[Completion] Fix invertible type completion

The previous logic for this was unused, replace
it with new logic that consults
InvertibleProtocols.def for the list of protocols
to suggest.

rdar://139212286

Author: hamishknight

include/swift/IDE/CodeCompletionResult.h

@@ -204,6 +204,7 @@ enum class CompletionKind : uint8_t {
   TypeSimpleBeginning,
   TypeSimpleWithDot,
   TypeSimpleWithoutDot,
+  TypeSimpleInverted,
   CaseStmtKeyword,
   CaseStmtBeginning,
   NominalMemberBeginning,
@@ -231,9 +232,6 @@ enum class CompletionKind : uint8_t {
   TypeAttrBeginning,
   TypeAttrInheritanceBeginning,
   OptionalBinding,
-
-  /// Completion after `~` in an inheritance clause.
-  WithoutConstraintType
 };
 
 enum class CodeCompletionDiagnosticSeverity : uint8_t {

include/swift/IDE/CompletionLookup.h

@@ -593,6 +593,9 @@ class CompletionLookup final : public swift::VisibleDeclConsumer {
 
   void getTypeCompletions(Type BaseType);
 
+  /// Add completions for types that can appear after a \c ~ prefix.
+  void getInvertedTypeCompletions();
+
   void getGenericRequirementCompletions(DeclContext *DC,
                                         SourceLoc CodeCompletionLoc);
 
@@ -631,8 +634,6 @@ class CompletionLookup final : public swift::VisibleDeclConsumer {
   void getStmtLabelCompletions(SourceLoc Loc, bool isContinue);
 
   void getOptionalBindingCompletions(SourceLoc Loc);
-
-  void addWithoutConstraintTypes();
 };
 
 } // end namespace ide

include/swift/Parse/IDEInspectionCallbacks.h

@@ -204,6 +204,9 @@ class CodeCompletionCallbacks {
   /// Complete a given \c type-simple when there is no trailing dot.
   virtual void completeTypeSimpleWithoutDot(TypeRepr *TR){};
 
+  /// Complete a given \c type-simple following a \c ~ prefix.
+  virtual void completeTypeSimpleInverted() {};
+
   /// Complete the beginning of a case statement at the top of switch stmt.
   virtual void completeCaseStmtKeyword() {};
 
@@ -291,8 +294,6 @@ class CodeCompletionCallbacks {
   virtual void completeTypeAttrInheritanceBeginning() {};
 
   virtual void completeOptionalBinding(){};
-
-  virtual void completeWithoutConstraintType(){};
 };
 
 class DoneParsingCallback {

lib/IDE/CodeCompletion.cpp

@@ -267,6 +267,7 @@ class CodeCompletionCallbacksImpl : public CodeCompletionCallbacks,
   void completeTypeSimpleBeginning() override;
   void completeTypeSimpleWithDot(TypeRepr *TR) override;
   void completeTypeSimpleWithoutDot(TypeRepr *TR) override;
+  void completeTypeSimpleInverted() override;
 
   void completeCaseStmtKeyword() override;
   void completeCaseStmtBeginning(CodeCompletionExpr *E) override;
@@ -305,7 +306,6 @@ class CodeCompletionCallbacksImpl : public CodeCompletionCallbacks,
   void completeTypeAttrBeginning() override;
   void completeTypeAttrInheritanceBeginning() override;
   void completeOptionalBinding() override;
-  void completeWithoutConstraintType() override;
 
   void doneParsing(SourceFile *SrcFile) override;
 
@@ -509,6 +509,11 @@ void CodeCompletionCallbacksImpl::completeTypeSimpleWithoutDot(TypeRepr *TR) {
   CurDeclContext = P.CurDeclContext;
 }
 
+void CodeCompletionCallbacksImpl::completeTypeSimpleInverted() {
+  Kind = CompletionKind::TypeSimpleInverted;
+  CurDeclContext = P.CurDeclContext;
+}
+
 void CodeCompletionCallbacksImpl::completeCaseStmtKeyword() {
   Kind = CompletionKind::CaseStmtKeyword;
   CurDeclContext = P.CurDeclContext;
@@ -646,11 +651,6 @@ void CodeCompletionCallbacksImpl::completeOptionalBinding() {
   Kind = CompletionKind::OptionalBinding;
 }
 
-void CodeCompletionCallbacksImpl::completeWithoutConstraintType() {
-  CurDeclContext = P.CurDeclContext;
-  Kind = CompletionKind::WithoutConstraintType;
-}
-
 void CodeCompletionCallbacksImpl::completeTypeAttrBeginning() {
   CurDeclContext = P.CurDeclContext;
   Kind = CompletionKind::TypeAttrBeginning;
@@ -993,7 +993,6 @@ void CodeCompletionCallbacksImpl::addKeywords(CodeCompletionResultSink &Sink,
   case CompletionKind::TypeAttrBeginning:
   case CompletionKind::TypeAttrInheritanceBeginning:
   case CompletionKind::OptionalBinding:
-  case CompletionKind::WithoutConstraintType:
     break;
 
