[clangd] GlobalCompilationDatabase interface changes

Summary:
- GlobalCompilationDatabase now returns a single command (that's all we use)
- fallback flags are now part of the GlobalCompilationDatabase.
  There's a default implementation that they can optionally customize.
- this allows us to avoid invoking the fallback logic on two separate codepaths
- race on extra flags fixed by locking the mutex
- made GCD const-correct (DBGCD does have mutating methods)

Reviewers: hokein

Subscribers: klimek, cfe-commits, ilya-biryukov

Differential Revision: https://reviews.llvm.org/D40733

git-svn-id: https://llvm.org/svn/llvm-project/clang-tools-extra/trunk@319647 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 7 insertions, 11 deletions

diff --git a/unittests/clangd/ClangdTests.cpp b/unittests/clangd/ClangdTests.cpp
index 73462e8d..c8d43972 100644
--- a/unittests/clangd/ClangdTests.cpp
+++ b/unittests/clangd/ClangdTests.cpp
@@ -212,21 +212,17 @@ public:
       ExtraClangFlags.push_back("-ffreestanding");
   }
 
-  std::vector<tooling::CompileCommand>
-  getCompileCommands(PathRef File) override {
+  llvm::Optional<tooling::CompileCommand>
+  getCompileCommand(PathRef File) const override {
     if (ExtraClangFlags.empty())
-      return {};
-
-    std::vector<std::string> CommandLine;
-    CommandLine.reserve(3 + ExtraClangFlags.size());
-    CommandLine.insert(CommandLine.end(), {"clang", "-fsyntax-only"});
-    CommandLine.insert(CommandLine.end(), ExtraClangFlags.begin(),
-                       ExtraClangFlags.end());
-    CommandLine.push_back(File.str());
+      return llvm::None;
 
+    auto CommandLine = ExtraClangFlags;
+    CommandLine.insert(CommandLine.begin(), "clang");
+    CommandLine.insert(CommandLine.end(), File.str());
     return {tooling::CompileCommand(llvm::sys::path::parent_path(File),
                                     llvm::sys::path::filename(File),
-                                    CommandLine, "")};
+                                    std::move(CommandLine), "")};
   }
 
   std::vector<std::string> ExtraClangFlags;