Merge pull request #23845 from Azoy/sr-10313

[CSApply] Restructure the implicit AST when applying @dynamicCallable

Author: slavapestov

lib/Sema/CSApply.cpp

@@ -1108,6 +1108,10 @@ namespace {
     Expr *finishApply(ApplyExpr *apply, Type openedType,
                       ConstraintLocatorBuilder locator);
 
+    // Resolve @dynamicCallable applications.
+    Expr *finishApplyDynamicCallable(const Solution &solution, ApplyExpr *apply,
+                                     ConstraintLocatorBuilder locator);
+
   private:
     /// Simplify the given type by substituting all occurrences of
     /// type variables for their fixed types.
@@ -2041,9 +2045,6 @@ namespace {
     }
 
     Expr *handleStringLiteralExpr(LiteralExpr *expr) {
-      if (cs.getType(expr) && !cs.getType(expr)->hasTypeVariable())
-        return expr;
-      
       auto stringLiteral = dyn_cast<StringLiteralExpr>(expr);
       auto magicLiteral = dyn_cast<MagicIdentifierLiteralExpr>(expr);
       assert(bool(stringLiteral) != bool(magicLiteral) &&
@@ -7004,10 +7005,10 @@ Expr *ExprRewriter::convertLiteralInPlace(Expr *literal,
 }
 
 // Resolve @dynamicCallable applications.
-static Expr *finishApplyDynamicCallable(ConstraintSystem &cs,
-                                        const Solution &solution,
-                                        ApplyExpr *apply,
-                                        ConstraintLocatorBuilder locator) {
+Expr *
+ExprRewriter::finishApplyDynamicCallable(const Solution &solution,
+                                         ApplyExpr *apply,
+                                         ConstraintLocatorBuilder locator) {
   auto &ctx = cs.getASTContext();
   auto *fn = apply->getFn();
 
@@ -7019,12 +7020,14 @@ static Expr *finishApplyDynamicCallable(ConstraintSystem &cs,
   auto loc = locator.withPathElement(ConstraintLocator::ApplyFunction);
   auto selected = solution.getOverloadChoice(cs.getConstraintLocator(loc));
   auto *method = dyn_cast<FuncDecl>(selected.choice.getDecl());
-  auto methodType = selected.openedType->castTo<AnyFunctionType>();
+  auto methodType = simplifyType(selected.openedType)->castTo<AnyFunctionType>();
   assert(method->getName() == ctx.Id_dynamicallyCall &&
          "Expected 'dynamicallyCall' method");
-  assert(methodType->getParams().size() == 1 &&
+  auto params = methodType->getParams();
+  assert(params.size() == 1 &&
          "Expected 'dynamicallyCall' method with one parameter");
-  auto argumentLabel = methodType->getParams()[0].getLabel();
+  auto argumentType = params[0].getParameterType();
+  auto argumentLabel = params[0].getLabel();
   assert((argumentLabel == ctx.Id_withArguments ||
           argumentLabel == ctx.Id_withKeywordArguments) &&
          "Expected 'dynamicallyCall' method argument label 'withArguments' or "
@@ -7034,39 +7037,62 @@ static Expr *finishApplyDynamicCallable(ConstraintSystem &cs,
   // `withKeywordArguments` method.
   bool useKwargsMethod = argumentLabel == ctx.Id_withKeywordArguments;
 
-  // Construct expression referencing the `dynamicallyCall` method.
-  Expr *member =
-    new (ctx) MemberRefExpr(fn, fn->getEndLoc(), ConcreteDeclRef(method),
-                            DeclNameLoc(method->getNameLoc()),
-                            /*Implicit*/ true);
+  // Construct expression referencing the `dynamicallyCall` method.	
+  bool isDynamic =
+      selected.choice.getKind() == OverloadChoiceKind::DeclViaDynamic;
+  auto member = buildMemberRef(fn, selected.openedFullType,
+                               SourceLoc(), selected.choice,
+                               DeclNameLoc(method->getNameLoc()),
+                               selected.openedType, loc, loc, /*implicit*/ true,
+                               selected.choice.getFunctionRefKind(),
+                               AccessSemantics::Ordinary, isDynamic);
 
