Update LKG

lib/tsc.js

@@ -5304,7 +5304,7 @@ var ts;
         The_left_hand_side_of_an_instanceof_expression_must_be_of_type_any_an_object_type_or_a_type_parameter: diag(2358, ts.DiagnosticCategory.Error, "The_left_hand_side_of_an_instanceof_expression_must_be_of_type_any_an_object_type_or_a_type_paramete_2358", "The left-hand side of an 'instanceof' expression must be of type 'any', an object type or a type parameter."),
         The_right_hand_side_of_an_instanceof_expression_must_be_of_type_any_or_of_a_type_assignable_to_the_Function_interface_type: diag(2359, ts.DiagnosticCategory.Error, "The_right_hand_side_of_an_instanceof_expression_must_be_of_type_any_or_of_a_type_assignable_to_the_F_2359", "The right-hand side of an 'instanceof' expression must be of type 'any' or of a type assignable to the 'Function' interface type."),
         The_left_hand_side_of_an_in_expression_must_be_of_type_any_string_number_or_symbol: diag(2360, ts.DiagnosticCategory.Error, "The_left_hand_side_of_an_in_expression_must_be_of_type_any_string_number_or_symbol_2360", "The left-hand side of an 'in' expression must be of type 'any', 'string', 'number', or 'symbol'."),
-        The_right_hand_side_of_an_in_expression_must_be_of_type_any_an_object_type_or_a_type_parameter: diag(2361, ts.DiagnosticCategory.Error, "The_right_hand_side_of_an_in_expression_must_be_of_type_any_an_object_type_or_a_type_parameter_2361", "The right-hand side of an 'in' expression must be of type 'any', an object type or a type parameter."),
+        The_right_hand_side_of_an_in_expression_must_not_be_a_primitive: diag(2361, ts.DiagnosticCategory.Error, "The_right_hand_side_of_an_in_expression_must_not_be_a_primitive_2361", "The right-hand side of an 'in' expression must not be a primitive."),
         The_left_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_bigint_or_an_enum_type: diag(2362, ts.DiagnosticCategory.Error, "The_left_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_bigint_or_an_enum_type_2362", "The left-hand side of an arithmetic operation must be of type 'any', 'number', 'bigint' or an enum type."),
         The_right_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_bigint_or_an_enum_type: diag(2363, ts.DiagnosticCategory.Error, "The_right_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_bigint_or_an_enum_type_2363", "The right-hand side of an arithmetic operation must be of type 'any', 'number', 'bigint' or an enum type."),
         The_left_hand_side_of_an_assignment_expression_must_be_a_variable_or_a_property_access: diag(2364, ts.DiagnosticCategory.Error, "The_left_hand_side_of_an_assignment_expression_must_be_a_variable_or_a_property_access_2364", "The left-hand side of an assignment expression must be a variable or a property access."),
@@ -45152,15 +45152,18 @@ var ts;
             type.resolvedTypeArguments = source.resolvedTypeArguments;
             return type;
         }
-        function createDeferredTypeReference(target, node, mapper) {
-            var aliasSymbol = getAliasSymbolForTypeNode(node);
-            var aliasTypeArguments = getTypeArgumentsForAliasSymbol(aliasSymbol);
+        function createDeferredTypeReference(target, node, mapper, aliasSymbol, aliasTypeArguments) {
+            if (!aliasSymbol) {
+                aliasSymbol = getAliasSymbolForTypeNode(node);
+                var localAliasTypeArguments = getTypeArgumentsForAliasSymbol(aliasSymbol);
+                aliasTypeArguments = mapper ? instantiateTypes(localAliasTypeArguments, mapper) : localAliasTypeArguments;
+            }
             var type = createObjectType(4, target.symbol);
             type.target = target;
             type.node = node;
             type.mapper = mapper;
             type.aliasSymbol = aliasSymbol;
-            type.aliasTypeArguments = mapper ? instantiateTypes(aliasTypeArguments, mapper) : aliasTypeArguments;
+            type.aliasTypeArguments = aliasTypeArguments;
             return type;
         }
         function getTypeArguments(type) {
@@ -45218,17 +45221,17 @@ var ts;
             }
             return checkNoTypeArguments(node, symbol) ? type : errorType;
         }
-        function getTypeAliasInstantiation(symbol, typeArguments) {
+        function getTypeAliasInstantiation(symbol, typeArguments, aliasSymbol, aliasTypeArguments) {
             var type = getDeclaredTypeOfSymbol(symbol);
