[clangd] Rename DiagnosticsConsumer -> ClangdServer::Callbacks, and make it optional

[sammccall]

Summary

This reflects its current function better and avoids confusion with clang::DiagnosticConsumer.

The old name/constructor is left around temporarily for compatibility.
(Metagame: merging with out-of-tree changes is harder than usual this month)

[sammccall]

Document new interface and threading model of existing functions.

[merge_guards_bot]

Unit tests: fail. 62158 tests passed, 5 failed and 811 were skipped.

failed: libc++.std/language_support/cmp/cmp_partialord/partialord.pass.cpp
failed: libc++.std/language_support/cmp/cmp_strongeq/cmp.strongeq.pass.cpp
failed: libc++.std/language_support/cmp/cmp_strongord/strongord.pass.cpp
failed: libc++.std/language_support/cmp/cmp_weakeq/cmp.weakeq.pass.cpp
failed: libc++.std/language_support/cmp/cmp_weakord/weakord.pass.cpp

clang-tidy: pass.

clang-format: pass.

Build artifacts: diff.json, clang-tidy.txt, clang-format.patch, CMakeCache.txt, console-log.txt, test-results.xml

Pre-merge checks is in beta. Report issue. Please join beta or enable it for your project.

[hokein]

clang-tools-extra/clangd/ClangdServer.h

76

nit : clang-format.

163–164

nit: the doc is out-of-date now.

clang-tools-extra/clangd/unittests/ClangdTests.cpp

277

nit: maybe rename this class as well.

[merge_guards_bot]

Unit tests: fail. 62158 tests passed, 5 failed and 811 were skipped.

failed: libc++.std/language_support/cmp/cmp_partialord/partialord.pass.cpp
failed: libc++.std/language_support/cmp/cmp_strongeq/cmp.strongeq.pass.cpp
failed: libc++.std/language_support/cmp/cmp_strongord/strongord.pass.cpp
failed: libc++.std/language_support/cmp/cmp_weakeq/cmp.weakeq.pass.cpp
failed: libc++.std/language_support/cmp/cmp_weakord/weakord.pass.cpp

clang-tidy: pass.

clang-format: pass.

Build artifacts: diff.json, clang-tidy.txt, clang-format.patch, CMakeCache.txt, console-log.txt, test-results.xml

Pre-merge checks is in beta. Report issue. Please join beta or enable it for your project.

[sammccall]

clang-tools-extra/clangd/ClangdServer.h

76

this is actually a clang-format bug :-\ I'll try to fix it

clang-tools-extra/clangd/ClangdLSPServer.h

 
 class SymbolIndex;
 
 /// This class exposes ClangdServer's capabilities via Language Server Protocol.
 ///
 /// MessageHandler binds the implemented LSP methods (e.g. onInitialize) to
 /// corresponding JSON-RPC methods ("initialize").
 /// The server also supports $/cancelRequest (MessageHandler provides this).
-class ClangdLSPServer : private DiagnosticsConsumer {
+class ClangdLSPServer : private ClangdServer::Callbacks {
 public:
   /// If \p CompileCommandsDir has a value, compile_commands.json will be
   /// loaded only from \p CompileCommandsDir. Otherwise, clangd will look
   /// for compile_commands.json in all parent directories of each file.
   /// If UseDirBasedCDB is false, compile commands are not read from disk.
   // FIXME: Clean up signature around CDBs.
   ClangdLSPServer(Transport &Transp, const FileSystemProvider &FSProvider,
                   const clangd::CodeCompleteOptions &CCOpts,
                   llvm::Optional<Path> CompileCommandsDir, bool UseDirBasedCDB,
                   llvm::Optional<OffsetEncoding> ForcedOffsetEncoding,
                   const ClangdServer::Options &Opts);
   /// The destructor blocks on any outstanding background tasks.
   ~ClangdLSPServer();
 
   /// Run LSP server loop, communicating with the Transport provided in the
   /// constructor. This method must not be executed more than once.
   ///
   /// \return Whether we shut down cleanly with a 'shutdown' -> 'exit' sequence.
   bool run();
 
 private:
-  // Implement DiagnosticsConsumer.
+  // Implement ClangdServer::Callbacks.
   void onDiagnosticsReady(PathRef File, std::vector<Diag> Diagnostics) override;
   void onFileUpdated(PathRef File, const TUStatus &Status) override;
   void
   onHighlightingsReady(PathRef File,
                        std::vector<HighlightingToken> Highlightings) override;
   void onBackgroundIndexProgress(const BackgroundQueue::Stats &Stats) override;
 
   // LSP methods. Notifications have signature void(const Params&).

clang-tools-extra/clangd/ClangdLSPServer.cpp

CDB.emplace(BaseCDB.get(), Params.initializationOptions.fallbackFlags,
     // Switch caller's context with LSPServer's background context. Since we
     // rather want to propagate information from LSPServer's context into the
     // Server, CDB, etc.
     WithContext MainContext(BackgroundContext.clone());
     llvm::Optional<WithContextValue> WithOffsetEncoding;
     if (NegotiatedOffsetEncoding)
       WithOffsetEncoding.emplace(kCurrentOffsetEncoding,
                                  *NegotiatedOffsetEncoding);
-    Server.emplace(*CDB, FSProvider, static_cast<DiagnosticsConsumer &>(*this),
-                   ClangdServerOpts);
+    Server.emplace(*CDB, FSProvider, ClangdServerOpts,
+                   static_cast<ClangdServer::Callbacks *>(this));
   }
   applyConfiguration(Params.initializationOptions.ConfigSettings);
 
   CCOpts.EnableSnippets = Params.capabilities.CompletionSnippets;
   CCOpts.IncludeFixIts = Params.capabilities.CompletionFixes;
   if (!CCOpts.BundleOverloads.hasValue())
     CCOpts.BundleOverloads = Params.capabilities.HasSignatureHelp;
   DiagOpts.EmbedFixesInDiagnostics = Params.capabilities.DiagnosticFixes;

clang-tools-extra/clangd/ClangdServer.h

 #include <future>
 #include <string>
 #include <type_traits>
 #include <utility>
 
 namespace clang {
 namespace clangd {
 
-// FIXME: find a better name.
-class DiagnosticsConsumer {
-public:
-  virtual ~DiagnosticsConsumer() = default;
-
-  /// Called by ClangdServer when \p Diagnostics for \p File are ready.
-  virtual void onDiagnosticsReady(PathRef File,
-                                  std::vector<Diag> Diagnostics) = 0;
-  /// Called whenever the file status is updated.
-  virtual void onFileUpdated(PathRef File, const TUStatus &Status){};
-
-  /// Called by ClangdServer when some \p Highlightings for \p File are ready.
-  virtual void
-  onHighlightingsReady(PathRef File,
-                       std::vector<HighlightingToken> Highlightings) {}
-
-  // Called when background indexing tasks are enqueued, started, or completed.
-  virtual void onBackgroundIndexProgress(const BackgroundQueue::Stats &Stats) {}
-};
-
 /// When set, used by ClangdServer to get clang-tidy options for each particular
 /// file. Must be thread-safe. We use this instead of ClangTidyOptionsProvider
 /// to allow reading tidy configs from the VFS used for parsing.
 using ClangTidyOptionsBuilder = std::function<tidy::ClangTidyOptions(
     llvm::vfs::FileSystem &, llvm::StringRef /*File*/)>;
 
