Merge pull request #73042 from ahoppen/6.0/parameter-pack-pattern-crash

[CodeCompletion] Fix a crash when completing the call pattern of a function that takes a parameter pack

Author: rintaro

include/swift/Sema/ConstraintSystem.h

@@ -908,7 +908,7 @@ class FunctionArgApplyInfo {
                         bool lookThroughAutoclosure) const {
     auto param = fnTy->getParams()[ParamIdx];
     auto paramTy = param.getPlainType();
-    if (lookThroughAutoclosure && param.isAutoClosure())
+    if (lookThroughAutoclosure && param.isAutoClosure() && paramTy->is<FunctionType>())
       paramTy = paramTy->castTo<FunctionType>()->getResult();
     return paramTy;
   }

lib/IDE/ArgumentCompletion.cpp

@@ -89,43 +89,6 @@ bool ArgumentTypeCheckCompletionCallback::addPossibleParams(
   return ShowGlobalCompletions;
 }
 
-/// Applies heuristic to determine whether the result type of \p E is
-/// unconstrained, that is if the constraint system is satisfiable for any
-/// result type of \p E.
-static bool isExpressionResultTypeUnconstrained(const Solution &S, Expr *E) {
-  ConstraintSystem &CS = S.getConstraintSystem();
-  if (auto ParentExpr = CS.getParentExpr(E)) {
-    if (auto Assign = dyn_cast<AssignExpr>(ParentExpr)) {
-      if (isa<DiscardAssignmentExpr>(Assign->getDest())) {
-        // _ = <expr> is unconstrained
-        return true;
-      }
-    } else if (isa<RebindSelfInConstructorExpr>(ParentExpr)) {
-      // super.init() is unconstrained (it always produces the correct result
-      // by definition)
-      return true;
-    }
-  }
-  auto target = S.getTargetFor(E);
-  if (!target)
-    return false;
-
-  assert(target->kind == SyntacticElementTarget::Kind::expression);
-  switch (target->getExprContextualTypePurpose()) {
-  case CTP_Unused:
-    // If we aren't using the contextual type, its unconstrained by definition.
-    return true;
-  case CTP_Initialization: {
-    // let x = <expr> is unconstrained
-    auto contextualType = target->getExprContextualType();
-    return !contextualType || contextualType->is<UnresolvedType>();
-  }
-  default:
-    // Assume that it's constrained by default.
-    return false;
-  }
-}
-
 /// Returns whether `E` has a parent expression with arguments.
 static bool hasParentCallLikeExpr(Expr *E, ConstraintSystem &CS) {
   E = CS.getParentExpr(E);
@@ -172,10 +135,21 @@ void ArgumentTypeCheckCompletionCallback::sawSolutionImpl(const Solution &S) {
   auto ArgIdx = ArgInfo->completionIdx;
 
   Type ExpectedCallType;
-  if (!isExpressionResultTypeUnconstrained(S, ParentCall)) {
-    ExpectedCallType = getTypeForCompletion(S, ParentCall);
+  if (auto ArgLoc = S.getConstraintSystem().getArgumentLocator(ParentCall)) {
+    if (auto FuncArgApplyInfo = S.getFunctionArgApplyInfo(ArgLoc)) {
+      Type ParamType = FuncArgApplyInfo->getParamInterfaceType();
+      ExpectedCallType = S.simplifyTypeForCodeCompletion(ParamType);
+    }
   }
-
+  if (!ExpectedCallType) {
+    if (auto ContextualType = S.getContextualType(ParentCall)) {
+      ExpectedCallType = ContextualType;
+    }
+  }
+  if (ExpectedCallType && ExpectedCallType->hasUnresolvedType()) {
+    ExpectedCallType = Type();
+  }
+  
   auto *CallLocator = CS.getConstraintLocator(ParentCall);
   auto *CalleeLocator = S.getCalleeLocator(CallLocator);
 

lib/Sema/CSApply.cpp

@@ -98,8 +98,15 @@ Solution::computeSubstitutions(NullablePtr<ValueDecl> decl,
   TypeSubstitutionMap subs;
   for (const auto &opened : openedTypes->second) {
     auto type = getFixedType(opened.second);
-    if (opened.first->isParameterPack() && !type->is<PackType>())
-      type = PackType::getSingletonPackExpansion(type);
+    if (opened.first->isParameterPack()) {
+      if (type->is<PlaceholderType>()) {
+        auto &ctx = type->getASTContext();
+        type =
+        PackType::get(ctx, {PackExpansionType::get(ctx.TheUnresolvedType,
+                                                   ctx.TheUnresolvedType)});
+      } else if (!type->is<PackType>())
+        type = PackType::getSingletonPackExpansion(type);
+    }
     subs[opened.first] = type;
   }
 