             if (type === intrinsicMarkerType && intrinsicTypeKinds.has(symbol.escapedName) && typeArguments && typeArguments.length === 1) {
                 return getStringMappingType(symbol, typeArguments[0]);
             }
             var links = getSymbolLinks(symbol);
             var typeParameters = links.typeParameters;
-            var id = getTypeListId(typeArguments);
+            var id = getTypeListId(typeArguments) + (aliasSymbol ? "@" + getSymbolId(aliasSymbol) : "");
             var instantiation = links.instantiations.get(id);
             if (!instantiation) {
-                links.instantiations.set(id, instantiation = instantiateType(type, createTypeMapper(typeParameters, fillMissingTypeArguments(typeArguments, typeParameters, getMinTypeArgumentCount(typeParameters), ts.isInJSFile(symbol.valueDeclaration)))));
+                links.instantiations.set(id, instantiation = instantiateTypeWithAlias(type, createTypeMapper(typeParameters, fillMissingTypeArguments(typeArguments, typeParameters, getMinTypeArgumentCount(typeParameters), ts.isInJSFile(symbol.valueDeclaration))), aliasSymbol, aliasTypeArguments));
             }
             return instantiation;
         }
@@ -45244,7 +45247,8 @@ var ts;
                         ts.Diagnostics.Generic_type_0_requires_between_1_and_2_type_arguments, symbolToString(symbol), minTypeArgumentCount, typeParameters.length);
                     return errorType;
                 }
-                return getTypeAliasInstantiation(symbol, typeArgumentsFromTypeReferenceNode(node));
+                var aliasSymbol = getAliasSymbolForTypeNode(node);
+                return getTypeAliasInstantiation(symbol, typeArgumentsFromTypeReferenceNode(node), aliasSymbol, getTypeArgumentsForAliasSymbol(aliasSymbol));
             }
             return checkNoTypeArguments(node, symbol) ? type : errorType;
         }
@@ -47009,7 +47013,7 @@ var ts;
             }
             return type;
         }
-        function getConditionalType(root, mapper) {
+        function getConditionalType(root, mapper, aliasSymbol, aliasTypeArguments) {
             var result;
             var extraTypes;
             while (true) {
@@ -47055,8 +47059,8 @@ var ts;
                 result.extendsType = extendsType;
                 result.mapper = mapper;
                 result.combinedMapper = combinedMapper;
-                result.aliasSymbol = root.aliasSymbol;
-                result.aliasTypeArguments = instantiateTypes(root.aliasTypeArguments, mapper);
+                result.aliasSymbol = aliasSymbol || root.aliasSymbol;
+                result.aliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(root.aliasTypeArguments, mapper);
                 break;
             }
             return extraTypes ? getUnionType(ts.append(extraTypes, result)) : result;
@@ -47723,7 +47727,7 @@ var ts;
             }
             return result;
         }
-        function getObjectTypeInstantiation(type, mapper) {
+        function getObjectTypeInstantiation(type, mapper, aliasSymbol, aliasTypeArguments) {
             var declaration = type.objectFlags & 4 ? type.node : type.symbol.declarations[0];
             var links = getNodeLinks(declaration);
             var target = type.objectFlags & 4 ? links.resolvedType :
@@ -47744,17 +47748,19 @@ var ts;
             if (typeParameters.length) {
                 var combinedMapper_1 = combineTypeMappers(type.mapper, mapper);
                 var typeArguments = ts.map(typeParameters, function (t) { return getMappedType(t, combinedMapper_1); });
-                var id = getTypeListId(typeArguments);
+                var newAliasSymbol = aliasSymbol || type.aliasSymbol;
+                var id = getTypeListId(typeArguments) + (newAliasSymbol ? "@" + getSymbolId(newAliasSymbol) : "");
                 if (!target.instantiations) {
                     target.instantiations = new ts.Map();
-                    target.instantiations.set(getTypeListId(typeParameters), target);
+                    target.instantiations.set(getTypeListId(typeParameters) + (target.aliasSymbol ? "@" + getSymbolId(target.aliasSymbol) : ""), target);
                 }
                 var result = target.instantiations.get(id);
                 if (!result) {
                     var newMapper = createTypeMapper(typeParameters, typeArguments);