 /// Manages a collection of source files and derived data (ASTs, indexes),
 /// and provides language-aware features such as code completion.
 ///
 /// The primary client is ClangdLSPServer which exposes these features via
 /// the Language Server protocol. ClangdServer may also be embedded directly,
 /// though its API is not stable over time.
 ///
 /// ClangdServer should be used from a single thread. Many potentially-slow
 /// operations have asynchronous APIs and deliver their results on another
 /// thread.
 /// Such operations support cancellation: if the caller sets up a cancelable
 /// context, many operations will notice cancellation and fail early.
 /// (ClangdLSPServer uses this to implement $/cancelRequest).
 class ClangdServer {
 public:
+  /// Interface with hooks for users of ClangdServer to be notified of events.
+  class Callbacks {
+  public:
+    virtual ~Callbacks() = default;
+
+    /// Called by ClangdServer when \p Diagnostics for \p File are ready.
+    /// May be called concurrently for separate files, not for a single file.
+    virtual void onDiagnosticsReady(PathRef File,
+                                    std::vector<Diag> Diagnostics) {}
+    /// Called whenever the file status is updated.
+    /// May be called concurrently for separate files, not for a single file.
+    virtual void onFileUpdated(PathRef File, const TUStatus &Status){};
+
+    /// Called by ClangdServer when some \p Highlightings for \p File are ready.
+    /// May be called concurrently for separate files, not for a single file.
+    virtual void
+    onHighlightingsReady(PathRef File,
+                         std::vector<HighlightingToken> Highlightings) {}
+
+    /// Called when background indexing tasks are enqueued/started/completed.
+    /// Not called concurrently.
+    virtual void
+    onBackgroundIndexProgress(const BackgroundQueue::Stats &Stats) {}
+  };
+
   struct Options {
     /// To process requests asynchronously, ClangdServer spawns worker threads.
     /// If this is zero, no threads are spawned. All work is done on the calling
     /// thread, and callbacks are invoked before "async" functions return.
     unsigned AsyncThreadsCount = getDefaultAsyncThreadsCount();
 
     /// AST caching policy. The default is to keep up to 3 ASTs in memory.
     ASTRetentionPolicy RetentionPolicy;
public:
   static Options optsForTest();
 
   /// Creates a new ClangdServer instance.
   ///
   /// ClangdServer uses \p CDB to obtain compilation arguments for parsing. Note
   /// that ClangdServer only obtains compilation arguments once for each newly
   /// added file (i.e., when processing a first call to addDocument) and reuses
   /// those arguments for subsequent reparses. However, ClangdServer will check
   /// if compilation arguments changed on calls to forceReparse().
-  ///
-  /// After each parsing request finishes, ClangdServer reports diagnostics to
-  /// \p DiagConsumer. Note that a callback to \p DiagConsumer happens on a
-  /// worker thread. Therefore, instances of \p DiagConsumer must properly
-  /// synchronize access to shared state.
   ClangdServer(const GlobalCompilationDatabase &CDB,
-               const FileSystemProvider &FSProvider,
-               DiagnosticsConsumer &DiagConsumer, const Options &Opts);
+               const FileSystemProvider &FSProvider, const Options &Opts,
+               Callbacks *Callbacks = nullptr);
+
+  // FIXME: remove this compatibility alias.
+  ClangdServer(const GlobalCompilationDatabase &CDB,
+               const FileSystemProvider &FSProvider, Callbacks &Callbacks,
+               const Options &Opts)
+      : ClangdServer(CDB, FSProvider, Opts, &Callbacks) {}
 
   /// Add a \p File to the list of tracked C++ files or update the contents if
   /// \p File is already tracked. Also schedules parsing of the AST for it on a
   /// separate thread. When the parsing is complete, DiagConsumer passed in
   /// constructor will receive onDiagnosticsReady callback.
   void addDocument(PathRef File, StringRef Contents,
                    WantDiagnostics WD = WantDiagnostics::Auto);
 
private:
 
   llvm::Optional<std::string> WorkspaceRoot;
   // WorkScheduler has to be the last member, because its destructor has to be
   // called before all other members to stop the worker thread that references
   // ClangdServer.
   TUScheduler WorkScheduler;
 };
 
+// FIXME: Remove this compatibility alias.
+using DiagnosticsConsumer = ClangdServer::Callbacks;
+
 } // namespace clangd
 } // namespace clang
 
 #endif

clang-tools-extra/clangd/ClangdServer.cpp

 #include <type_traits>
 
 namespace clang {
 namespace clangd {
 namespace {
 
 // Update the FileIndex with new ASTs and plumb the diagnostics responses.
 struct UpdateIndexCallbacks : public ParsingCallbacks {
-  UpdateIndexCallbacks(FileIndex *FIndex, DiagnosticsConsumer &DiagConsumer,
+  UpdateIndexCallbacks(FileIndex *FIndex,
+                       ClangdServer::Callbacks *ServerCallbacks,
                        bool SemanticHighlighting)
-      : FIndex(FIndex), DiagConsumer(DiagConsumer),
+      : FIndex(FIndex), ServerCallbacks(ServerCallbacks),
         SemanticHighlighting(SemanticHighlighting) {}
 
   void onPreambleAST(PathRef Path, ASTContext &Ctx,
                      std::shared_ptr<clang::Preprocessor> PP,
                      const CanonicalIncludes &CanonIncludes) override {
     if (FIndex)
       FIndex->updatePreamble(Path, Ctx, std::move(PP), CanonIncludes);
   }
 
   void onMainAST(PathRef Path, ParsedAST &AST, PublishFn Publish) override {
     if (FIndex)
       FIndex->updateMain(Path, AST);
 
     std::vector<Diag> Diagnostics = AST.getDiagnostics();
     std::vector<HighlightingToken> Highlightings;
     if (SemanticHighlighting)
       Highlightings = getSemanticHighlightings(AST);
 
+    if (ServerCallbacks)
       Publish([&]() {
-      DiagConsumer.onDiagnosticsReady(Path, std::move(Diagnostics));
+        ServerCallbacks->onDiagnosticsReady(Path, std::move(Diagnostics));
         if (SemanticHighlighting)
-        DiagConsumer.onHighlightingsReady(Path, std::move(Highlightings));
+          ServerCallbacks->onHighlightingsReady(Path, std::move(Highlightings));
       });
   }
 
   void onFailedAST(PathRef Path, std::vector<Diag> Diags,
                    PublishFn Publish) override {
-    Publish([&]() { DiagConsumer.onDiagnosticsReady(Path, Diags); });
+    if (ServerCallbacks)
+      Publish([&]() { ServerCallbacks->onDiagnosticsReady(Path, Diags); });
   }
 
   void onFileUpdated(PathRef File, const TUStatus &Status) override {
-    DiagConsumer.onFileUpdated(File, Status);
+    if (ServerCallbacks)
+      ServerCallbacks->onFileUpdated(File, Status);
   }
 
 private:
   FileIndex *FIndex;
-  DiagnosticsConsumer &DiagConsumer;
+  ClangdServer::Callbacks *ServerCallbacks;
   bool SemanticHighlighting;
 };
 } // namespace
 
 ClangdServer::Options ClangdServer::optsForTest() {
   ClangdServer::Options Opts;
   Opts.UpdateDebounce = std::chrono::steady_clock::duration::zero(); // Faster!
   Opts.StorePreamblesInMemory = true;
   Opts.AsyncThreadsCount = 4; // Consistent!
   Opts.SemanticHighlighting = true;
   return Opts;
 }
 
 ClangdServer::ClangdServer(const GlobalCompilationDatabase &CDB,
                            const FileSystemProvider &FSProvider,
-                           DiagnosticsConsumer &DiagConsumer,
-                           const Options &Opts)
+                           const Options &Opts, Callbacks *Callbacks)
     : FSProvider(FSProvider),
       DynamicIdx(Opts.BuildDynamicSymbolIndex
                      ? new FileIndex(Opts.HeavyweightDynamicSymbolIndex)
                      : nullptr),
       GetClangTidyOptions(Opts.GetClangTidyOptions),
       SuggestMissingIncludes(Opts.SuggestMissingIncludes),
       CrossFileRename(Opts.CrossFileRename), TweakFilter(Opts.TweakFilter),
       WorkspaceRoot(Opts.WorkspaceRoot),
       // Pass a callback into `WorkScheduler` to extract symbols from a newly
       // parsed file and rebuild the file index synchronously each time an AST
       // is parsed.
       // FIXME(ioeric): this can be slow and we may be able to index on less
       // critical paths.
-      WorkScheduler(
-          CDB, Opts.AsyncThreadsCount, Opts.StorePreamblesInMemory,
-          std::make_unique<UpdateIndexCallbacks>(DynamicIdx.get(), DiagConsumer,
-                                                 Opts.SemanticHighlighting),
+      WorkScheduler(CDB, Opts.AsyncThreadsCount, Opts.StorePreamblesInMemory,
+                    std::make_unique<UpdateIndexCallbacks>(
+                        DynamicIdx.get(), Callbacks, Opts.SemanticHighlighting),
                     Opts.UpdateDebounce, Opts.RetentionPolicy) {
   // Adds an index to the stack, at higher priority than existing indexes.
   auto AddIndex = [&](SymbolIndex *Idx) {
     if (this->Index != nullptr) {
       MergedIdx.push_back(std::make_unique<MergedIndex>(Idx, this->Index));
       this->Index = MergedIdx.back().get();
     } else {
       this->Index = Idx;
     }
   };
   if (Opts.StaticIndex)
     AddIndex(Opts.StaticIndex);
   if (Opts.BackgroundIndex) {
     BackgroundIdx = std::make_unique<BackgroundIndex>(
         Context::current().clone(), FSProvider, CDB,
         BackgroundIndexStorage::createDiskBackedStorageFactory(
             [&CDB](llvm::StringRef File) { return CDB.getProjectInfo(File); }),
         std::max(Opts.AsyncThreadsCount, 1u),
-        [&DiagConsumer](BackgroundQueue::Stats S) {
-          DiagConsumer.onBackgroundIndexProgress(S);
+        [Callbacks](BackgroundQueue::Stats S) {
+          if (Callbacks)
+            Callbacks->onBackgroundIndexProgress(S);
         });
     AddIndex(BackgroundIdx.get());
   }
   if (DynamicIdx)
     AddIndex(DynamicIdx.get());
 }
 
