[clang-tools-extra] [clangd] [Modules] Support Reusable Modules Builder (PR #106683)

[kadir çetinkaya via cfe-commits]

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@@ -85,19 +85,20 @@ class PrerequisiteModules {
 /// different versions and different source files.
 class ModulesBuilder {
 public:
-  ModulesBuilder(const GlobalCompilationDatabase &CDB) : CDB(CDB) {}
+  ModulesBuilder() = default;
+  virtual ~ModulesBuilder() = default;
 
   ModulesBuilder(const ModulesBuilder &) = delete;
   ModulesBuilder(ModulesBuilder &&) = delete;
 
   ModulesBuilder &operator=(const ModulesBuilder &) = delete;
   ModulesBuilder &operator=(ModulesBuilder &&) = delete;
 
-  std::unique_ptr<PrerequisiteModules>
-  buildPrerequisiteModulesFor(PathRef File, const ThreadsafeFS &TFS) const;
+  virtual std::unique_ptr<PrerequisiteModules>
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kadircet wrote:

not sure why we need to make this an abstract base class, instead of concretely implementing the functionality here.

we're only using the caching version of `ModulesBuilder` in actual code & tests anyway.

https://github.com/llvm/llvm-project/pull/106683