-                    result = target.objectFlags & 4 ? createDeferredTypeReference(type.target, type.node, newMapper) :
-                        target.objectFlags & 32 ? instantiateMappedType(target, newMapper) :
-                            instantiateAnonymousType(target, newMapper);
+                    var newAliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(type.aliasTypeArguments, mapper);
+                    result = target.objectFlags & 4 ? createDeferredTypeReference(type.target, type.node, newMapper, newAliasSymbol, newAliasTypeArguments) :
+                        target.objectFlags & 32 ? instantiateMappedType(target, newMapper, newAliasSymbol, newAliasTypeArguments) :
+                            instantiateAnonymousType(target, newMapper, newAliasSymbol, newAliasTypeArguments);
                     target.instantiations.set(id, result);
                 }
                 return result;
@@ -47800,12 +47806,12 @@ var ts;
             }
             return undefined;
         }
-        function instantiateMappedType(type, mapper) {
+        function instantiateMappedType(type, mapper, aliasSymbol, aliasTypeArguments) {
             var typeVariable = getHomomorphicTypeVariable(type);
             if (typeVariable) {
                 var mappedTypeVariable = instantiateType(typeVariable, mapper);
                 if (typeVariable !== mappedTypeVariable) {
-                    return mapType(getReducedType(mappedTypeVariable), function (t) {
+                    return mapTypeWithAlias(getReducedType(mappedTypeVariable), function (t) {
                         if (t.flags & (3 | 58982400 | 524288 | 2097152) && t !== wildcardType && t !== errorType) {
                             if (!type.declaration.nameType) {
                                 if (isArrayType(t)) {
@@ -47821,10 +47827,10 @@ var ts;
                             return instantiateAnonymousType(type, prependTypeMapping(typeVariable, t, mapper));
                         }
                         return t;
-                    });
+                    }, aliasSymbol, aliasTypeArguments);
                 }
             }
-            return instantiateType(getConstraintTypeFromMappedType(type), mapper) === wildcardType ? wildcardType : instantiateAnonymousType(type, mapper);
+            return instantiateType(getConstraintTypeFromMappedType(type), mapper) === wildcardType ? wildcardType : instantiateAnonymousType(type, mapper, aliasSymbol, aliasTypeArguments);
         }
         function getModifiedReadonlyState(state, modifiers) {
             return modifiers & 1 ? true : modifiers & 2 ? false : state;
@@ -47866,7 +47872,7 @@ var ts;
                 strictNullChecks && modifiers & 8 && isOptional ? getTypeWithFacts(propType, 524288) :
                     propType;
         }
-        function instantiateAnonymousType(type, mapper) {
+        function instantiateAnonymousType(type, mapper, aliasSymbol, aliasTypeArguments) {
             var result = createObjectType(type.objectFlags | 64, type.symbol);
             if (type.objectFlags & 32) {
                 result.declaration = type.declaration;
@@ -47878,37 +47884,40 @@ var ts;
             }
             result.target = type;
             result.mapper = mapper;
-            result.aliasSymbol = type.aliasSymbol;
-            result.aliasTypeArguments = instantiateTypes(type.aliasTypeArguments, mapper);
+            result.aliasSymbol = aliasSymbol || type.aliasSymbol;
+            result.aliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(type.aliasTypeArguments, mapper);
             return result;
         }
-        function getConditionalTypeInstantiation(type, mapper) {
+        function getConditionalTypeInstantiation(type, mapper, aliasSymbol, aliasTypeArguments) {
             var root = type.root;
             if (root.outerTypeParameters) {
                 var typeArguments = ts.map(root.outerTypeParameters, function (t) { return getMappedType(t, mapper); });
-                var id = getTypeListId(typeArguments);
+                var id = getTypeListId(typeArguments) + (aliasSymbol ? "@" + getSymbolId(aliasSymbol) : "");
                 var result = root.instantiations.get(id);
                 if (!result) {
                     var newMapper = createTypeMapper(root.outerTypeParameters, typeArguments);
