From 16987998e6a0ad62efd4e387c18b0b9b5ef51947 Mon Sep 17 00:00:00 2001
From: Haojian Wu <hokein.wu@gmail.com>
Date: Mon, 5 Sep 2022 14:55:13 +0200
Subject: [PATCH] [clangd] Fix LineFoldingOnly flag is not propagated correctly
 to ClangdServer.

The Opts.LineFoldingOnly must be set before the clangdServer
construction, otherwise this flag is always false when using clangd in VSCode.

Differential Revision: https://reviews.llvm.org/D133299
---
 clang-tools-extra/clangd/ClangdLSPServer.cpp  | 53 ++++++++++---------
 .../clangd/test/folding-range.test            | 24 +++++++++
 2 files changed, 51 insertions(+), 26 deletions(-)
 create mode 100644 clang-tools-extra/clangd/test/folding-range.test

diff --git a/clang-tools-extra/clangd/ClangdLSPServer.cpp b/clang-tools-extra/clangd/ClangdLSPServer.cpp
index 449ac9e3a85b..c5238e426d69 100644
--- a/clang-tools-extra/clangd/ClangdLSPServer.cpp
+++ b/clang-tools-extra/clangd/ClangdLSPServer.cpp
@@ -466,32 +466,6 @@ void ClangdLSPServer::onInitialize(const InitializeParams &Params,
   if (Server)
     return Reply(llvm::make_error<LSPError>("server already initialized",
                                             ErrorCode::InvalidRequest));
-  if (Opts.UseDirBasedCDB) {
-    DirectoryBasedGlobalCompilationDatabase::Options CDBOpts(TFS);
-    if (const auto &Dir = Params.initializationOptions.compilationDatabasePath)
-      CDBOpts.CompileCommandsDir = Dir;
-    CDBOpts.ContextProvider = Opts.ContextProvider;
-    BaseCDB =
-        std::make_unique<DirectoryBasedGlobalCompilationDatabase>(CDBOpts);
-    BaseCDB = getQueryDriverDatabase(llvm::makeArrayRef(Opts.QueryDriverGlobs),
-                                     std::move(BaseCDB));
-  }
-  auto Mangler = CommandMangler::detect();
-  if (Opts.ResourceDir)
-    Mangler.ResourceDir = *Opts.ResourceDir;
-  CDB.emplace(BaseCDB.get(), Params.initializationOptions.fallbackFlags,
-              tooling::ArgumentsAdjuster(std::move(Mangler)));
-  {
-    // 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 (Opts.Encoding)
-      WithOffsetEncoding.emplace(kCurrentOffsetEncoding, *Opts.Encoding);
-    Server.emplace(*CDB, TFS, Opts,
-                   static_cast<ClangdServer::Callbacks *>(this));
-  }
 
   Opts.CodeComplete.EnableSnippets = Params.capabilities.CompletionSnippets;
   Opts.CodeComplete.IncludeFixIts = Params.capabilities.CompletionFixes;
@@ -521,6 +495,33 @@ void ClangdLSPServer::onInitialize(const InitializeParams &Params,
   BackgroundIndexSkipCreate = Params.capabilities.ImplicitProgressCreation;
   Opts.ImplicitCancellation = !Params.capabilities.CancelsStaleRequests;
 
+  if (Opts.UseDirBasedCDB) {
+    DirectoryBasedGlobalCompilationDatabase::Options CDBOpts(TFS);
+    if (const auto &Dir = Params.initializationOptions.compilationDatabasePath)
+      CDBOpts.CompileCommandsDir = Dir;
+    CDBOpts.ContextProvider = Opts.ContextProvider;
+    BaseCDB =
+        std::make_unique<DirectoryBasedGlobalCompilationDatabase>(CDBOpts);
+    BaseCDB = getQueryDriverDatabase(llvm::makeArrayRef(Opts.QueryDriverGlobs),
+                                     std::move(BaseCDB));
+  }
+  auto Mangler = CommandMangler::detect();
+  if (Opts.ResourceDir)
+    Mangler.ResourceDir = *Opts.ResourceDir;
+  CDB.emplace(BaseCDB.get(), Params.initializationOptions.fallbackFlags,
+              tooling::ArgumentsAdjuster(std::move(Mangler)));
+  {
+    // 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 (Opts.Encoding)
+      WithOffsetEncoding.emplace(kCurrentOffsetEncoding, *Opts.Encoding);
+    Server.emplace(*CDB, TFS, Opts,
+                   static_cast<ClangdServer::Callbacks *>(this));
+  }
+
   llvm::json::Object ServerCaps{
       {"textDocumentSync",
        llvm::json::Object{
diff --git a/clang-tools-extra/clangd/test/folding-range.test b/clang-tools-extra/clangd/test/folding-range.test
new file mode 100644
index 000000000000..758980d2061d
--- /dev/null
+++ b/clang-tools-extra/clangd/test/folding-range.test
@@ -0,0 +1,24 @@
+# RUN: clangd -lit-test < %s | FileCheck -strict-whitespace %s
+void f() {
+
+}
+---
+{"jsonrpc":"2.0","id":0,"method":"initialize","params":{"processId":123,"rootPath":"clangd","capabilities":{"textDocument": {"foldingRange": {"lineFoldingOnly": true}}},"trace":"off"}}
+---
+{"jsonrpc":"2.0","method":"textDocument/didOpen","params":{"textDocument":{"languageId":"cpp","text":"void f() {\n\n}\n","uri":"test:///foo.cpp","version":1}}}
+---
+{"id":1,"jsonrpc":"2.0","method":"textDocument/foldingRange","params":{"textDocument":{"uri":"test:///foo.cpp"}}}
+# CHECK:      "id": 1,
+# CHECK-NEXT: "jsonrpc": "2.0",
+# CHECK-NEXT: "result": [
+# CHECK-NEXT:   {
+# CHECK-NEXT:     "endLine": 1,
+# CHECK-NEXT:     "kind": "region", 
+# CHECK-NEXT:     "startCharacter": 10,
+# CHECK-NEXT:     "startLine": 0
+# CHECK-NEXT:   }
+# CHECK-NEXT: ]
+---
+{"jsonrpc":"2.0","id":5,"method":"shutdown"}
+---
+{"jsonrpc":"2.0","method":"exit"}