Sema: Remove hack introduced by 31245556

It looks like Type::subst() was subsequently fixed for GenericFunctionTypes
in 06d1679 so we can remove this hack.

Author: slavapestov

lib/AST/LookupVisibleDecls.cpp

@@ -768,17 +768,6 @@ template <> struct DenseMapInfo<FoundDeclTy> {
 
 namespace {
 
-/// Hack to guess at whether substituting into the type of a declaration will
-/// be okay.
-/// FIXME: This is awful. We should either have Type::subst() work for
-/// GenericFunctionType, or we should kill it outright.
-static bool shouldSubstIntoDeclType(Type type) {
-  auto genericFnType = type->getAs<GenericFunctionType>();
-  if (!genericFnType) return true;
-
-  return false;
-}
-
 class OverrideFilteringConsumer : public VisibleDeclConsumer {
 public:
   std::set<ValueDecl *> AllFoundDecls;
@@ -870,8 +859,7 @@ class OverrideFilteringConsumer : public VisibleDeclConsumer {
 
     auto FoundSignature = VD->getOverloadSignature();
     auto FoundSignatureType = VD->getOverloadSignatureType();
-    if (FoundSignatureType && shouldSubst &&
-        shouldSubstIntoDeclType(FoundSignatureType)) {
+    if (FoundSignatureType && shouldSubst) {
       auto subs = BaseTy->getMemberSubstitutionMap(M, VD);
       if (auto CT = FoundSignatureType.subst(subs))
         FoundSignatureType = CT->getCanonicalType();
@@ -888,8 +876,7 @@ class OverrideFilteringConsumer : public VisibleDeclConsumer {
 
       auto OtherSignature = OtherVD->getOverloadSignature();
       auto OtherSignatureType = OtherVD->getOverloadSignatureType();
-      if (OtherSignatureType && shouldSubst &&
-          shouldSubstIntoDeclType(OtherSignatureType)) {
+      if (OtherSignatureType && shouldSubst) {
         auto subs = BaseTy->getMemberSubstitutionMap(M, OtherVD);
         if (auto CT = OtherSignatureType.subst(subs))
           OtherSignatureType = CT->getCanonicalType();

test/IDE/complete_from_stdlib.swift

@@ -148,7 +148,7 @@ func testArchetypeReplacement2<BAR : Equatable>(_ a: [BAR]) {
 // PRIVATE_NOMINAL_MEMBERS_6-DAG: Decl[InstanceMethod]/CurrNominal:   append({#(newElement): Equatable#})[#Void#]{{; name=.+}}
 // PRIVATE_NOMINAL_MEMBERS_6-DAG: Decl[InstanceMethod]/CurrNominal:   insert({#(newElement): Equatable#}, {#at: Int#})[#Void#]{{; name=.+}}
 // PRIVATE_NOMINAL_MEMBERS_6-DAG: Decl[InstanceMethod]/Super:         dropFirst()[#ArraySlice<Equatable>#]{{; name=.+}}
-// PRIVATE_NOMINAL_MEMBERS_6-DAG: Decl[InstanceMethod]/Super:         dropLast()[#ArraySlice<Equatable>#]{{; name=.+}}
+// PRIVATE_NOMINAL_MEMBERS_6-DAG: Decl[InstanceMethod]/Super:         dropLast()[#[Equatable]#]{{; name=.+}}
 // PRIVATE_NOMINAL_MEMBERS_6-DAG: Decl[InstanceMethod]/Super:         enumerated()[#EnumeratedSequence<[Equatable]>#]{{; name=.+}}
 // PRIVATE_NOMINAL_MEMBERS_6-DAG: Decl[InstanceMethod]/Super:         min({#by: (Equatable, Equatable) throws -> Bool##(Equatable, Equatable) throws -> Bool#})[' rethrows'][#Equatable?#]{{; name=.+}}
 // PRIVATE_NOMINAL_MEMBERS_6-DAG: Decl[InstanceMethod]/Super:         max({#by: (Equatable, Equatable) throws -> Bool##(Equatable, Equatable) throws -> Bool#})[' rethrows'][#Equatable?#]{{; name=.+}}

test/IDE/complete_value_expr.swift

@@ -1850,10 +1850,13 @@ struct dedupS : dedupP {
 func testDeDuped(_ x: dedupS) {
   x#^PROTOCOL_EXT_DEDUP_1^#
 // FIXME: Should produce 3 items (?)
-// PROTOCOL_EXT_DEDUP_1: Begin completions, 7 items
+
+// PROTOCOL_EXT_DEDUP_1: Begin completions, 6 items
 // PROTOCOL_EXT_DEDUP_1: Decl[InstanceMethod]/CurrNominal:   .foo()[#Int#]; name=foo()
 // PROTOCOL_EXT_DEDUP_1: Decl[InstanceVar]/CurrNominal:      .bar[#Int#]; name=bar
 // PROTOCOL_EXT_DEDUP_1: Decl[Subscript]/CurrNominal:        [{#Int#}][#Int#]; name=[Int]
+// PROTOCOL_EXT_DEDUP_1: Decl[InstanceVar]/Super:            .bar[#Int#]; name=bar
+// PROTOCOL_EXT_DEDUP_1: Decl[Subscript]/Super:              [{#Self.T#}][#Self.T#]; name=[Self.T]
 // PROTOCOL_EXT_DEDUP_1: Keyword[self]/CurrNominal:          .self[#dedupS#]; name=self
 // PROTOCOL_EXT_DEDUP_1: End completions
 }