test/IDE/complete_call_arg.swift

@@ -576,17 +576,17 @@ func testStaticMemberCall() {
 func testImplicitMember() {
   let _: TestStaticMemberCall = .create1(#^IMPLICIT_MEMBER_AFTERPAREN_1^#)
 // IMPLICIT_MEMBER_AFTERPAREN_1: Begin completions, 1 items
-// IMPLICIT_MEMBER_AFTERPAREN_1: Decl[StaticMethod]/CurrNominal/Flair[ArgLabels]/TypeRelation[Convertible]: ['(']{#arg1: Int#}[')'][#TestStaticMemberCall#]; name=arg1:
+// IMPLICIT_MEMBER_AFTERPAREN_1: Decl[StaticMethod]/CurrNominal/Flair[ArgLabels]: ['(']{#arg1: Int#}[')'][#TestStaticMemberCall#]; name=arg1:
 
   let _: TestStaticMemberCall = .create2(#^IMPLICIT_MEMBER_AFTERPAREN_2^#)
-// IMPLICIT_MEMBER_AFTERPAREN_2-DAG: Decl[StaticMethod]/CurrNominal/Flair[ArgLabels]/TypeRelation[Convertible]: ['(']{#(arg1): Int#}[')'][#TestStaticMemberCall#];
-// IMPLICIT_MEMBER_AFTERPAREN_2-DAG: Decl[StaticMethod]/CurrNominal/Flair[ArgLabels]/TypeRelation[Convertible]: ['(']{#(arg1): Int#}, {#arg2: Int#}, {#arg3: Int#}, {#arg4: Int#}[')'][#TestStaticMemberCall#];
+// IMPLICIT_MEMBER_AFTERPAREN_2-DAG: Decl[StaticMethod]/CurrNominal/Flair[ArgLabels]: ['(']{#(arg1): Int#}[')'][#TestStaticMemberCall#];
+// IMPLICIT_MEMBER_AFTERPAREN_2-DAG: Decl[StaticMethod]/CurrNominal/Flair[ArgLabels]: ['(']{#(arg1): Int#}, {#arg2: Int#}, {#arg3: Int#}, {#arg4: Int#}[')'][#TestStaticMemberCall#];
 // IMPLICIT_MEMBER_AFTERPAREN_2-DAG: Decl[Struct]/OtherModule[Swift]/IsSystem/TypeRelation[Convertible]: Int[#Int#];
 // IMPLICIT_MEMBER_AFTERPAREN_2-DAG: Literal[Integer]/None/TypeRelation[Convertible]: 0[#Int#];
 
   let _: TestStaticMemberCall? = .create1(#^IMPLICIT_MEMBER_AFTERPAREN_3^#)
 // IMPLICIT_MEMBER_AFTERPAREN_3: Begin completions, 1 items
-// IMPLICIT_MEMBER_AFTERPAREN_3: Decl[StaticMethod]/CurrNominal/Flair[ArgLabels]/TypeRelation[Convertible]: ['(']{#arg1: Int#}[')'][#TestStaticMemberCall#]; name=arg1:
+// IMPLICIT_MEMBER_AFTERPAREN_3: Decl[StaticMethod]/CurrNominal/Flair[ArgLabels]: ['(']{#arg1: Int#}[')'][#TestStaticMemberCall#]; name=arg1:
 
   let _: TestStaticMemberCall = .create2(1, #^IMPLICIT_MEMBER_SECOND^#)
 // IMPLICIT_MEMBER_SECOND: Begin completions, 3 items
@@ -600,7 +600,7 @@ func testImplicitMember() {
 
   let _: TestStaticMemberCall = .createOverloaded(#^IMPLICIT_MEMBER_OVERLOADED^#)
 // IMPLICIT_MEMBER_OVERLOADED: Begin completions, 1 item
-// IMPLICIT_MEMBER_OVERLOADED: Decl[StaticMethod]/CurrNominal/Flair[ArgLabels]/TypeRelation[Convertible]: ['(']{#arg1: Int#}[')'][#TestStaticMemberCall#]; name=arg1:
+// IMPLICIT_MEMBER_OVERLOADED: Decl[StaticMethod]/CurrNominal/Flair[ArgLabels]: ['(']{#arg1: Int#}[')'][#TestStaticMemberCall#]; name=arg1:
 }
 func testImplicitMemberInArrayLiteral() {
   struct Receiver {
@@ -1325,8 +1325,8 @@ func testSubscriptWithExistingRhs(someString: String) {
 
