[PATCH] D124486: [clangd] ExtractVariable support for C and Objective-C

[David Goldman via Phabricator via cfe-commits]

dgoldman added inline comments.


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Comment at: clang-tools-extra/clangd/refactor/tweaks/ExtractVariable.cpp:170
+  if (E->hasPlaceholderType(BuiltinType::PseudoObject)) {
+    if (const auto *PR = dyn_cast<ObjCPropertyRefExpr>(E)) {
+      if (PR->isMessagingSetter()) {
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sammccall wrote:
> E->getObjCProperty()?
Hmm I'm not sure when that would be useful looking at the logic there, can you give an example just to make sure I understand what it would handle?


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Comment at: clang-tools-extra/clangd/refactor/tweaks/ExtractVariable.cpp:176
+        // it returns nil (setter method must have a void return type).
+        return "";
+      } else if (PR->isMessagingGetter()) {
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sammccall wrote:
> please don't use "" as a sentinel value, it will lead to bugs
> 
> Why are we checking this here rather than in eligibleForExtraction?
I put it in the ExtractionContext constructor since we would otherwise have to perform the same logic twice to compute the type string. I could make it into a function to be shared by both if you'd like? 


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Comment at: clang-tools-extra/clangd/refactor/tweaks/ExtractVariable.cpp:208
+  std::string ExtractedVarDecl =
+      Type + " " + VarName.str() + " = " + ExtractionCode.str() + "; ";
   return tooling::Replacement(SM, InsertionLoc, 0, ExtractedVarDecl);
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sammccall wrote:
> Type + Varname isn't correct for types in general, particularly those that use declarator syntax.
> printType with varname as the placeholder should do what you want.
> 
> Can you add a testcase where the variable has function pointer type?
I went ahead and added this but I couldn't think of a way to get a result like this without enabling this for MemberExprs, so I went ahead and re-enabled for them since I think it could be useful for them. LMK if I should revert that change. I guess if we don't want to support MemberExprs I should disable the ObjC property support since it probably makes to match the C++ equivalent?


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  https://reviews.llvm.org/D124486/new/

https://reviews.llvm.org/D124486