[Completion] Substitute base type for nested types

Ensure we call `getTypeOfMember` for nested nominals and typealiases.
2025-12-14 20:36:38 +01:00 · 2025-02-25 14:49:13 +00:00
parent be0f6f9491
commit 8975bf6c37
4 changed files with 48 additions and 27 deletions
--- a/lib/IDE/CompletionLookup.cpp
+++ b/lib/IDE/CompletionLookup.cpp
@@ -603,7 +603,7 @@ Type CompletionLookup::getTypeOfMember(const ValueDecl *VD,
                                       DynamicLookupInfo dynamicLookupInfo) {
  switch (dynamicLookupInfo.getKind()) {
  case DynamicLookupInfo::None:
-    return getTypeOfMember(VD, this->ExprType);
+    return getTypeOfMember(VD, getMemberBaseType());
  case DynamicLookupInfo::AnyObject:
    return getTypeOfMember(VD, Type());
  case DynamicLookupInfo::KeyPathDynamicMember: {
@@ -676,7 +676,14 @@ Type CompletionLookup::getTypeOfMember(const ValueDecl *VD,
 }

 Type CompletionLookup::getTypeOfMember(const ValueDecl *VD, Type ExprType) {
-  Type T = VD->getInterfaceType();
+  Type T;
+  if (auto *TD = dyn_cast<TypeDecl>(VD)) {
+    // For a type decl we're interested in the declared interface type, i.e
+    // we don't want a metatype.
+    T = TD->getDeclaredInterfaceType();
+  } else {
+    T = VD->getInterfaceType();
+  }
  assert(!T.isNull());

  if (ExprType) {
@@ -1707,13 +1714,16 @@ void CompletionLookup::addNominalTypeRef(const NominalTypeDecl *NTD,
  addLeadingDot(Builder);
  Builder.addBaseName(NTD->getName().str());

+  // Substitute the base type for a nested type if needed.
+  auto nominalTy = getTypeOfMember(NTD, dynamicLookupInfo);
+
  // "Fake" annotation for custom attribute types.
  SmallVector<char, 0> stash;
  StringRef customAttributeAnnotation = getTypeAnnotationString(NTD, stash);
  if (!customAttributeAnnotation.empty()) {
    Builder.addTypeAnnotation(customAttributeAnnotation);
  } else {
-    addTypeAnnotation(Builder, NTD->getDeclaredInterfaceType());
+    addTypeAnnotation(Builder, nominalTy);
  }

  // Override the type relation for NominalTypes. Use the better relation
@@ -1723,8 +1733,7 @@ void CompletionLookup::addNominalTypeRef(const NominalTypeDecl *NTD,
  //   func receiveMetatype(_: Int.Type) {}
  //
  // We want to suggest 'Int' as 'Identical' for both arguments.
-  Builder.setResultTypes(
-      {NTD->getInterfaceType(), NTD->getDeclaredInterfaceType()});
+  Builder.setResultTypes({MetatypeType::get(nominalTy), nominalTy});
  Builder.setTypeContext(expectedTypeContext, CurrDeclContext);
 }

@@ -1737,13 +1746,18 @@ void CompletionLookup::addTypeAliasRef(const TypeAliasDecl *TAD,
  Builder.setAssociatedDecl(TAD);
  addLeadingDot(Builder);
  Builder.addBaseName(TAD->getName().str());
-  if (auto underlyingType = TAD->getUnderlyingType()) {
-    if (underlyingType->hasError()) {
-      addTypeAnnotation(Builder, TAD->getDeclaredInterfaceType());
-    } else {
-      addTypeAnnotation(Builder, underlyingType);
-    }
+
+  // Substitute the base type for a nested typealias if needed.
+  auto ty = getTypeOfMember(TAD, dynamicLookupInfo);
+
+  // If the underlying type has an error, prefer to print the full typealias,
+  // otherwise get the underlying type.
+  if (auto *TA = dyn_cast<TypeAliasType>(ty.getPointer())) {
+    auto underlyingTy = TA->getSinglyDesugaredType();
+    if (!underlyingTy->hasError())
+      ty = underlyingTy;
  }
+  addTypeAnnotation(Builder, ty);
 }

