[clang-tools-extra] [clangd] Support .clangd command line modifications for C++ modules (PR #122606)

[kadir çetinkaya via cfe-commits]

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@@ -36,11 +38,16 @@ namespace clangd {
 /// `<primary-module-name>[:partition-name]`. So module names covers partitions.
 class ProjectModules {
 public:
+  using CommandProvider =
+      llvm::unique_function<void(tooling::CompileCommand &, PathRef) const>;
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kadircet wrote:

this looks like a command-mangler, rather than command-provider to me

https://github.com/llvm/llvm-project/pull/122606