   // Construct argument to the method (either an array or dictionary
   // expression).
   Expr *argument = nullptr;
   if (!useKwargsMethod) {
     argument = ArrayExpr::create(ctx, SourceLoc(), arg->getElements(),
                                  {}, SourceLoc());
+    cs.setType(argument, argumentType);
+    finishArrayExpr(cast<ArrayExpr>(argument));
   } else {
+    auto dictLitProto =
+        ctx.getProtocol(KnownProtocolKind::ExpressibleByDictionaryLiteral);
+    auto conformance =
+        cs.TC.conformsToProtocol(argumentType, dictLitProto, cs.DC,
+                                 ConformanceCheckFlags::InExpression);
+    auto keyType = conformance->getTypeWitnessByName(argumentType, ctx.Id_Key);
+    auto valueType = conformance->getTypeWitnessByName(argumentType,
+                                                       ctx.Id_Value);
     SmallVector<Identifier, 4> names;
     SmallVector<Expr *, 4> dictElements;
     for (unsigned i = 0, n = arg->getNumElements(); i < n; i++) {
       Expr *labelExpr =
         new (ctx) StringLiteralExpr(arg->getElementName(i).get(),
                                     arg->getElementNameLoc(i),
                                     /*Implicit*/ true);
+      cs.setType(labelExpr, keyType);
+      handleStringLiteralExpr(cast<LiteralExpr>(labelExpr));
+
       Expr *pair =
         TupleExpr::createImplicit(ctx, { labelExpr, arg->getElement(i) }, {});
+      auto eltTypes = { TupleTypeElt(keyType), TupleTypeElt(valueType) };
+      cs.setType(pair, TupleType::get(eltTypes, ctx));
       dictElements.push_back(pair);
     }
     argument = DictionaryExpr::create(ctx, SourceLoc(), dictElements, {},
                                       SourceLoc());
+    cs.setType(argument, argumentType);
+    finishDictionaryExpr(cast<DictionaryExpr>(argument));
   }
   argument->setImplicit();
 
   // Construct call to the `dynamicallyCall` method.
-  Expr *result = CallExpr::createImplicit(ctx, member, argument,
-                                          { argumentLabel });
-  cs.TC.typeCheckExpression(result, cs.DC);
+  auto result = CallExpr::createImplicit(ctx, member, argument,
+                                         { argumentLabel });
+  cs.setType(result->getArg(), AnyFunctionType::composeInput(ctx, params,
+                                                             false));
+  cs.setType(result, methodType->getResult());
   cs.cacheExprTypes(result);
   return result;
 }
@@ -7367,7 +7393,7 @@ Expr *ExprRewriter::finishApply(ApplyExpr *apply, Type openedType,
 
   // Handle @dynamicCallable applications.
   // At this point, all other ApplyExpr cases have been handled.
-  return finishApplyDynamicCallable(cs, solution, apply, locator);
+  return finishApplyDynamicCallable(solution, apply, locator);
 }
 
 

test/attr/attr_dynamic_callable.swift

@@ -421,3 +421,49 @@ func testGenericType5<T>(a: CallableGeneric5<T>) -> Double {
 func testArchetypeType5<T, C : CallableGeneric5<T>>(a: C) -> Double {
   return a(1, 2, 3) + a(x1: 1, 2, x3: 3)
 }
+
+// SR-9239 Default argument in initializer
+
+@dynamicCallable
+struct A {
+  init(_ x: Int = 0) {}
+  func dynamicallyCall(withArguments args: [Int]) {}
+}
+
+func test9239() {
+  _ = A()() // ok
+}
+
+// SR-10313
+//
+// Modified version of the code snippet in the SR to not crash.
+
+struct MissingKeyError: Error {}
+
+@dynamicCallable
+class DictionaryBox {
+  var dictionary: [String: Any] = [:]
+
+  func dynamicallyCall<T>(withArguments args: [String]) throws -> T {
+    guard let value = dictionary[args[0]] as? T else {
+      throw MissingKeyError()
+    }
+    return value
+  }
+}
+
+func test10313() {
+  let box = DictionaryBox()
+  box.dictionary["bool"] = false
+  let _: Bool = try! box("bool") // ok
+}
+
+// SR-10753
+
+@dynamicCallable
+struct B {
+	public func dynamicallyCall(withArguments arguments: [String]) {}
+}
+
+B()("hello") // ok
+B()("\(1)") // ok