[clang-tools-extra] [clangd] Let DefineOutline tweak handle member function templates (PR #112345)

[Nathan Ridge via cfe-commits]

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@@ -130,23 +129,40 @@ getFunctionSourceAfterReplacements(const FunctionDecl *FD,
     return QualifiedFunc.takeError();
 
   std::string TemplatePrefix;
+  auto AddToTemplatePrefixIfApplicable = [&](const Decl *D, bool append) {
+    const TemplateParameterList *Params = D->getDescribedTemplateParams();
+    if (!Params)
+      return;
+    for (Decl *P : *Params) {
+      if (auto *TTP = dyn_cast<TemplateTypeParmDecl>(P))
+        TTP->removeDefaultArgument();
+      else if (auto *NTTP = dyn_cast<NonTypeTemplateParmDecl>(P))
+        NTTP->removeDefaultArgument();
+      else if (auto *TTPD = dyn_cast<TemplateTemplateParmDecl>(P))
+        TTPD->removeDefaultArgument();
+    }
+    std::string S;
+    llvm::raw_string_ostream Stream(S);
+    Params->print(Stream, FD->getASTContext());
+    if (!S.empty())
+      *S.rbegin() = '\n'; // Replace space with newline
+    if (append)
+      TemplatePrefix.append(S);
+    else
+      TemplatePrefix.insert(0, S);
+  };
   if (auto *MD = llvm::dyn_cast<CXXMethodDecl>(FD)) {
     for (const CXXRecordDecl *Parent = MD->getParent(); Parent;
          Parent =
              llvm::dyn_cast_or_null<const CXXRecordDecl>(Parent->getParent())) {
-      if (const TemplateParameterList *Params =
-              Parent->getDescribedTemplateParams()) {
-        std::string S;
-        llvm::raw_string_ostream Stream(S);
-        Params->print(Stream, FD->getASTContext());
-        if (!S.empty())
-          *S.rbegin() = '\n'; // Replace space with newline
-        TemplatePrefix.insert(0, S);
-      }
+      AddToTemplatePrefixIfApplicable(Parent, false);
     }
   }
 
+  AddToTemplatePrefixIfApplicable(FD, true);
   auto Source = QualifiedFunc->substr(FuncBegin, FuncEnd - FuncBegin + 1);
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HighCommander4 wrote:

This is really a comment on the pre-existing code, but could you move this declaration of `Source` further up, to before `TemplatePrefix`?

https://github.com/llvm/llvm-project/pull/112345