 // SUBSCRIPT_WITH_EXISTING_RHS: Begin completions
 // SUBSCRIPT_WITH_EXISTING_RHS-DAG: Pattern/CurrNominal/Flair[ArgLabels]: ['[']{#keyPath: KeyPath<[String : Any], Value>#}[']'][#Value#];
-// SUBSCRIPT_WITH_EXISTING_RHS-DAG: Decl[Subscript]/CurrNominal/Flair[ArgLabels]/IsSystem/TypeRelation[Convertible]: ['[']{#(key): String#}[']'][#@lvalue Any?#];
-// SUBSCRIPT_WITH_EXISTING_RHS-DAG: Decl[Subscript]/CurrNominal/Flair[ArgLabels]/IsSystem/TypeRelation[Convertible]: ['[']{#(key): String#}, {#default: Any#}[']'][#@lvalue Any#];
+// SUBSCRIPT_WITH_EXISTING_RHS-DAG: Decl[Subscript]/CurrNominal/Flair[ArgLabels]/IsSystem: ['[']{#(key): String#}[']'][#@lvalue Any?#];
+// SUBSCRIPT_WITH_EXISTING_RHS-DAG: Decl[Subscript]/CurrNominal/Flair[ArgLabels]/IsSystem: ['[']{#(key): String#}, {#default: Any#}[']'][#@lvalue Any#];
 // SUBSCRIPT_WITH_EXISTING_RHS-DAG: Decl[LocalVar]/Local/TypeRelation[Convertible]: someString[#String#];
 // SUBSCRIPT_WITH_EXISTING_RHS: End completions
 }
@@ -1348,8 +1348,8 @@ func testOptionalConversionInSrcOfAssignment(myArray: [Int]) {
   var optInt: Int?
   optInt = myArray[#^OPTIONAL_CONVERSION_IN_ASSIGNMENT^#]
 // OPTIONAL_CONVERSION_IN_ASSIGNMENT: Begin completions
-// OPTIONAL_CONVERSION_IN_ASSIGNMENT-DAG: Pattern/CurrNominal/Flair[ArgLabels]/TypeRelation[Convertible]: ['[']{#keyPath: KeyPath<[Int], Value>#}[']'][#Value#]; name=keyPath:
-// OPTIONAL_CONVERSION_IN_ASSIGNMENT-DAG: Decl[Subscript]/CurrNominal/Flair[ArgLabels]/IsSystem/TypeRelation[Convertible]: ['[']{#(index): Int#}[']'][#Int#]; name=:
+// OPTIONAL_CONVERSION_IN_ASSIGNMENT-DAG: Pattern/CurrNominal/Flair[ArgLabels]: ['[']{#keyPath: KeyPath<[Int], Value>#}[']'][#Value#]; name=keyPath:
+// OPTIONAL_CONVERSION_IN_ASSIGNMENT-DAG: Decl[Subscript]/CurrNominal/Flair[ArgLabels]/IsSystem: ['[']{#(index): Int#}[']'][#Int#]; name=:
 // OPTIONAL_CONVERSION_IN_ASSIGNMENT-DAG: Literal[Integer]/None/TypeRelation[Convertible]: 0[#Int#]; name=0
 // OPTIONAL_CONVERSION_IN_ASSIGNMENT: End completions
 }
@@ -1359,7 +1359,7 @@ func testAnyConversionInDestOfAssignment(_ message: String) {
   userInfo[#^ANY_CONVERSION_IN_ASSIGNMENT^#] = message
 // ANY_CONVERSION_IN_ASSIGNMENT: Begin completions
 // ANY_CONVERSION_IN_ASSIGNMENT-DAG: Pattern/CurrNominal/Flair[ArgLabels]: ['[']{#keyPath: KeyPath<[String : Any], Value>#}[']'][#Value#]; name=keyPath:
-// ANY_CONVERSION_IN_ASSIGNMENT-DAG: Decl[Subscript]/CurrNominal/Flair[ArgLabels]/IsSystem/TypeRelation[Convertible]: ['[']{#(key): String#}, {#default: Any#}[']'][#@lvalue Any#]; name=:default:
+// ANY_CONVERSION_IN_ASSIGNMENT-DAG: Decl[Subscript]/CurrNominal/Flair[ArgLabels]/IsSystem: ['[']{#(key): String#}, {#default: Any#}[']'][#@lvalue Any#]; name=:default:
 // ANY_CONVERSION_IN_ASSIGNMENT-DAG: Decl[LocalVar]/Local:               userInfo[#[String : Any]#]; name=userInfo
 // ANY_CONVERSION_IN_ASSIGNMENT-DAG: Decl[LocalVar]/Local/TypeRelation[Convertible]: message[#String#]; name=message
 // ANY_CONVERSION_IN_ASSIGNMENT: End completions
@@ -1427,18 +1427,19 @@ struct NestedCallsWithoutClosingParen {
   func testInDictionaryLiteral() {
     let a = 1
     let b = 2
-    _ = [a: foo(#^IN_DICTIONARY_LITERAL?check=NESTED_CALL_AT_START^#, b: 1]
+    _ = [a: foo(#^IN_DICTIONARY_LITERAL?check=NESTED_CALL_WITHOUT_TYPE_RELATION^#, b: 1]
+      // NESTED_CALL_WITHOUT_TYPE_RELATION-DAG: Decl[InstanceMethod]/CurrNominal/Flair[ArgLabels]: ['(']{#arg: Int#}, {#arg2: Int#}[')'][#Int#];
   } 
 