-                    result = instantiateConditionalType(root, newMapper);
+                    result = instantiateConditionalType(root, newMapper, aliasSymbol, aliasTypeArguments);
                     root.instantiations.set(id, result);
                 }
                 return result;
             }
             return type;
         }
-        function instantiateConditionalType(root, mapper) {
+        function instantiateConditionalType(root, mapper, aliasSymbol, aliasTypeArguments) {
             if (root.isDistributive) {
                 var checkType_1 = root.checkType;
                 var instantiatedType = getMappedType(checkType_1, mapper);
                 if (checkType_1 !== instantiatedType && instantiatedType.flags & (1048576 | 131072)) {
-                    return mapType(instantiatedType, function (t) { return getConditionalType(root, prependTypeMapping(checkType_1, t, mapper)); });
+                    return mapTypeWithAlias(instantiatedType, function (t) { return getConditionalType(root, prependTypeMapping(checkType_1, t, mapper)); }, aliasSymbol, aliasTypeArguments);
                 }
             }
-            return getConditionalType(root, mapper);
+            return getConditionalType(root, mapper, aliasSymbol, aliasTypeArguments);
         }
         function instantiateType(type, mapper) {
-            if (!(type && mapper && couldContainTypeVariables(type))) {
+            return type && mapper ? instantiateTypeWithAlias(type, mapper, undefined, undefined) : type;
+        }
+        function instantiateTypeWithAlias(type, mapper, aliasSymbol, aliasTypeArguments) {
+            if (!couldContainTypeVariables(type)) {
                 return type;
             }
             if (instantiationDepth === 50 || instantiationCount >= 5000000) {
@@ -47919,11 +47928,11 @@ var ts;
             totalInstantiationCount++;
             instantiationCount++;
             instantiationDepth++;
-            var result = instantiateTypeWorker(type, mapper);
+            var result = instantiateTypeWorker(type, mapper, aliasSymbol, aliasTypeArguments);
             instantiationDepth--;
             return result;
         }
-        function instantiateTypeWorker(type, mapper) {
+        function instantiateTypeWorker(type, mapper, aliasSymbol, aliasTypeArguments) {
             var flags = type.flags;
             if (flags & 262144) {
                 return getMappedType(type, mapper);
@@ -47931,12 +47940,12 @@ var ts;
             if (flags & 524288) {
                 var objectFlags = type.objectFlags;
                 if (objectFlags & (4 | 16 | 32)) {
-                    if (objectFlags & 4 && !(type.node)) {
+                    if (objectFlags & 4 && !type.node) {
                         var resolvedTypeArguments = type.resolvedTypeArguments;
                         var newTypeArguments = instantiateTypes(resolvedTypeArguments, mapper);
                         return newTypeArguments !== resolvedTypeArguments ? createNormalizedTypeReference(type.target, newTypeArguments) : type;
                     }
-                    return getObjectTypeInstantiation(type, mapper);
+                    return getObjectTypeInstantiation(type, mapper, aliasSymbol, aliasTypeArguments);
                 }
                 return type;
             }
@@ -47944,10 +47953,14 @@ var ts;
                 var origin = type.flags & 1048576 ? type.origin : undefined;
                 var types = origin && origin.flags & 3145728 ? origin.types : type.types;
                 var newTypes = instantiateTypes(types, mapper);
-                return newTypes === types ? type :
-                    flags & 2097152 || origin && origin.flags & 2097152 ?
-                        getIntersectionType(newTypes, type.aliasSymbol, instantiateTypes(type.aliasTypeArguments, mapper)) :
-                        getUnionType(newTypes, 1, type.aliasSymbol, instantiateTypes(type.aliasTypeArguments, mapper));
+                if (newTypes === types && aliasSymbol === type.aliasSymbol) {
+                    return type;
+                }
+                var newAliasSymbol = aliasSymbol || type.aliasSymbol;
+                var newAliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(type.aliasTypeArguments, mapper);
+                return flags & 2097152 || origin && origin.flags & 2097152 ?
