[clang-tools-extra] [clangd] Make clangd-indexer respect .clangd configuration files (PR #214951)

[via cfe-commits]

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@@ -152,6 +166,20 @@ int main(int argc, const char **argv) {
     return 1;
   }
 
+  clang::clangd::RealThreadsafeFS TFS;
+  std::vector<std::unique_ptr<clang::clangd::config::Provider>> ProviderStack;
+  if (clang::clangd::EnableConfig)
+    ProviderStack =
+        clang::clangd::config::Provider::createDefaultProviders(TFS);
+  std::vector<const clang::clangd::config::Provider *> ProviderPointers;
+  for (const auto &P : ProviderStack)
+    ProviderPointers.push_back(P.get());
+  auto ConfigProvider =
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JVApen wrote:

I'm not sure if this is a good suggestion, though I wonder if lines 170-178 should be in a separate function in provider. (Returning a struct/pair to guarantee ownership) I'm pretty sure this is a copy from the clangd main. I wouldn't include 179-180 as that requires ClangdServer. 

https://github.com/llvm/llvm-project/pull/214951