   case CompletionKind::EffectsSpecifier:
@@ -1066,6 +1065,7 @@ void CodeCompletionCallbacksImpl::addKeywords(CodeCompletionResultSink &Sink,
     break;
   case CompletionKind::CaseStmtBeginning:
   case CompletionKind::TypeSimpleWithDot:
+  case CompletionKind::TypeSimpleInverted:
     break;
 
   case CompletionKind::TypeSimpleWithoutDot:
@@ -1296,9 +1296,9 @@ void swift::ide::postProcessCompletionResults(
         Kind != CompletionKind::TypeSimpleBeginning &&
         Kind != CompletionKind::TypeSimpleWithoutDot &&
         Kind != CompletionKind::TypeSimpleWithDot &&
+        Kind != CompletionKind::TypeSimpleInverted &&
         Kind != CompletionKind::TypeDeclResultBeginning &&
-        Kind != CompletionKind::GenericRequirement &&
-        Kind != CompletionKind::WithoutConstraintType) {
+        Kind != CompletionKind::GenericRequirement) {
       flair |= CodeCompletionFlairBit::RareTypeAtCurrentPosition;
       modified = true;
     }
@@ -1807,6 +1807,11 @@ void CodeCompletionCallbacksImpl::doneParsing(SourceFile *SrcFile) {
     break;
   }
 
+  case CompletionKind::TypeSimpleInverted: {
+    Lookup.getInvertedTypeCompletions();
+    break;
+  }
+
   case CompletionKind::NominalMemberBeginning: {
     CompletionOverrideLookup OverrideLookup(CompletionContext.getResultSink(),
                                             P.Context, CurDeclContext,
@@ -1955,11 +1960,6 @@ void CodeCompletionCallbacksImpl::doneParsing(SourceFile *SrcFile) {
     break;
   }
 
-  case CompletionKind::WithoutConstraintType: {
-    Lookup.addWithoutConstraintTypes();
-    break;
-  }
-
   case CompletionKind::AfterIfStmtElse:
   case CompletionKind::CaseStmtKeyword:
   case CompletionKind::EffectsSpecifier:

lib/IDE/CompletionLookup.cpp

@@ -2964,6 +2964,22 @@ void CompletionLookup::getTypeCompletions(Type BaseType) {
   }
 }
 
+void CompletionLookup::getInvertedTypeCompletions() {
+  Kind = LookupKind::Type;
+
+  auto addCompletion = [&](InvertibleProtocolKind invertableKind) {
+    auto *P = Ctx.getProtocol(getKnownProtocolKind(invertableKind));
+    if (!P)
+      return;
+
+    addNominalTypeRef(P, DeclVisibilityKind::VisibleAtTopLevel,
+                      DynamicLookupInfo());
+  };
+#define INVERTIBLE_PROTOCOL(Name, Bit)         \
+  addCompletion(InvertibleProtocolKind::Name);
+#include "swift/ABI/InvertibleProtocols.def"
+}
+
 void CompletionLookup::getGenericRequirementCompletions(
     DeclContext *DC, SourceLoc CodeCompletionLoc) {
   auto genericSig = DC->getGenericSignatureOfContext();
@@ -3490,9 +3506,3 @@ void CompletionLookup::getOptionalBindingCompletions(SourceLoc Loc) {
   lookupVisibleDecls(FilteringConsumer, Loc, CurrDeclContext,
                      /*IncludeTopLevel=*/false);
 }
-
-void CompletionLookup::addWithoutConstraintTypes() {
-  auto *CopyableDecl = Ctx.getProtocol(KnownProtocolKind::Copyable);
-  addNominalTypeRef(CopyableDecl, DeclVisibilityKind::VisibleAtTopLevel,
-                    DynamicLookupInfo());
-}

lib/Parse/ParseType.cpp

@@ -227,7 +227,11 @@ ParserResult<TypeRepr> Parser::parseTypeSimple(
     break;
   case tok::code_complete:
     if (CodeCompletionCallbacks) {
-      CodeCompletionCallbacks->completeTypeSimpleBeginning();
+      if (tildeLoc.isValid()) {
+        CodeCompletionCallbacks->completeTypeSimpleInverted();
+      } else {
+        CodeCompletionCallbacks->completeTypeSimpleBeginning();
+      }
     }
     return makeParserCodeCompletionResult<TypeRepr>(
         ErrorTypeRepr::create(Context, consumeToken(tok::code_complete)));

test/IDE/complete_without_constraint_type.swift

@@ -1,4 +1,7 @@
 // RUN: %batch-code-completion
 
+// rdar://139212286 - We should only suggest invertible types here.
 struct FileDescriptor: ~#^COMPLETE^# {}
-// COMPLETE: Decl[Protocol]/OtherModule[Swift]/IsSystem: Copyable[#Copyable#]; name=Copyable
+// COMPLETE:     Begin completions, 2 items
+// COMPLETE-DAG: Decl[Protocol]/OtherModule[Swift]/IsSystem: Copyable[#Copyable#]; name=Copyable
+// COMPLETE-DAG: Decl[Protocol]/OtherModule[Swift]/IsSystem: Escapable[#Escapable#]; name=Escapable