+                    getIntersectionType(newTypes, newAliasSymbol, newAliasTypeArguments) :
+                    getUnionType(newTypes, 1, newAliasSymbol, newAliasTypeArguments);
             }
             if (flags & 4194304) {
                 return getIndexType(instantiateType(type.type, mapper));
@@ -47959,10 +47972,12 @@ var ts;
                 return getStringMappingType(type.symbol, instantiateType(type.type, mapper));
             }
             if (flags & 8388608) {
-                return getIndexedAccessType(instantiateType(type.objectType, mapper), instantiateType(type.indexType, mapper), type.noUncheckedIndexedAccessCandidate, undefined, type.aliasSymbol, instantiateTypes(type.aliasTypeArguments, mapper));
+                var newAliasSymbol = aliasSymbol || type.aliasSymbol;
+                var newAliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(type.aliasTypeArguments, mapper);
+                return getIndexedAccessType(instantiateType(type.objectType, mapper), instantiateType(type.indexType, mapper), type.noUncheckedIndexedAccessCandidate, undefined, newAliasSymbol, newAliasTypeArguments);
             }
             if (flags & 16777216) {
-                return getConditionalTypeInstantiation(type, combineTypeMappers(type.mapper, mapper));
+                return getConditionalTypeInstantiation(type, combineTypeMappers(type.mapper, mapper), aliasSymbol, aliasTypeArguments);
             }
             if (flags & 33554432) {
                 var maybeVariable = instantiateType(type.baseType, mapper);
@@ -52882,6 +52897,11 @@ var ts;
             }
             return changed ? mappedTypes && getUnionType(mappedTypes, noReductions ? 0 : 1) : type;
         }
+        function mapTypeWithAlias(type, mapper, aliasSymbol, aliasTypeArguments) {
+            return type.flags & 1048576 && aliasSymbol ?
+                getUnionType(ts.map(type.types, mapper), 1, aliasSymbol, aliasTypeArguments) :
+                mapType(type, mapper);
+        }
         function getConstituentCount(type) {
             return type.flags & 3145728 ? type.types.length : 1;
         }
@@ -53011,10 +53031,15 @@ var ts;
                         return getExplicitThisType(node);
                     case 105:
                         return checkSuperExpression(node);
-                    case 201:
+                    case 201: {
                         var type = getTypeOfDottedName(node.expression, diagnostic);
-                        var prop = type && getPropertyOfType(type, node.name.escapedText);
-                        return prop && getExplicitTypeOfSymbol(prop, diagnostic);
+                        if (type) {
+                            var name = node.name;
+                            var prop = getPropertyOfType(type, ts.isPrivateIdentifier(name) ? ts.getSymbolNameForPrivateIdentifier(type.symbol, name.escapedText) : name.escapedText);
+                            return prop && getExplicitTypeOfSymbol(prop, diagnostic);
+                        }
+                        return undefined;
+                    }
                     case 207:
                         return getTypeOfDottedName(node.expression, diagnostic);
                 }
@@ -59551,8 +59576,11 @@ var ts;
                 isTypeAssignableToKind(leftType, 4194304 | 134217728 | 268435456 | 262144))) {
                 error(left, ts.Diagnostics.The_left_hand_side_of_an_in_expression_must_be_of_type_any_string_number_or_symbol);
             }
-            if (!allTypesAssignableToKind(rightType, 67108864 | 58982400)) {
-                error(right, ts.Diagnostics.The_right_hand_side_of_an_in_expression_must_be_of_type_any_an_object_type_or_a_type_parameter);
+            var rightTypeConstraint = getConstraintOfType(rightType);
+            if (!allTypesAssignableToKind(rightType, 67108864 | 58982400) ||
+                rightTypeConstraint && (isTypeAssignableToKind(rightType, 3145728) && !allTypesAssignableToKind(rightTypeConstraint, 67108864 | 58982400) ||
+                    !maybeTypeOfKind(rightTypeConstraint, 67108864 | 58982400 | 524288))) {
+                error(right, ts.Diagnostics.The_right_hand_side_of_an_in_expression_must_not_be_a_primitive);
             }
             return booleanType;
         }

lib/tsserver.js

@@ -7979,7 +7979,7 @@ var ts;
         The_left_hand_side_of_an_instanceof_expression_must_be_of_type_any_an_object_type_or_a_type_parameter: diag(2358, ts.DiagnosticCategory.Error, "The_left_hand_side_of_an_instanceof_expression_must_be_of_type_any_an_object_type_or_a_type_paramete_2358", "The left-hand side of an 'instanceof' expression must be of type 'any', an object type or a type parameter."),