 void CompletionLookup::addGenericTypeParamRef(
--- a/test/IDE/complete_constrained.swift
+++ b/test/IDE/complete_constrained.swift
@@ -75,7 +75,7 @@ func foo(s: MyStruct<Int>) {
 // META_MYSTRUCT_INT_DOT: Begin completions, 11 items
 // META_MYSTRUCT_INT_DOT-DAG: Keyword[self]/CurrNominal:          self[#MyStruct<Int>.Type#]; name=self
 // META_MYSTRUCT_INT_DOT-DAG: Keyword/CurrNominal:                Type[#MyStruct<Int>.Type#]; name=Type
-// META_MYSTRUCT_INT_DOT-DAG: Decl[TypeAlias]/CurrNominal:        Assoc[#T#]; name=Assoc
+// META_MYSTRUCT_INT_DOT-DAG: Decl[TypeAlias]/CurrNominal:        Assoc[#Int#]; name=Assoc
 // META_MYSTRUCT_INT_DOT-DAG: Decl[Constructor]/CurrNominal:      init({#int: U#})[#MyStruct<Int>#]; name=init(int:)
 // META_MYSTRUCT_INT_DOT-DAG: Decl[Constructor]/CurrNominal:      init({#withConstrainedGenericParam: SomeProto#})[#MyStruct<Int>#]; name=init(withConstrainedGenericParam:)
 // META_MYSTRUCT_INT_DOT-DAG: Decl[InstanceMethod]/CurrNominal:   methodWithConstrainedGenericParam({#(self): MyStruct<Int>#})[#(x: SomeProto) -> Int#]; name=methodWithConstrainedGenericParam(:)
--- a/test/IDE/complete_member_type.swift
+++ b/test/IDE/complete_member_type.swift
@@ -90,7 +90,7 @@ do {
  let _: Int!.#^SUGARED_IUOPTIONAL_MEMBER_DOT?check=OPTIONAL^#

  // OPTIONAL-LABEL: Begin completions, 2 items
-  // OPTIONAL-LABEL: Decl[TypeAlias]/CurrNominal: Wrappt[#Wrapped#]; name=Wrappt
+  // OPTIONAL-LABEL: Decl[TypeAlias]/CurrNominal: Wrappt[#Int#]; name=Wrappt
  // OPTIONAL-LABEL: Keyword/None: Type[#{{Optional<Int>|Int\?}}.Type#]; name=Type

  let _: Array<Int>.#^ARRAY_MEMBER_DOT?check=ARRAY^#
@@ -99,10 +99,10 @@ do {
  // ARRAY-LABEL: Begin completions, 8 items
  // ARRAY-DAG: Decl[TypeAlias]/CurrNominal/IsSystem: Index[#Int#]; name=Index
  // ARRAY-DAG: Decl[TypeAlias]/CurrNominal/IsSystem: Indices[#Range<Int>#]; name=Indices
-  // ARRAY-DAG: Decl[TypeAlias]/CurrNominal/IsSystem: Iterator[#IndexingIterator<Array<Element>>#]; name=Iterator
-  // ARRAY-DAG: Decl[TypeAlias]/CurrNominal/IsSystem: Element[#Element#]; name=Element
-  // ARRAY-DAG: Decl[TypeAlias]/CurrNominal/IsSystem: ArrayLiteralElement[#Element#]; name=ArrayLiteralElement
-  // ARRAY-DAG: Decl[TypeAlias]/CurrNominal/IsSystem: SubSequence[#ArraySlice<Element>#]; name=SubSequence
+  // ARRAY-DAG: Decl[TypeAlias]/CurrNominal/IsSystem: Iterator[#IndexingIterator<Array<Int>>#]; name=Iterator
+  // ARRAY-DAG: Decl[TypeAlias]/CurrNominal/IsSystem: Element[#Int#]; name=Element
+  // ARRAY-DAG: Decl[TypeAlias]/CurrNominal/IsSystem: ArrayLiteralElement[#Int#]; name=ArrayLiteralElement
+  // ARRAY-DAG: Decl[TypeAlias]/CurrNominal/IsSystem: SubSequence[#ArraySlice<Int>#]; name=SubSequence
  // ARRAY-DAG: Decl[TypeAlias]/Super/NotRecommended/IsSystem: IndexDistance[#Int#]; name=IndexDistance; diagnostics=warning:'IndexDistance' is deprecated: all index distances are now of type Int
  // ARRAY-DAG: Keyword/None: Type[#{{Array<Int>|\[Int\]}}.Type#]; name=Type

@@ -110,15 +110,15 @@ do {
  let _: [Int : Int].#^SUGARED_DICTIONARY_MEMBER_DOT?check=DICTIONARY^#