 void ClangdServer::addDocument(PathRef File, llvm::StringRef Contents,

clang-tools-extra/clangd/unittests/ClangdTests.cpp

bool diagsContainErrors(const std::vector<Diag> &Diagnostics) {
   for (auto D : Diagnostics) {
     if (D.Severity == DiagnosticsEngine::Error ||
         D.Severity == DiagnosticsEngine::Fatal)
       return true;
   }
   return false;
 }
 
-class ErrorCheckingDiagConsumer : public DiagnosticsConsumer {
+class ErrorCheckingCallbacks : public ClangdServer::Callbacks {
 public:
   void onDiagnosticsReady(PathRef File,
                           std::vector<Diag> Diagnostics) override {
     bool HadError = diagsContainErrors(Diagnostics);
     std::lock_guard<std::mutex> Lock(Mutex);
     HadErrorInLastDiags = HadError;
   }
 
   bool hadErrorInLastDiags() {
     std::lock_guard<std::mutex> Lock(Mutex);
     return HadErrorInLastDiags;
   }
 
 private:
   std::mutex Mutex;
   bool HadErrorInLastDiags = false;
 };
 
 /// For each file, record whether the last published diagnostics contained at
 /// least one error.
-class MultipleErrorCheckingDiagConsumer : public DiagnosticsConsumer {
+class MultipleErrorCheckingCallbacks : public ClangdServer::Callbacks {
 public:
   void onDiagnosticsReady(PathRef File,
                           std::vector<Diag> Diagnostics) override {
     bool HadError = diagsContainErrors(Diagnostics);
 
     std::lock_guard<std::mutex> Lock(Mutex);
     LastDiagsHadError[File] = HadError;
   }

 
 class ClangdVFSTest : public ::testing::Test {
 protected:
   std::string parseSourceAndDumpAST(
       PathRef SourceFileRelPath, llvm::StringRef SourceContents,
       std::vector<std::pair<PathRef, llvm::StringRef>> ExtraFiles = {},
       bool ExpectErrors = false) {
     MockFSProvider FS;
-    ErrorCheckingDiagConsumer DiagConsumer;
+    ErrorCheckingCallbacks DiagConsumer;
     MockCompilationDatabase CDB;
-    ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+    ClangdServer Server(CDB, FS, ClangdServer::optsForTest(), &DiagConsumer);
     for (const auto &FileWithContents : ExtraFiles)
       FS.Files[testPath(FileWithContents.first)] = FileWithContents.second;
 
     auto SourceFilename = testPath(SourceFileRelPath);
     Server.addDocument(SourceFilename, SourceContents);
     auto Result = dumpASTWithoutMemoryLocs(Server, SourceFilename);
     EXPECT_TRUE(Server.blockUntilIdleForTest()) << "Waiting for diagnostics";
     EXPECT_EQ(ExpectErrors, DiagConsumer.hadErrorInLastDiags());
)cpp";
   parseSourceAndDumpAST("foo.cpp", SourceContents, {{"foo.h", ""}},
                         /*ExpectErrors=*/true);
   parseSourceAndDumpAST("foo.cpp", SourceContents, {{"foo.h", "int a;"}},
                         /*ExpectErrors=*/false);
 }
 
 TEST_F(ClangdVFSTest, Reparse) {
   MockFSProvider FS;
-  ErrorCheckingDiagConsumer DiagConsumer;
+  ErrorCheckingCallbacks DiagConsumer;
   MockCompilationDatabase CDB;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest(), &DiagConsumer);
 
   const auto SourceContents = R"cpp(
 #include "foo.h"
 int b = a;
 )cpp";
 
   auto FooCpp = testPath("foo.cpp");
 
)cpp";
   EXPECT_FALSE(DiagConsumer.hadErrorInLastDiags());
 
   EXPECT_EQ(DumpParse1, DumpParse2);
   EXPECT_NE(DumpParse1, DumpParseEmpty);
 }
 
 TEST_F(ClangdVFSTest, ReparseOnHeaderChange) {
   MockFSProvider FS;
-  ErrorCheckingDiagConsumer DiagConsumer;
+  ErrorCheckingCallbacks DiagConsumer;
   MockCompilationDatabase CDB;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest(), &DiagConsumer);
 
   const auto SourceContents = R"cpp(
 #include "foo.h"
 int b = a;
 )cpp";
 
   auto FooCpp = testPath("foo.cpp");
   auto FooH = testPath("foo.h");
TEST_F(ClangdVFSTest, PropagatesContexts) {
   static Key<int> Secret;
   struct FSProvider : public FileSystemProvider {
     IntrusiveRefCntPtr<llvm::vfs::FileSystem> getFileSystem() const override {
       Got = Context::current().getExisting(Secret);
       return buildTestFS({});
     }
     mutable int Got;
   } FS;
-  struct DiagConsumer : public DiagnosticsConsumer {
+  struct Callbacks : public ClangdServer::Callbacks {
     void onDiagnosticsReady(PathRef File,
                             std::vector<Diag> Diagnostics) override {
       Got = Context::current().getExisting(Secret);
     }
     int Got;
-  } DiagConsumer;
+  } Callbacks;
   MockCompilationDatabase CDB;
 
   // Verify that the context is plumbed to the FS provider and diagnostics.
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest(), &Callbacks);
   {
     WithContextValue Entrypoint(Secret, 42);
     Server.addDocument(testPath("foo.cpp"), "void main(){}");
   }
   ASSERT_TRUE(Server.blockUntilIdleForTest());
   EXPECT_EQ(FS.Got, 42);
-  EXPECT_EQ(DiagConsumer.Got, 42);
+  EXPECT_EQ(Callbacks.Got, 42);
 }
 
 // Only enable this test on Unix
 #ifdef LLVM_ON_UNIX
 TEST_F(ClangdVFSTest, SearchLibDir) {
   // Checks that searches for GCC installation is done through vfs.
   MockFSProvider FS;
-  ErrorCheckingDiagConsumer DiagConsumer;
+  ErrorCheckingCallbacks DiagConsumer;
   MockCompilationDatabase CDB;
   CDB.ExtraClangFlags.insert(CDB.ExtraClangFlags.end(),
                              {"-xc++", "-target", "x86_64-linux-unknown",
                               "-m64", "--gcc-toolchain=/randomusr",
                               "-stdlib=libstdc++"});
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest(), &DiagConsumer);
 
   // Just a random gcc version string
   SmallString<8> Version("4.9.3");
 
   // A lib dir for gcc installation
   SmallString<64> LibDir("/randomusr/lib/gcc/x86_64-linux-gnu");
   llvm::sys::path::append(LibDir, Version);
 

 )cpp";
   runAddDocument(Server, FooCpp, SourceContentsWithError);
   EXPECT_TRUE(DiagConsumer.hadErrorInLastDiags());
 }
 #endif // LLVM_ON_UNIX
 