         The_right_hand_side_of_an_instanceof_expression_must_be_of_type_any_or_of_a_type_assignable_to_the_Function_interface_type: diag(2359, ts.DiagnosticCategory.Error, "The_right_hand_side_of_an_instanceof_expression_must_be_of_type_any_or_of_a_type_assignable_to_the_F_2359", "The right-hand side of an 'instanceof' expression must be of type 'any' or of a type assignable to the 'Function' interface type."),
         The_left_hand_side_of_an_in_expression_must_be_of_type_any_string_number_or_symbol: diag(2360, ts.DiagnosticCategory.Error, "The_left_hand_side_of_an_in_expression_must_be_of_type_any_string_number_or_symbol_2360", "The left-hand side of an 'in' expression must be of type 'any', 'string', 'number', or 'symbol'."),
-        The_right_hand_side_of_an_in_expression_must_be_of_type_any_an_object_type_or_a_type_parameter: diag(2361, ts.DiagnosticCategory.Error, "The_right_hand_side_of_an_in_expression_must_be_of_type_any_an_object_type_or_a_type_parameter_2361", "The right-hand side of an 'in' expression must be of type 'any', an object type or a type parameter."),
+        The_right_hand_side_of_an_in_expression_must_not_be_a_primitive: diag(2361, ts.DiagnosticCategory.Error, "The_right_hand_side_of_an_in_expression_must_not_be_a_primitive_2361", "The right-hand side of an 'in' expression must not be a primitive."),
         The_left_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_bigint_or_an_enum_type: diag(2362, ts.DiagnosticCategory.Error, "The_left_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_bigint_or_an_enum_type_2362", "The left-hand side of an arithmetic operation must be of type 'any', 'number', 'bigint' or an enum type."),
         The_right_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_bigint_or_an_enum_type: diag(2363, ts.DiagnosticCategory.Error, "The_right_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_bigint_or_an_enum_type_2363", "The right-hand side of an arithmetic operation must be of type 'any', 'number', 'bigint' or an enum type."),
         The_left_hand_side_of_an_assignment_expression_must_be_a_variable_or_a_property_access: diag(2364, ts.DiagnosticCategory.Error, "The_left_hand_side_of_an_assignment_expression_must_be_a_variable_or_a_property_access_2364", "The left-hand side of an assignment expression must be a variable or a property access."),
@@ -54686,15 +54686,18 @@ var ts;
             type.resolvedTypeArguments = source.resolvedTypeArguments;
             return type;
         }
-        function createDeferredTypeReference(target, node, mapper) {
-            var aliasSymbol = getAliasSymbolForTypeNode(node);
-            var aliasTypeArguments = getTypeArgumentsForAliasSymbol(aliasSymbol);
+        function createDeferredTypeReference(target, node, mapper, aliasSymbol, aliasTypeArguments) {
+            if (!aliasSymbol) {
+                aliasSymbol = getAliasSymbolForTypeNode(node);
+                var localAliasTypeArguments = getTypeArgumentsForAliasSymbol(aliasSymbol);
+                aliasTypeArguments = mapper ? instantiateTypes(localAliasTypeArguments, mapper) : localAliasTypeArguments;
+            }
             var type = createObjectType(4 /* Reference */, target.symbol);
             type.target = target;
             type.node = node;
             type.mapper = mapper;
             type.aliasSymbol = aliasSymbol;
-            type.aliasTypeArguments = mapper ? instantiateTypes(aliasTypeArguments, mapper) : aliasTypeArguments;
+            type.aliasTypeArguments = aliasTypeArguments;
             return type;
         }
         function getTypeArguments(type) {
@@ -54759,17 +54762,17 @@ var ts;
             }
             return checkNoTypeArguments(node, symbol) ? type : errorType;
         }
-        function getTypeAliasInstantiation(symbol, typeArguments) {
+        function getTypeAliasInstantiation(symbol, typeArguments, aliasSymbol, aliasTypeArguments) {
             var type = getDeclaredTypeOfSymbol(symbol);
             if (type === intrinsicMarkerType && intrinsicTypeKinds.has(symbol.escapedName) && typeArguments && typeArguments.length === 1) {
                 return getStringMappingType(symbol, typeArguments[0]);
             }
             var links = getSymbolLinks(symbol);
             var typeParameters = links.typeParameters;
-            var id = getTypeListId(typeArguments);
+            var id = getTypeListId(typeArguments) + (aliasSymbol ? "@" + getSymbolId(aliasSymbol) : "");
             var instantiation = links.instantiations.get(id);
             if (!instantiation) {