  // DICTIONARY-LABEL: Begin completions, 11 items
-  // DICTIONARY-NEXT: Decl[TypeAlias]/CurrNominal/IsSystem: Element[#(key: Key, value: Value)#]; name=Element
-  // DICTIONARY-NEXT: Decl[TypeAlias]/CurrNominal/IsSystem: SubSequence[#Slice<Dictionary<Key, Value>>#]; name=SubSequence
-  // DICTIONARY-NEXT: Decl[TypeAlias]/CurrNominal/IsSystem: Indices[#DefaultIndices<Dictionary<Key, Value>>#]; name=Indices
-  // DICTIONARY-NEXT: Decl[TypeAlias]/CurrNominal/IsSystem: Key[#Key#]; name=Key
-  // DICTIONARY-NEXT: Decl[TypeAlias]/CurrNominal/IsSystem: Value[#Value#]; name=Value
-  // DICTIONARY-NEXT: Decl[Struct]/CurrNominal/IsSystem: Keys[#Dictionary<Key, Value>.Keys#]; name=Keys
-  // DICTIONARY-NEXT: Decl[Struct]/CurrNominal/IsSystem: Values[#Dictionary<Key, Value>.Values#]; name=Values
-  // DICTIONARY-NEXT: Decl[Struct]/CurrNominal/IsSystem: Index[#Dictionary<Key, Value>.Index#]; name=Index
-  // DICTIONARY-NEXT: Decl[Struct]/CurrNominal/IsSystem: Iterator[#Dictionary<Key, Value>.Iterator#]; name=Iterator
+  // DICTIONARY-NEXT: Decl[TypeAlias]/CurrNominal/IsSystem: Element[#(key: Int, value: Int)#]; name=Element
+  // DICTIONARY-NEXT: Decl[TypeAlias]/CurrNominal/IsSystem: SubSequence[#Slice<Dictionary<Int, Int>>#]; name=SubSequence
+  // DICTIONARY-NEXT: Decl[TypeAlias]/CurrNominal/IsSystem: Indices[#DefaultIndices<Dictionary<Int, Int>>#]; name=Indices
+  // DICTIONARY-NEXT: Decl[TypeAlias]/CurrNominal/IsSystem: Key[#Int#]; name=Key
+  // DICTIONARY-NEXT: Decl[TypeAlias]/CurrNominal/IsSystem: Value[#Int#]; name=Value
+  // DICTIONARY-NEXT: Decl[Struct]/CurrNominal/IsSystem: Keys[#Dictionary<Int, Int>.Keys#]; name=Keys
+  // DICTIONARY-NEXT: Decl[Struct]/CurrNominal/IsSystem: Values[#Dictionary<Int, Int>.Values#]; name=Values
+  // DICTIONARY-NEXT: Decl[Struct]/CurrNominal/IsSystem: Index[#Dictionary<Int, Int>.Index#]; name=Index
+  // DICTIONARY-NEXT: Decl[Struct]/CurrNominal/IsSystem: Iterator[#Dictionary<Int, Int>.Iterator#]; name=Iterator
  // DICTIONARY-NEXT: Decl[TypeAlias]/Super/NotRecommended/IsSystem: IndexDistance[#Int#]; name=IndexDistance; diagnostics=warning
  // DICTIONARY-NEXT: Keyword/None: Type[#{{Dictionary<Int, Int>|\[Int : Int\]}}.Type#]; name=Type
 }
@@ -160,3 +160,10 @@ do {
  // MEMBER_EXISTENTIAL_NO_DOT-NEXT: Keyword/None: .Protocol[#(any Sequence).Type#]; name=Protocol
  // MEMBER_EXISTENTIAL_NO_DOT-NEXT: Keyword/None: .Type[#any Sequence.Type#]; name=Type
 }
+
+struct TestGenericTypealias<T, U> {
+  typealias K<V> = TestGenericTypealias<(T, U), V>
+}
+
+let _ = TestGenericTypealias<Int, String>.K<Float>.#^GENERIC_TYPEALIAS^#
+// GENERIC_TYPEALIAS-DAG: Decl[TypeAlias]/CurrNominal: K[#TestGenericTypealias<((Int, String), Float), V>#]; name=K
--- a/test/IDE/complete_name_lookup.swift
+++ b/test/IDE/complete_name_lookup.swift
@@ -49,4 +49,4 @@ extension ObservableConvertibleType {
 // CATCHSEQUENCE_DOT-DAG: Keyword/CurrNominal:                Type[#CatchSequence<_>.Type#]; name=Type
 // CATCHSEQUENCE_DOT-DAG: Decl[Constructor]/CurrNominal/TypeRelation[Convertible]: init()[#CatchSequence<_>#]; name=init()
 // CATCHSEQUENCE_DOT-DAG: Decl[StaticMethod]/Super/TypeRelation[Convertible]: catchError()[#Observable<CatchSequence<_>.T>#]; name=catchError()
-// CATCHSEQUENCE_DOT-DAG: Decl[TypeAlias]/Super:              T[#T#]; name=T
+// CATCHSEQUENCE_DOT-DAG: Decl[TypeAlias]/Super: T[#Observable<_.Element.T>.T#]; name=T