 TEST_F(ClangdVFSTest, ForceReparseCompileCommand) {
   MockFSProvider FS;
-  ErrorCheckingDiagConsumer DiagConsumer;
+  ErrorCheckingCallbacks DiagConsumer;
   MockCompilationDatabase CDB;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest(), &DiagConsumer);
 
   auto FooCpp = testPath("foo.cpp");
   const auto SourceContents1 = R"cpp(
 template <class T>
 struct foo { T x; };
 )cpp";
   const auto SourceContents2 = R"cpp(
 template <class T>
)cpp";
   runAddDocument(Server, FooCpp, SourceContents1);
   EXPECT_FALSE(DiagConsumer.hadErrorInLastDiags());
   runAddDocument(Server, FooCpp, SourceContents2);
   EXPECT_FALSE(DiagConsumer.hadErrorInLastDiags());
 }
 
 TEST_F(ClangdVFSTest, ForceReparseCompileCommandDefines) {
   MockFSProvider FS;
-  ErrorCheckingDiagConsumer DiagConsumer;
+  ErrorCheckingCallbacks DiagConsumer;
   MockCompilationDatabase CDB;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest(), &DiagConsumer);
 
   auto FooCpp = testPath("foo.cpp");
   const auto SourceContents = R"cpp(
 #ifdef WITH_ERROR
 this
 #endif
 
 int main() { return 0; }

 )cpp");
 
   Annotations BazSource(R"cpp(
 int hello;
 )cpp");
 
   MockFSProvider FS;
   MockCompilationDatabase CDB;
-  MultipleErrorCheckingDiagConsumer DiagConsumer;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  MultipleErrorCheckingCallbacks DiagConsumer;
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest(), &DiagConsumer);
 
   auto FooCpp = testPath("foo.cpp");
   auto BarCpp = testPath("bar.cpp");
   auto BazCpp = testPath("baz.cpp");
 
   FS.Files[FooCpp] = "";
   FS.Files[BarCpp] = "";
   FS.Files[BazCpp] = "";
)cpp");
 
   Locations = runLocateSymbolAt(Server, FooCpp, FooSource.point());
   EXPECT_TRUE(bool(Locations));
   EXPECT_THAT(*Locations, ElementsAre(DeclAt(FooCpp, FooSource.range("two"))));
 }
 
 TEST_F(ClangdVFSTest, MemoryUsage) {
   MockFSProvider FS;
-  ErrorCheckingDiagConsumer DiagConsumer;
+  ErrorCheckingCallbacks DiagConsumer;
   MockCompilationDatabase CDB;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest(), &DiagConsumer);
 
   Path FooCpp = testPath("foo.cpp");
   const auto SourceContents = R"cpp(
 struct Something {
   int method();
 };
 )cpp";
   Path BarCpp = testPath("bar.cpp");
)cpp";
 
   Server.removeDocument(BarCpp);
   ASSERT_TRUE(Server.blockUntilIdleForTest());
   EXPECT_THAT(Server.getUsedBytesPerFile(), IsEmpty());
 }
 
 TEST_F(ClangdVFSTest, InvalidCompileCommand) {
   MockFSProvider FS;
-  ErrorCheckingDiagConsumer DiagConsumer;
+  ErrorCheckingCallbacks DiagConsumer;
   MockCompilationDatabase CDB;
 
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest(), &DiagConsumer);
 
   auto FooCpp = testPath("foo.cpp");
   // clang cannot create CompilerInvocation if we pass two files in the
   // CompileCommand. We pass the file in ExtraFlags once and CDB adds another
   // one in getCompileCommand().
   CDB.ExtraClangFlags.push_back(FooCpp);
 
   // Clang can't parse command args in that case, but we shouldn't crash.
)cpp";
   }
 
   struct FileStat {
     unsigned HitsWithoutErrors = 0;
     unsigned HitsWithErrors = 0;
     bool HadErrorsInLastDiags = false;
   };
 
-  class TestDiagConsumer : public DiagnosticsConsumer {
+  class TestDiagConsumer : public ClangdServer::Callbacks {
   public:
     TestDiagConsumer() : Stats(FilesCount, FileStat()) {}
 
     void onDiagnosticsReady(PathRef File,
                             std::vector<Diag> Diagnostics) override {
       StringRef FileIndexStr = llvm::sys::path::stem(File);
       ASSERT_TRUE(FileIndexStr.consume_front("Foo"));
 
)cpp";
   std::vector<RequestStats> ReqStats;
   ReqStats.reserve(FilesCount);
   for (unsigned FileIndex = 0; FileIndex < FilesCount; ++FileIndex)
     ReqStats.emplace_back();
 
   TestDiagConsumer DiagConsumer;
   {
     MockCompilationDatabase CDB;
-    ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+    ClangdServer Server(CDB, FS, ClangdServer::optsForTest(), &DiagConsumer);
 
     // Prepare some random distributions for the test.
     std::random_device RandGen;
 
     std::uniform_int_distribution<unsigned> FileIndexDist(0, FilesCount - 1);
     // Pass a text that contains compiler errors to addDocument in about 20% of
     // all requests.
     std::bernoulli_distribution ShouldHaveErrorsDist(0.2);
for (unsigned I = 0; I < FilesCount; ++I) {
     }
 
     ASSERT_LE(Stats[I].HitsWithErrors, ReqStats[I].RequestsWithErrors);
     ASSERT_LE(Stats[I].HitsWithoutErrors, ReqStats[I].RequestsWithoutErrors);
   }
 }
 
 TEST_F(ClangdThreadingTest, NoConcurrentDiagnostics) {
-  class NoConcurrentAccessDiagConsumer : public DiagnosticsConsumer {
+  class NoConcurrentAccessDiagConsumer : public ClangdServer::Callbacks {
   public:
     std::atomic<int> Count = {0};
 
     NoConcurrentAccessDiagConsumer(std::promise<void> StartSecondReparse)
         : StartSecondReparse(std::move(StartSecondReparse)) {}
 
     void onDiagnosticsReady(PathRef, std::vector<Diag>) override {
       ++Count;
)cpp";
   MockFSProvider FS;
   FS.Files[FooCpp] = "";
 
   std::promise<void> StartSecondPromise;
   std::future<void> StartSecond = StartSecondPromise.get_future();
 
   NoConcurrentAccessDiagConsumer DiagConsumer(std::move(StartSecondPromise));
   MockCompilationDatabase CDB;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest(), &DiagConsumer);
   Server.addDocument(FooCpp, SourceContentsWithErrors);
   StartSecond.wait();
   Server.addDocument(FooCpp, SourceContentsWithoutErrors);
   ASSERT_TRUE(Server.blockUntilIdleForTest()) << "Waiting for diagnostics";
   ASSERT_EQ(DiagConsumer.Count, 2); // Sanity check - we actually ran both?
 }
 
 TEST_F(ClangdVFSTest, FormatCode) {
   MockFSProvider FS;
-  ErrorCheckingDiagConsumer DiagConsumer;
+  ErrorCheckingCallbacks DiagConsumer;
   MockCompilationDatabase CDB;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest(), &DiagConsumer);
 
   auto Path = testPath("foo.cpp");
   std::string Code = R"cpp(
 #include "x.h"
 #include "y.h"
 
 void f(  )  {}
 )cpp";
)cpp";
   EXPECT_TRUE(static_cast<bool>(Replaces));
   auto Changed = tooling::applyAllReplacements(Code, *Replaces);
   EXPECT_TRUE(static_cast<bool>(Changed));
   EXPECT_EQ(Expected, *Changed);
 }
 
 TEST_F(ClangdVFSTest, ChangedHeaderFromISystem) {
   MockFSProvider FS;
-  ErrorCheckingDiagConsumer DiagConsumer;
+  ErrorCheckingCallbacks DiagConsumer;
   MockCompilationDatabase CDB;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest(), &DiagConsumer);
 
   auto SourcePath = testPath("source/foo.cpp");
   auto HeaderPath = testPath("headers/foo.h");
   FS.Files[HeaderPath] = "struct X { int bar; };";
   Annotations Code(R"cpp(
     #include "foo.h"
 
     int main() {
public:
 
