[clang-tools-extra] [clangd] [C++20] [Modules] Introduce initial support for C++20 Modules (PR #66462)

[Chuanqi Xu via cfe-commits]

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@@ -740,6 +741,21 @@ DirectoryBasedGlobalCompilationDatabase::getProjectInfo(PathRef File) const {
   return Res->PI;
 }
 
+std::shared_ptr<ProjectModules>
+DirectoryBasedGlobalCompilationDatabase::getProjectModules(PathRef File) const {
+  CDBLookupRequest Req;
+  Req.FileName = File;
+  Req.ShouldBroadcast = false;
+  Req.FreshTime = Req.FreshTimeMissing =
+      std::chrono::steady_clock::time_point::min();
+  auto Res = lookupCDB(Req);
+  if (!Res)
+    return {};
+  return ProjectModules::create(
+      ProjectModules::ProjectModulesKind::ScanningAllFiles,
+      Res->CDB->getAllFiles(), *this, Opts.TFS);
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ChuanqiXu9 wrote:

I added a FIXME for this since I am not sure can we do here. Should we pass `Res->CDB` here? If we can't solve it in a simple manner. I suggest to address this in future versions and not blocking the initial version.

https://github.com/llvm/llvm-project/pull/66462