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

[Sam McCall via Phabricator via cfe-commits]

sammccall added inline comments.


================
Comment at: clang-tools-extra/clangd/refactor/tweaks/ExtractVariable.cpp:418
+  if (const auto *ME = dyn_cast<MemberExpr>(E))
+    if (const auto *TE = dyn_cast<CXXThisExpr>(ME->getBase()))
+      if (TE->isImplicit())
----------------
dgoldman wrote:
> sammccall wrote:
> > oops, I forgot one detail: we want ME->getBase()->IgnoreImpCasts()
> > 
> > (in `void nonConstMethod() { constMethod(); }` there's an ImplicitCastExpr in there...
> Hmm, is this right, I tested out that example and it seems like that's actually a `CXXMemberCallExpr` which this doesn't handle?
The callee of the CXXMemberCallExpr is the MemberExpr i'm talking about here.


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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()) {
----------------
dgoldman wrote:
> dgoldman wrote:
> > sammccall wrote:
> > > dgoldman wrote:
> > > > 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?
> > > it's similar to the cast you have, but in addition to handling `foo.bar` it handles parens like `(foo.bar)`, commas like `(0, foo.bar)` and casts. All together I think this covers more cases where a pseudo-object can be used as an lvalue and potentially modified.
> > Gotcha, thanks. That makes sense, but it doesn't look like that has any usages and I'm not sure if it's safe to call from this context (e.g. if we can have a non ObjC property PseudoObject expr).  I guess I could modify getObjCProperty to return nullptr in those invalid cases, WDYT?
> @sammccall WDYT about this? Leave as is?
Yeah, that function is not ideal. Leaving as-is sounds fine to me.


Repository:
  rG LLVM Github Monorepo

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

https://reviews.llvm.org/D124486