   func testInArrayLiteral() {
-    _ = [foo(#^IN_ARRAY_LITERAL?check=NESTED_CALL_AT_START^#, 1]
+    _ = [foo(#^IN_ARRAY_LITERAL?check=NESTED_CALL_WITHOUT_TYPE_RELATION^#, 1]
   }
 
   func testInParen() {
-    _ = (foo(#^IN_PAREN?check=NESTED_CALL_AT_START^#)
+    _ = (foo(#^IN_PAREN?check=NESTED_CALL_WITHOUT_TYPE_RELATION^#)
   }
 
   func testInTuple() {
-    _ = (foo(#^IN_TUPLE?check=NESTED_CALL_AT_START^#, 1)
+    _ = (foo(#^IN_TUPLE?check=NESTED_CALL_WITHOUT_TYPE_RELATION^#, 1)
   }
 }

test/IDE/complete_dont_filter_overloads_with_cc_token.swift

@@ -18,7 +18,7 @@ func test(text: String) {
 }
 
 // COMPLETE: Begin completions
-// COMPLETE-DAG: Decl[Constructor]/CurrNominal/Flair[ArgLabels]/TypeRelation[Convertible]: ['(']{#verbatim: String#}[')'][#MyText#];
-// COMPLETE-DAG: Decl[Constructor]/CurrNominal/Flair[ArgLabels]/TypeRelation[Convertible]: ['(']{#(content): StringProtocol#}[')'][#MyText#];
+// COMPLETE-DAG: Decl[Constructor]/CurrNominal/Flair[ArgLabels]: ['(']{#verbatim: String#}[')'][#MyText#];
+// COMPLETE-DAG: Decl[Constructor]/CurrNominal/Flair[ArgLabels]: ['(']{#(content): StringProtocol#}[')'][#MyText#];
 // COMPLETE-DAG: Decl[LocalVar]/Local/TypeRelation[Convertible]: text[#String#];
 // COMPLETE: End completions

test/IDE/complete_enum_unresolved_dot_argument_labels.swift

@@ -10,15 +10,15 @@ func testInit() {
   var state = DragState.inactive
   state = .dragging(#^SIGNATURE^#)
   // SIGNATURE: Begin completions, 1 item
-  // SIGNATURE: Pattern/CurrNominal/Flair[ArgLabels]/TypeRelation[Convertible]: ['(']{#translationX: Int#}, {#translationY: Int#}[')'][#DragState#];
+  // SIGNATURE: Pattern/CurrNominal/Flair[ArgLabels]: ['(']{#translationX: Int#}, {#translationY: Int#}[')'][#DragState#];
 
   state = .dragging(translationX: 2, #^ARGUMENT^#)
   // ARGUMENT: Begin completions, 1 item
   // ARGUMENT: Pattern/Local/Flair[ArgLabels]: {#translationY: Int#}[#Int#];
 
