std::move(I));
     }
   });
   return Err;
 }
 
+llvm::Expected<std::unique_ptr<ToolExecutor>>
+createClangDocExecutor(int &argc, const char **argv,
+                                      llvm::cl::OptionCategory &Category) {
+  auto OptionsParser =
+      CommonOptionsParser::create(argc, argv, Category, llvm::cl::ZeroOrMore);
+  if (!OptionsParser)
+    return OptionsParser.takeError();
+  for (auto I = ToolExecutorPluginRegistry::begin(),
+            E = ToolExecutorPluginRegistry::end();
+       I != E; ++I) {
+    if (I->getName() != ClangDocExecutorName) {
+      continue;
+    }
+    std::unique_ptr<ToolExecutorPlugin> Plugin(I->instantiate());
+    llvm::Expected<std::unique_ptr<ToolExecutor>> Executor =
+        Plugin->create(*OptionsParser);
+    if (!Executor) {
+      return llvm::make_error<llvm::StringError>(
+          llvm::Twine("Failed to create '") + I->getName() +
+              "': " + llvm::toString(Executor.takeError()) + "\n",
+          llvm::inconvertibleErrorCode());
+    }
+    return std::move(*Executor);
+  }
+  return llvm::make_error<llvm::StringError>(
+      llvm::Twine("Executor \"") + ClangDocExecutorName + "\" is not registered.",
+      llvm::inconvertibleErrorCode());
+}
+
 int main(int argc, const char **argv) {
   llvm::sys::PrintStackTraceOnErrorSignal(argv[0]);
   std::error_code OK;
 
-  auto Exec = clang::tooling::createExecutorFromCommandLineArgs(
-      argc, argv, ClangDocCategory);
+  auto Exec = createClangDocExecutor(argc, argv, ClangDocCategory);
 
   if (!Exec) {
     llvm::errs() << toString(Exec.takeError()) << "\n";
     return 1;
   }
 
   // Fail early if an invalid format was provided.
   std::string Format = getFormatString();