     // If relative paths are used, they are resolved with testPath().
     llvm::StringMap<std::string> Files;
     llvm::StringMap<unsigned> &CountStats;
   };
 
   llvm::StringMap<unsigned> CountStats;
   ListenStatsFSProvider FS(CountStats);
-  ErrorCheckingDiagConsumer DiagConsumer;
+  ErrorCheckingCallbacks DiagConsumer;
   MockCompilationDatabase CDB;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest(), &DiagConsumer);
 
   auto SourcePath = testPath("foo.cpp");
   auto HeaderPath = testPath("foo.h");
   FS.Files[HeaderPath] = "struct TestSym {};";
   Annotations Code(R"cpp(
     #include "foo.h"
 
     int main() {
TEST(ClangdTests, PreambleVFSStatCache) {
   EXPECT_EQ(CountStats["foo.h"], Before);
   EXPECT_THAT(Completions,
               ElementsAre(Field(&CodeCompletion::Name, "TestSym")));
 }
 #endif
 
 TEST_F(ClangdVFSTest, FallbackWhenPreambleIsNotReady) {
   MockFSProvider FS;
-  ErrorCheckingDiagConsumer DiagConsumer;
+  ErrorCheckingCallbacks DiagConsumer;
   MockCompilationDatabase CDB;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest(), &DiagConsumer);
 
   auto FooCpp = testPath("foo.cpp");
   Annotations Code(R"cpp(
     namespace ns { int xyz; }
     using namespace ns;
     int main() {
        xy^
     })cpp");
TEST_F(ClangdVFSTest, FallbackWhenPreambleIsNotReady) {
   EXPECT_THAT(
       cantFail(runCodeComplete(Server, FooCpp, Code.point(), Opts)).Completions,
       ElementsAre(AllOf(Field(&CodeCompletion::Name, "xyz"),
                         Field(&CodeCompletion::Scope, ""))));
 }
 
 TEST_F(ClangdVFSTest, FallbackWhenWaitingForCompileCommand) {
   MockFSProvider FS;
-  ErrorCheckingDiagConsumer DiagConsumer;
+  ErrorCheckingCallbacks DiagConsumer;
   // Returns compile command only when notified.
   class DelayedCompilationDatabase : public GlobalCompilationDatabase {
   public:
     DelayedCompilationDatabase(Notification &CanReturnCommand)
         : CanReturnCommand(CanReturnCommand) {}
 
     llvm::Optional<tooling::CompileCommand>
     getCompileCommand(PathRef File) const override {
public:
     std::vector<std::string> ExtraClangFlags;
 
   private:
     Notification &CanReturnCommand;
   };
 
   Notification CanReturnCommand;
   DelayedCompilationDatabase CDB(CanReturnCommand);
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest(), &DiagConsumer);
 
   auto FooCpp = testPath("foo.cpp");
   Annotations Code(R"cpp(
     namespace ns { int xyz; }
     using namespace ns;
     int main() {
        xy^
     })cpp");

clang-tools-extra/clangd/unittests/CodeCompleteTests.cpp

 using ::testing::Contains;
 using ::testing::ElementsAre;
 using ::testing::Field;
 using ::testing::HasSubstr;
 using ::testing::IsEmpty;
 using ::testing::Not;
 using ::testing::UnorderedElementsAre;
 
-class IgnoreDiagnostics : public DiagnosticsConsumer {
-  void onDiagnosticsReady(PathRef File,
-                          std::vector<Diag> Diagnostics) override {}
-};
-
 // GMock helpers for matching completion items.
 MATCHER_P(Named, Name, "") { return arg.Name == Name; }
 MATCHER_P(NameStartsWith, Prefix, "") {
   return llvm::StringRef(arg.Name).startswith(Prefix);
 }
 MATCHER_P(Scope, S, "") { return arg.Scope == S; }
 MATCHER_P(Qualifier, Q, "") { return arg.RequiredQualifier == Q; }
 MATCHER_P(Labeled, Label, "") {

 CodeCompleteResult completions(llvm::StringRef Text,
                                std::vector<Symbol> IndexSymbols = {},
                                clangd::CodeCompleteOptions Opts = {},
                                PathRef FilePath = "foo.cpp") {
   MockFSProvider FS;
   MockCompilationDatabase CDB;
   // To make sure our tests for completiopns inside templates work on Windows.
   CDB.ExtraClangFlags = {"-fno-delayed-template-parsing"};
-  IgnoreDiagnostics DiagConsumer;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest());
   return completions(Server, Text, std::move(IndexSymbols), std::move(Opts),
                      FilePath);
 }
 
 // Builds a server and runs code completion.
 // If IndexSymbols is non-empty, an index will be built and passed to opts.
 CodeCompleteResult completionsNoCompile(llvm::StringRef Text,
                                         std::vector<Symbol> IndexSymbols = {},
TEST(CompletionTest, IncludeInsertionPreprocessorIntegrationTests) {
   MockFSProvider FS;
   MockCompilationDatabase CDB;
   std::string Subdir = testPath("sub");
   std::string SearchDirArg = (Twine("-I") + Subdir).str();
   CDB.ExtraClangFlags = {SearchDirArg.c_str()};
   std::string BarHeader = testPath("sub/bar.h");
   FS.Files[BarHeader] = "";
 
-  IgnoreDiagnostics DiagConsumer;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest());
   auto BarURI = URI::create(BarHeader).toString();
   Symbol Sym = cls("ns::X");
   Sym.CanonicalDeclaration.FileURI = BarURI.c_str();
   Sym.IncludeHeaders.emplace_back(BarURI, 1);
   // Shoten include path based on search directory and insert.
   auto Results = completions(Server,
                              R"cpp(
           int main() { ns::^ }
TEST(CompletionTest, IncludeInsertionPreprocessorIntegrationTests) {
   EXPECT_THAT(Results.Completions, ElementsAre(AllOf(Named("X"), Labeled("X"),
                                                      Not(InsertInclude()))));
 }
 
 TEST(CompletionTest, NoIncludeInsertionWhenDeclFoundInFile) {
   MockFSProvider FS;
   MockCompilationDatabase CDB;
 
-  IgnoreDiagnostics DiagConsumer;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest());
   Symbol SymX = cls("ns::X");
   Symbol SymY = cls("ns::Y");
   std::string BarHeader = testPath("bar.h");
   auto BarURI = URI::create(BarHeader).toString();
   SymX.CanonicalDeclaration.FileURI = BarURI.c_str();
   SymY.CanonicalDeclaration.FileURI = BarURI.c_str();
   SymX.IncludeHeaders.emplace_back("<bar>", 1);
   SymY.IncludeHeaders.emplace_back("<bar>", 1);
TEST(CompletionTest, NoIncludeInsertionWhenDeclFoundInFile) {
   EXPECT_THAT(Results.Completions,
               ElementsAre(AllOf(Named("X"), Not(InsertInclude())),
                           AllOf(Named("Y"), Not(InsertInclude()))));
 }
 
 TEST(CompletionTest, IndexSuppressesPreambleCompletions) {
   MockFSProvider FS;
   MockCompilationDatabase CDB;
-  IgnoreDiagnostics DiagConsumer;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest());
 
   FS.Files[testPath("bar.h")] =
       R"cpp(namespace ns { struct preamble { int member; }; })cpp";
   auto File = testPath("foo.cpp");
   Annotations Test(R"cpp(
       #include "bar.h"
       namespace ns { int local; }
       void f() { ns::^; }
auto Results = completions(R"cpp(
     )cpp")
                      .Completions;
   EXPECT_THAT(Results, ElementsAre(Named("ifndef")));
 }
 
 TEST(CompletionTest, DynamicIndexIncludeInsertion) {
   MockFSProvider FS;
   MockCompilationDatabase CDB;
-  IgnoreDiagnostics DiagConsumer;
   ClangdServer::Options Opts = ClangdServer::optsForTest();
   Opts.BuildDynamicSymbolIndex = true;
-  ClangdServer Server(CDB, FS, DiagConsumer, Opts);
+  ClangdServer Server(CDB, FS, Opts);
 
   FS.Files[testPath("foo_header.h")] = R"cpp(
     #pragma once
     struct Foo {
        // Member doc
        int foo();
     };
   )cpp";
TEST(CompletionTest, DynamicIndexIncludeInsertion) {
   EXPECT_THAT(completions(Server, "Foo^ foo;").Completions,
               ElementsAre(AllOf(Named("Foo"), HasInclude("\"foo_header.h\""),
                                 InsertInclude())));
 }
 
 TEST(CompletionTest, DynamicIndexMultiFile) {
   MockFSProvider FS;
   MockCompilationDatabase CDB;
-  IgnoreDiagnostics DiagConsumer;
   auto Opts = ClangdServer::optsForTest();
   Opts.BuildDynamicSymbolIndex = true;
-  ClangdServer Server(CDB, FS, DiagConsumer, Opts);
+  ClangdServer Server(CDB, FS, Opts);
 