   state = .defaulted(#^DEFAULTED^#)
   // DEFAULTED: Begin completions, 1 items
-  // DEFAULTED: Pattern/CurrNominal/Flair[ArgLabels]/TypeRelation[Convertible]: ['(']{#x: Int#}, {#y: Int#}, {#z: Int#}, {#extra: Int#}[')'][#DragState#];
+  // DEFAULTED: Pattern/CurrNominal/Flair[ArgLabels]: ['(']{#x: Int#}, {#y: Int#}, {#z: Int#}, {#extra: Int#}[')'][#DragState#];
 
   state = .defaulted(x: 1, #^DEFAULTEDARG^#)
   state = .defaulted(x: "Wrong type", #^ERRORTYPE?check=DEFAULTEDARG^#)

test/IDE/complete_in_result_builder.swift

@@ -134,7 +134,7 @@ func testCompleteFunctionArgumentLabels() {
   @TupleBuilder<String> var x1 {
     StringFactory.makeString(#^FUNCTION_ARGUMENT_LABEL^#)
     // FUNCTION_ARGUMENT_LABEL: Begin completions, 1 item
-    // FUNCTION_ARGUMENT_LABEL: Decl[StaticMethod]/CurrNominal/Flair[ArgLabels]/TypeRelation[Convertible]: ['(']{#x: String#}[')'][#String#];
+    // FUNCTION_ARGUMENT_LABEL: Decl[StaticMethod]/CurrNominal/Flair[ArgLabels]: ['(']{#x: String#}[')'][#String#];
   }
 }
 

test/IDE/complete_parameter_pack_as_call_argument.swift

@@ -0,0 +1,7 @@
+// RUN: %batch-code-completion
+
+struct Mixer<each Source: Signal>: Signal {}
+
+print(Mixer(#^COMPLETE^#))
+
+// COMPLETE: Decl[Constructor]/CurrNominal/Flair[ArgLabels]: ['('][')'][#Mixer<repeat each Source>#];

test/IDE/complete_subscript.swift

@@ -150,5 +150,5 @@ func testSettableSub(x: inout HasSettableSub) {
     x[#^SETTABLE_SUBSCRIPT^#] = 32
 }
 // SETTABLE_SUBSCRIPT-DAG: Pattern/CurrNominal/Flair[ArgLabels]: ['[']{#keyPath: KeyPath<HasSettableSub, Value>#}[']'][#Value#];
-// SETTABLE_SUBSCRIPT-DAG: Decl[Subscript]/CurrNominal/Flair[ArgLabels]/TypeRelation[Convertible]: ['[']{#(a): String#}[']'][#@lvalue Int#];
+// SETTABLE_SUBSCRIPT-DAG: Decl[Subscript]/CurrNominal/Flair[ArgLabels]: ['[']{#(a): String#}[']'][#@lvalue Int#];
 // SETTABLE_SUBSCRIPT-DAG: Decl[LocalVar]/Local/TypeRelation[Convertible]: local[#String#]; name=local

test/IDE/expected_type_of_call_pattern.swift

@@ -0,0 +1,15 @@
+// RUN: %batch-code-completion
+
+func foo(_ x: Int) {}
+
+struct Bar {
+  func bar(withString: String) -> String {}
+  func bar(withInt: Int) -> Int {}
+}
+
+func test() {
+  foo(Bar().bar(#^COMPLETE^#))
+}
+// Ensure that we don't report the call pattern for `bar` as `Convertible`
+// COMPLETE-DAG: Decl[InstanceMethod]/CurrNominal/Flair[ArgLabels]: ['(']{#withString: String#}[')'][#String#]; name=withString:
+// COMPLETE-DAG: Decl[InstanceMethod]/CurrNominal/Flair[ArgLabels]/TypeRelation[Convertible]: ['(']{#withInt: Int#}[')'][#Int#]; name=withInt:

validation-test/IDE/issues_fixed/issue-57149.swift

@@ -27,4 +27,4 @@ struct ContentView: View {
   }
 }
 
-// COMPLETE: Decl[InstanceMethod]/Super/Flair[ArgLabels]/TypeRelation[Convertible]: ['(']{#foo: Int#}[')'][#Never#]; name=foo:
+// COMPLETE: Decl[InstanceMethod]/Super/Flair[ArgLabels]: ['(']{#foo: Int#}[')'][#Never#]; name=foo: