[clang-tools-extra] [clang-tidy] filter check options by enabled checks in '--dump-config' (PR #147142)

[Victor Chernyakin via cfe-commits]

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@@ -503,6 +503,21 @@ getCheckNames(const ClangTidyOptions &Options,
   return Factory.getCheckNames();
 }
 
+void filterCheckOptions(ClangTidyOptions &Options,
+                        const std::vector<std::string> &EnabledChecks) {
+  StringSet<> EnabledChecksSet(llvm::from_range, EnabledChecks);
+  ClangTidyOptions::OptionMap FilteredOptions;
+  for (const auto &[OptionName, Value] : Options.CheckOptions) {
+    const size_t CheckNameEndPos = OptionName.find('.');
+    if (CheckNameEndPos == StringRef::npos)
+      continue;
+    const StringRef CheckName = OptionName.substr(0, CheckNameEndPos);
+    if (EnabledChecksSet.contains(CheckName))
+      FilteredOptions[OptionName] = Value;
+  }
+  Options.CheckOptions = std::move(FilteredOptions);
+}
----------------
localspook wrote:

`StringMap::erase` returns `void`, which I *think* means it doesn't invalidate iterators, but I agree, involving iterators at all makes it less readable. If `StringMap` was compatible with `llvm::erase_if`, we could get the best of both worlds, but it doesn't seem to be right now...

https://github.com/llvm/llvm-project/pull/147142