   FS.Files[testPath("foo.h")] = R"cpp(
       namespace ns { class XYZ {}; void foo(int x) {} }
   )cpp";
   runAddDocument(Server, testPath("foo.cpp"), R"cpp(
       #include "foo.h"
   )cpp");
 
EXPECT_THAT(
       Contains(AllOf(Named("bar"), Doc("Doxygen comment.\n\\param int a"))));
   EXPECT_THAT(Results.Completions,
               Contains(AllOf(Named("baz"), Doc("Multi-line\nblock comment"))));
 }
 
 TEST(CompletionTest, CommentsFromSystemHeaders) {
   MockFSProvider FS;
   MockCompilationDatabase CDB;
-  IgnoreDiagnostics DiagConsumer;
 
   auto Opts = ClangdServer::optsForTest();
   Opts.BuildDynamicSymbolIndex = true;
 
-  ClangdServer Server(CDB, FS, DiagConsumer, Opts);
+  ClangdServer Server(CDB, FS, Opts);
 
   FS.Files[testPath("foo.h")] = R"cpp(
     #pragma GCC system_header
 
     // This comment should be retained!
     int foo();
   )cpp";
 

 SignatureHelp signatures(llvm::StringRef Text, Position Point,
                          std::vector<Symbol> IndexSymbols = {}) {
   std::unique_ptr<SymbolIndex> Index;
   if (!IndexSymbols.empty())
     Index = memIndex(IndexSymbols);
 
   MockFSProvider FS;
   MockCompilationDatabase CDB;
-  IgnoreDiagnostics DiagConsumer;
   ClangdServer::Options Opts = ClangdServer::optsForTest();
   Opts.StaticIndex = Index.get();
 
-  ClangdServer Server(CDB, FS, DiagConsumer, Opts);
+  ClangdServer Server(CDB, FS, Opts);
   auto File = testPath("foo.cpp");
   runAddDocument(Server, File, Text);
   return llvm::cantFail(runSignatureHelp(Server, File, Point));
 }
 
 SignatureHelp signatures(llvm::StringRef Text,
                          std::vector<Symbol> IndexSymbols = {}) {
   Annotations Test(Text);
TEST(CompletionTest, DocumentationFromChangedFileCrash) {
   auto FooCpp = testPath("foo.cpp");
   FS.Files[FooH] = R"cpp(
     // this is my documentation comment.
     int func();
   )cpp";
   FS.Files[FooCpp] = "";
 
   MockCompilationDatabase CDB;
-  IgnoreDiagnostics DiagConsumer;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest());
 
   Annotations Source(R"cpp(
     #include "foo.h"
     int func() {
       // This makes sure we have func from header in the AST.
     }
     int a = fun^
   )cpp");

 }
 
 TEST(CompletionTest, NonDocComments) {
   MockFSProvider FS;
   auto FooCpp = testPath("foo.cpp");
   FS.Files[FooCpp] = "";
 
   MockCompilationDatabase CDB;
-  IgnoreDiagnostics DiagConsumer;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest());
 
   Annotations Source(R"cpp(
     // We ignore namespace comments, for rationale see CodeCompletionStrings.h.
     namespace comments_ns {
     }
 
     // ------------------
     int comments_foo();
EXPECT_THAT(
                            AllOf(IsDocumented(), Named("comments_bar")),
                            AllOf(IsDocumented(), Named("comments_qux"))));
 }
 
 TEST(CompletionTest, CompleteOnInvalidLine) {
   auto FooCpp = testPath("foo.cpp");
 
   MockCompilationDatabase CDB;
-  IgnoreDiagnostics DiagConsumer;
   MockFSProvider FS;
   FS.Files[FooCpp] = "// empty file";
 
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest());
   // Run completion outside the file range.
   Position Pos;
   Pos.line = 100;
   Pos.character = 0;
   EXPECT_THAT_EXPECTED(
       runCodeComplete(Server, FooCpp, Pos, clangd::CodeCompleteOptions()),
       Failed());
 }
auto Results = completions(
       )cpp");
 
   EXPECT_THAT(Results.Context, CodeCompletionContext::CCC_DotMemberAccess);
 }
 
 TEST(CompletionTest, FixItForArrowToDot) {
   MockFSProvider FS;
   MockCompilationDatabase CDB;
-  IgnoreDiagnostics DiagConsumer;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest());
 
   CodeCompleteOptions Opts;
   Opts.IncludeFixIts = true;
   Annotations TestCode(
       R"cpp(
         class Auxilary {
          public:
           void AuxFunction();
if (!C.FixIts.empty()) {
       EXPECT_THAT(C.FixIts, ElementsAre(ReplacementEdit));
     }
   }
 }
 
 TEST(CompletionTest, FixItForDotToArrow) {
   MockFSProvider FS;
   MockCompilationDatabase CDB;
-  IgnoreDiagnostics DiagConsumer;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest());
 
   CodeCompleteOptions Opts;
   Opts.IncludeFixIts = true;
   Annotations TestCode(
       R"cpp(
         class Auxilary {
          public:
           void AuxFunction();
TEST(CompletionTest, RenderWithFixItNonMerged) {
   EXPECT_TRUE(R.textEdit);
   EXPECT_EQ(R.textEdit->newText, "Foo::x");
   EXPECT_THAT(R.additionalTextEdits, UnorderedElementsAre(FixIt));
 }
 
 TEST(CompletionTest, CompletionTokenRange) {
   MockFSProvider FS;
   MockCompilationDatabase CDB;
-  IgnoreDiagnostics DiagConsumer;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest());
 
   constexpr const char *TestCodes[] = {
       R"cpp(
         class Auxilary {
          public:
           void AuxFunction();
         };
         void f() {
EXPECT_THAT(
           AllOf(Sig("foo() -> int"), SigDoc("Doc from the index")),
           AllOf(Sig("foo([[int]]) -> int"), SigDoc("Overriden doc from sema")),
           AllOf(Sig("foo([[int]], [[int]]) -> int"), SigDoc("Doc from sema"))));
 }
 
 TEST(SignatureHelpTest, DynamicIndexDocumentation) {
   MockFSProvider FS;
   MockCompilationDatabase CDB;
-  IgnoreDiagnostics DiagConsumer;
   ClangdServer::Options Opts = ClangdServer::optsForTest();
   Opts.BuildDynamicSymbolIndex = true;
-  ClangdServer Server(CDB, FS, DiagConsumer, Opts);
+  ClangdServer Server(CDB, FS, Opts);
 
   FS.Files[testPath("foo.h")] = R"cpp(
     struct Foo {
        // Member doc
        int foo();
     };
   )cpp";
   Annotations FileContent(R"cpp(
for (llvm::StringRef Case : {
     EXPECT_EQ(WantName, Prefix.Name) << Case;
     EXPECT_EQ(WantName.begin(), Prefix.Name.begin()) << Case;
   }
 }
 
 TEST(CompletionTest, EnableSpeculativeIndexRequest) {
   MockFSProvider FS;
   MockCompilationDatabase CDB;
-  IgnoreDiagnostics DiagConsumer;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest());
 
   auto File = testPath("foo.cpp");
   Annotations Test(R"cpp(
       namespace ns1 { int abc; }
       namespace ns2 { int abc; }
       void f() { ns1::ab$1^; ns1::ab$2^; }
       void f2() { ns2::ab$3^; }
   )cpp");

 
 TEST(CompletionTest, NoInsertIncludeIfOnePresent) {
   MockFSProvider FS;
   MockCompilationDatabase CDB;
 
   std::string FooHeader = testPath("foo.h");
   FS.Files[FooHeader] = "";
 
-  IgnoreDiagnostics DiagConsumer;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest());
 
   std::string DeclFile = URI::create(testPath("foo")).toString();
   Symbol Sym = func("Func");
   Sym.CanonicalDeclaration.FileURI = DeclFile.c_str();
   Sym.IncludeHeaders.emplace_back("\"foo.h\"", 2);
   Sym.IncludeHeaders.emplace_back("\"bar.h\"", 1000);
 
   EXPECT_THAT(
EXPECT_THAT(completions("#define Clangd_Macro_Test\nClangd_Macro_T^", {Sym})
               UnorderedElementsAre(Named("Clangd_Macro_Test")));
 }
 
