[clang-tools-extra] [clangd] Retrieve documentation for member function instance from index (PR #153337)

[Nathan Ridge via cfe-commits]

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@@ -1887,7 +1887,19 @@ class CodeCompleteFlow {
         for (auto &Cand : C.first) {
           if (Cand.SemaResult &&
               Cand.SemaResult->Kind == CodeCompletionResult::RK_Declaration) {
-            auto ID = clangd::getSymbolID(Cand.SemaResult->getDeclaration());
+            const NamedDecl *DeclToLookup = Cand.SemaResult->getDeclaration();
+            // For instantiations of members of class templates, the
+            // documentation will be stored at the member's original
+            // declaration.
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HighCommander4 wrote:

> do we know why the discrepancy exists between templated-code itself vs non-templated decls (i.e. how come we get the decl with comments when we're looking at `foo<int>()`)?

I'm not sure I'm following. Is `foo` is a function template here? In what context are you requesting completion?

https://github.com/llvm/llvm-project/pull/153337