Don't show deleted function (constructor) candidates for code completion

[yvvan]

Summary

In case of copy constructor is implicitly deleted it's still shown

https://bugs.llvm.org/show_bug.cgi?id=34402 describes a way to reproduce that

[yvvan]

Move the change to the SemaCodeComplete - it should not affect diagnostics

[bkramer]

test/Index/complete-constructor-params.cpp

157 ↗

(On Diff #113741)

This doesn't test anything, FileCheck returns 1 if it doesn't have any input so the test always passes. I'd prefer to rewrite this with CHECK-CC11-NOT instead of negating the FileCheck invocation,

[yvvan]

Fix test

[bkramer]

lgtm

lib/Sema/SemaOverload.cpp

Sema::AddOverloadCandidate(FunctionDecl *Function,
   // C++11 [class.copy]p11: [DR1402]
   //   A defaulted move constructor that is defined as deleted is ignored by
   //   overload resolution.
   CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Function);
   if (Constructor && Constructor->isDefaulted() && Constructor->isDeleted() &&
       Constructor->isMoveConstructor())
     return;
 
+  if (Constructor && Constructor->isCopyConstructor() && Constructor->isDeleted())
+    return;
+
   // Overload resolution is always an unevaluated context.
   EnterExpressionEvaluationContext Unevaluated(
       *this, Sema::ExpressionEvaluationContext::Unevaluated);
 
   // Add this candidate
   OverloadCandidate &Candidate =
       CandidateSet.addCandidate(Args.size(), EarlyConversions);
   Candidate.FoundDecl = FoundDecl;