 TEST(CompletionTest, MacroFromPreamble) {
   MockFSProvider FS;
   MockCompilationDatabase CDB;
   std::string FooHeader = testPath("foo.h");
   FS.Files[FooHeader] = "#define CLANGD_PREAMBLE_HEADER x\n";
-  IgnoreDiagnostics DiagConsumer;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest());
   auto Results = completions(
       R"cpp(#include "foo.h"
           #define CLANGD_PREAMBLE_MAIN x
 
           int x = 0;
           #define CLANGD_MAIN x
           void f() { CLANGD_^ }
       )cpp",

 TEST(CompletionTest, IncludedCompletionKinds) {
   MockFSProvider FS;
   MockCompilationDatabase CDB;
   std::string Subdir = testPath("sub");
   std::string SearchDirArg = (Twine("-I") + Subdir).str();
   CDB.ExtraClangFlags = {SearchDirArg.c_str()};
   std::string BarHeader = testPath("sub/bar.h");
   FS.Files[BarHeader] = "";
-  IgnoreDiagnostics DiagConsumer;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest());
   auto Results = completions(Server,
                              R"cpp(
         #include "^"
       )cpp");
   EXPECT_THAT(Results.Completions,
               AllOf(Has("sub/", CompletionItemKind::Folder),
                     Has("bar.h\"", CompletionItemKind::File)));
 }

clang-tools-extra/clangd/unittests/FindSymbolsTests.cpp

 
 using ::testing::AllOf;
 using ::testing::ElementsAre;
 using ::testing::ElementsAreArray;
 using ::testing::Field;
 using ::testing::IsEmpty;
 using ::testing::UnorderedElementsAre;
 
-class IgnoreDiagnostics : public DiagnosticsConsumer {
-  void onDiagnosticsReady(PathRef File,
-                          std::vector<Diag> Diagnostics) override {}
-};
-
 // GMock helpers for matching SymbolInfos items.
 MATCHER_P(QName, Name, "") {
   if (arg.containerName.empty())
     return arg.name == Name;
   return (arg.containerName + "::" + arg.name) == Name;
 }
 MATCHER_P(WithName, N, "") { return arg.name == N; }
 MATCHER_P(WithKind, Kind, "") { return arg.kind == Kind; }
ClangdServer::Options optsForTests() {
   auto ServerOpts = ClangdServer::optsForTest();
   ServerOpts.WorkspaceRoot = testRoot();
   ServerOpts.BuildDynamicSymbolIndex = true;
   return ServerOpts;
 }
 
 class WorkspaceSymbolsTest : public ::testing::Test {
 public:
-  WorkspaceSymbolsTest()
-      : Server(CDB, FSProvider, DiagConsumer, optsForTests()) {
+  WorkspaceSymbolsTest() : Server(CDB, FSProvider, optsForTests()) {
     // Make sure the test root directory is created.
     FSProvider.Files[testPath("unused")] = "";
     CDB.ExtraClangFlags = {"-xc++"};
   }
 
 protected:
   MockFSProvider FSProvider;
   MockCompilationDatabase CDB;
-  IgnoreDiagnostics DiagConsumer;
   ClangdServer Server;
   int Limit = 0;
 
   std::vector<SymbolInformation> getSymbols(llvm::StringRef Query) {
     EXPECT_TRUE(Server.blockUntilIdleForTest()) << "Waiting for preamble";
     auto SymbolInfos = runWorkspaceSymbols(Server, Query, Limit);
     EXPECT_TRUE(bool(SymbolInfos)) << "workspaceSymbols returned an error";
     return *SymbolInfos;
EXPECT_THAT(
           AllOf(QName("Foo<int, T>"), WithKind(SymbolKind::Class)),
           AllOf(QName("Foo<bool, int>"), WithKind(SymbolKind::Class)),
           AllOf(QName("Foo<bool, int, 3>"), WithKind(SymbolKind::Class))));
 }
 
 namespace {
 class DocumentSymbolsTest : public ::testing::Test {
 public:
-  DocumentSymbolsTest()
-      : Server(CDB, FSProvider, DiagConsumer, optsForTests()) {}
+  DocumentSymbolsTest() : Server(CDB, FSProvider, optsForTests()) {}
 
 protected:
   MockFSProvider FSProvider;
   MockCompilationDatabase CDB;
-  IgnoreDiagnostics DiagConsumer;
   ClangdServer Server;
 
   std::vector<DocumentSymbol> getSymbols(PathRef File) {
     EXPECT_TRUE(Server.blockUntilIdleForTest()) << "Waiting for preamble";
     auto SymbolInfos = runDocumentSymbols(Server, File);
     EXPECT_TRUE(bool(SymbolInfos)) << "documentSymbols returned an error";
     return *SymbolInfos;
   }

clang-tools-extra/clangd/unittests/HeaderSourceSwitchTests.cpp

for (const auto &Case : TestCases) {
     auto AST = TU.build();
     EXPECT_EQ(Case.ExpectedResult,
               getCorrespondingHeaderOrSource(testPath(TU.Filename), AST,
                                              Index.get()));
   }
 }
 
 TEST(HeaderSourceSwitchTest, ClangdServerIntegration) {
-  class IgnoreDiagnostics : public DiagnosticsConsumer {
-    void onDiagnosticsReady(PathRef File,
-                            std::vector<Diag> Diagnostics) override {}
-  } DiagConsumer;
   MockCompilationDatabase CDB;
   CDB.ExtraClangFlags = {"-I" +
                          testPath("src/include")}; // add search directory.
   MockFSProvider FS;
   // File heuristic fails here, we rely on the index to find the .h file.
   std::string CppPath = testPath("src/lib/test.cpp");
   std::string HeaderPath = testPath("src/include/test.h");
   FS.Files[HeaderPath] = "void foo();";
   const std::string FileContent = R"cpp(
     #include "test.h"
     void foo() {};
   )cpp";
   FS.Files[CppPath] = FileContent;
   auto Options = ClangdServer::optsForTest();
   Options.BuildDynamicSymbolIndex = true;
-  ClangdServer Server(CDB, FS, DiagConsumer, Options);
+  ClangdServer Server(CDB, FS, Options);
   runAddDocument(Server, CppPath, FileContent);
   EXPECT_EQ(HeaderPath,
             *llvm::cantFail(runSwitchHeaderSource(Server, CppPath)));
 }
 
 } // namespace
 } // namespace clangd
 } // namespace clang

clang-tools-extra/clangd/unittests/RenameTests.cpp

EXPECT_THAT(
       UnorderedElementsAre(
           Pair(Eq(BarPath), Eq(expectedResult(BarCode, NewName))),
           Pair(Eq(MainFilePath), Eq(expectedResult(MainCode, NewName)))));
 }
 
 TEST(CrossFileRenameTests, WithUpToDateIndex) {
   MockCompilationDatabase CDB;
   CDB.ExtraClangFlags = {"-xc++"};
-  class IgnoreDiagnostics : public DiagnosticsConsumer {
-    void onDiagnosticsReady(PathRef File,
-                            std::vector<Diag> Diagnostics) override {}
-  } DiagConsumer;
   // rename is runnning on all "^" points in FooH, and "[[]]" ranges are the
   // expected rename occurrences.
   struct Case {
     llvm::StringRef FooH;
     llvm::StringRef FooCC;
   } Cases[] = {
       {
           // classes.
for (const auto& T : Cases) {
 
     MockFSProvider FS;
     FS.Files[FooHPath] = FooH.code();
     FS.Files[FooCCPath] = FooCC.code();
 
     auto ServerOpts = ClangdServer::optsForTest();
     ServerOpts.CrossFileRename = true;
     ServerOpts.BuildDynamicSymbolIndex = true;
-    ClangdServer Server(CDB, FS, DiagConsumer, ServerOpts);
+    ClangdServer Server(CDB, FS, ServerOpts);
 
     // Add all files to clangd server to make sure the dynamic index has been
     // built.
     runAddDocument(Server, FooHPath, FooH.code());
     runAddDocument(Server, FooCCPath, FooCC.code());
 
     llvm::StringRef NewName = "NewName";
     for (const auto &RenamePos : FooH.points()) {

clang-tools-extra/clangd/unittests/SemanticHighlightingTests.cpp

)cpp",
     #define DXYZ(X) class X {};
     #define DXYZ_Y(Y) DXYZ(x##Y)
     #define DEFINE(X) int X;
     #define DEFINE_Y DEFINE(Y)
   )cpp"}});
 }
 
 TEST(SemanticHighlighting, GeneratesHighlightsWhenFileChange) {
-  class HighlightingsCounterDiagConsumer : public DiagnosticsConsumer {
+  class HighlightingsCounter : public ClangdServer::Callbacks {
   public:
     std::atomic<int> Count = {0};
 
-    void onDiagnosticsReady(PathRef, std::vector<Diag>) override {}
     void onHighlightingsReady(
         PathRef File, std::vector<HighlightingToken> Highlightings) override {
       ++Count;
     }
   };
 
   auto FooCpp = testPath("foo.cpp");
   MockFSProvider FS;
   FS.Files[FooCpp] = "";
 
   MockCompilationDatabase MCD;
-  HighlightingsCounterDiagConsumer DiagConsumer;
-  ClangdServer Server(MCD, FS, DiagConsumer, ClangdServer::optsForTest());
+  HighlightingsCounter Counter;
+  ClangdServer Server(MCD, FS, ClangdServer::optsForTest(), &Counter);
   Server.addDocument(FooCpp, "int a;");
   ASSERT_TRUE(Server.blockUntilIdleForTest()) << "Waiting for server";
-  ASSERT_EQ(DiagConsumer.Count, 1);
+  ASSERT_EQ(Counter.Count, 1);
 }
 
 TEST(SemanticHighlighting, toSemanticHighlightingInformation) {
   auto CreatePosition = [](int Line, int Character) -> Position {
     Position Pos;
     Pos.line = Line;
     Pos.character = Character;
     return Pos;

clang-tools-extra/clangd/unittests/SemanticSelectionTests.cpp

 #include "gmock/gmock.h"
 #include "gtest/gtest.h"
 #include <vector>
 namespace clang {
 namespace clangd {
 namespace {
 using ::testing::ElementsAreArray;
 
-class IgnoreDiagnostics : public DiagnosticsConsumer {
-  void onDiagnosticsReady(PathRef File,
-                          std::vector<Diag> Diagnostics) override {}
-};
-
 TEST(SemanticSelection, All) {
   const char *Tests[] = {
       R"cpp( // Single statement in a function body.
         [[void func() [[{
           [[[[int v = [[1^00]]]];]]
         }]]]]
       )cpp",
       R"cpp( // Expression
for (const char *Test : Tests) {
     EXPECT_THAT(llvm::cantFail(getSemanticRanges(AST, T.point())),
                 ElementsAreArray(T.ranges()))
         << Test;
   }
 }
 
 TEST(SemanticSelection, RunViaClangDServer) {
   MockFSProvider FS;
-  IgnoreDiagnostics DiagConsumer;
   MockCompilationDatabase CDB;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest());
 
   auto FooH = testPath("foo.h");
   FS.Files[FooH] = R"cpp(
     int foo(int x);
     #define HASH(x) ((x) % 10)
   )cpp";
 
   auto FooCpp = testPath("Foo.cpp");

clang-tools-extra/clangd/unittests/TUSchedulerTests.cpp

TEST_F(TUSchedulerTests, Run) {
   S.run("props context", [&] {
     EXPECT_EQ(Context::current().getExisting(TestKey), 10);
     TaskRun.notify();
   });
   TaskRun.wait();
 }
 
 TEST_F(TUSchedulerTests, TUStatus) {
-  class CaptureTUStatus : public DiagnosticsConsumer {
+  class CaptureTUStatus : public ClangdServer::Callbacks {
   public:
     void onDiagnosticsReady(PathRef File,
                             std::vector<Diag> Diagnostics) override {}
 
     void onFileUpdated(PathRef File, const TUStatus &Status) override {
       std::lock_guard<std::mutex> Lock(Mutex);
       AllStatus.push_back(Status);
     }
 
     std::vector<TUStatus> allStatus() {
       std::lock_guard<std::mutex> Lock(Mutex);
       return AllStatus;
     }
 
   private:
     std::mutex Mutex;
     std::vector<TUStatus> AllStatus;
   } CaptureTUStatus;
   MockFSProvider FS;
   MockCompilationDatabase CDB;
-  ClangdServer Server(CDB, FS, CaptureTUStatus, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest(), &CaptureTUStatus);
   Annotations Code("int m^ain () {}");
 
   // We schedule the following tasks in the queue:
   //   [Update] [GoToDefinition]
   Server.addDocument(testPath("foo.cpp"), Code.code(), WantDiagnostics::Yes);
   Server.locateSymbolAt(testPath("foo.cpp"), Code.point(),
                         [](Expected<std::vector<LocatedSymbol>> Result) {
                           ASSERT_TRUE((bool)Result);

clang-tools-extra/clangd/unittests/XRefsTests.cpp

 namespace clangd {
 namespace {
 
 using ::testing::ElementsAre;
 using ::testing::IsEmpty;
 using ::testing::Matcher;
 using ::testing::UnorderedElementsAreArray;
 
-class IgnoreDiagnostics : public DiagnosticsConsumer {
-  void onDiagnosticsReady(PathRef File,
-                          std::vector<Diag> Diagnostics) override {}
-};
-
 MATCHER_P2(FileRange, File, Range, "") {
   return Location{URIForFile::canonicalize(File, testRoot()), Range} == arg;
 }
 
 // Extracts ranges from an annotated example, and constructs a matcher for a
 // highlight set. Ranges should be named $read/$write as appropriate.
 Matcher<const std::vector<DocumentHighlight> &>
 HighlightsFrom(const Annotations &Test) {
)cpp");
 
   // Make the compilation paths appear as ../src/foo.cpp in the compile
   // commands.
   SmallString<32> RelPathPrefix("..");
   llvm::sys::path::append(RelPathPrefix, "src");
   std::string BuildDir = testPath("build");
   MockCompilationDatabase CDB(BuildDir, RelPathPrefix);
 
-  IgnoreDiagnostics DiagConsumer;
   MockFSProvider FS;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest());
 
   // Fill the filesystem.
   auto FooCpp = testPath("src/foo.cpp");
   FS.Files[FooCpp] = "";
   auto HeaderInPreambleH = testPath("src/header_in_preamble.h");
   FS.Files[HeaderInPreambleH] = HeaderInPreambleAnnotations.code();
   auto HeaderNotInPreambleH = testPath("src/header_not_in_preamble.h");
   FS.Files[HeaderNotInPreambleH] = HeaderNotInPreambleAnnotations.code();
)cpp");
   EXPECT_TRUE(bool(Locations)) << "findDefinitions returned an error";
   EXPECT_THAT(*Locations,
               ElementsAre(Sym("bar_not_preamble",
                               HeaderNotInPreambleAnnotations.range())));
 }
 
 TEST(GoToInclude, All) {
   MockFSProvider FS;
-  IgnoreDiagnostics DiagConsumer;
   MockCompilationDatabase CDB;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest());
 
   auto FooCpp = testPath("foo.cpp");
   const char *SourceContents = R"cpp(
   #include ^"$2^foo.h$3^"
   #include "$4^invalid.h"
   int b = a;
   // test
   int foo;
TEST(GoToInclude, All) {
   ASSERT_TRUE(bool(Locations)) << "locateSymbolAt returned an error";
   EXPECT_THAT(*Locations, ElementsAre(Sym("foo.h", HeaderAnnotations.range())));
 }
 
 TEST(LocateSymbol, WithPreamble) {
   // Test stragety: AST should always use the latest preamble instead of last
   // good preamble.
   MockFSProvider FS;
-  IgnoreDiagnostics DiagConsumer;
   MockCompilationDatabase CDB;
-  ClangdServer Server(CDB, FS, DiagConsumer, ClangdServer::optsForTest());
+  ClangdServer Server(CDB, FS, ClangdServer::optsForTest());
 
   auto FooCpp = testPath("foo.cpp");
   // The trigger locations must be the same.
   Annotations FooWithHeader(R"cpp(#include "fo^o.h")cpp");
   Annotations FooWithoutHeader(R"cpp(double    [[fo^o]]();)cpp");
 
   FS.Files[FooCpp] = FooWithHeader.code();