-                links.instantiations.set(id, instantiation = instantiateType(type, createTypeMapper(typeParameters, fillMissingTypeArguments(typeArguments, typeParameters, getMinTypeArgumentCount(typeParameters), ts.isInJSFile(symbol.valueDeclaration)))));
+                links.instantiations.set(id, instantiation = instantiateTypeWithAlias(type, createTypeMapper(typeParameters, fillMissingTypeArguments(typeArguments, typeParameters, getMinTypeArgumentCount(typeParameters), ts.isInJSFile(symbol.valueDeclaration))), aliasSymbol, aliasTypeArguments));
             }
             return instantiation;
         }
@@ -54790,7 +54793,8 @@ var ts;
                         ts.Diagnostics.Generic_type_0_requires_between_1_and_2_type_arguments, symbolToString(symbol), minTypeArgumentCount, typeParameters.length);
                     return errorType;
                 }
-                return getTypeAliasInstantiation(symbol, typeArgumentsFromTypeReferenceNode(node));
+                var aliasSymbol = getAliasSymbolForTypeNode(node);
+                return getTypeAliasInstantiation(symbol, typeArgumentsFromTypeReferenceNode(node), aliasSymbol, getTypeArgumentsForAliasSymbol(aliasSymbol));
             }
             return checkNoTypeArguments(node, symbol) ? type : errorType;
         }
@@ -55892,7 +55896,7 @@ var ts;
             var result = createType(2097152 /* Intersection */);
             result.objectFlags = getPropagatingFlagsOfTypes(types, /*excludeKinds*/ 98304 /* Nullable */);
             result.types = types;
-            result.aliasSymbol = aliasSymbol; // See comment in `getUnionTypeFromSortedList`.
+            result.aliasSymbol = aliasSymbol;
             result.aliasTypeArguments = aliasTypeArguments;
             return result;
         }
@@ -56734,7 +56738,7 @@ var ts;
             }
             return type;
         }
-        function getConditionalType(root, mapper) {
+        function getConditionalType(root, mapper, aliasSymbol, aliasTypeArguments) {
             var result;
             var extraTypes;
             // We loop here for an immediately nested conditional type in the false position, effectively treating
@@ -56801,8 +56805,8 @@ var ts;
                 result.extendsType = extendsType;
                 result.mapper = mapper;
                 result.combinedMapper = combinedMapper;
-                result.aliasSymbol = root.aliasSymbol;
-                result.aliasTypeArguments = instantiateTypes(root.aliasTypeArguments, mapper); // TODO: GH#18217
+                result.aliasSymbol = aliasSymbol || root.aliasSymbol;
+                result.aliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(root.aliasTypeArguments, mapper); // TODO: GH#18217
                 break;
             }
             return extraTypes ? getUnionType(ts.append(extraTypes, result)) : result;
@@ -57518,7 +57522,7 @@ var ts;
             }
             return result;
         }
-        function getObjectTypeInstantiation(type, mapper) {
+        function getObjectTypeInstantiation(type, mapper, aliasSymbol, aliasTypeArguments) {
             var declaration = type.objectFlags & 4 /* Reference */ ? type.node : type.symbol.declarations[0];
             var links = getNodeLinks(declaration);
             var target = type.objectFlags & 4 /* Reference */ ? links.resolvedType :
@@ -57546,17 +57550,19 @@ var ts;
                 // instantiation cache key from the type IDs of the type arguments.
                 var combinedMapper_1 = combineTypeMappers(type.mapper, mapper);
                 var typeArguments = ts.map(typeParameters, function (t) { return getMappedType(t, combinedMapper_1); });
-                var id = getTypeListId(typeArguments);
+                var newAliasSymbol = aliasSymbol || type.aliasSymbol;
+                var id = getTypeListId(typeArguments) + (newAliasSymbol ? "@" + getSymbolId(newAliasSymbol) : "");
                 if (!target.instantiations) {
                     target.instantiations = new ts.Map();
-                    target.instantiations.set(getTypeListId(typeParameters), target);
+                    target.instantiations.set(getTypeListId(typeParameters) + (target.aliasSymbol ? "@" + getSymbolId(target.aliasSymbol) : ""), target);
                 }
                 var result = target.instantiations.get(id);
                 if (!result) {
                     var newMapper = createTypeMapper(typeParameters, typeArguments);
-                    result = target.objectFlags & 4 /* Reference */ ? createDeferredTypeReference(type.target, type.node, newMapper) :
-                        target.objectFlags & 32 /* Mapped */ ? instantiateMappedType(target, newMapper) :
-                            instantiateAnonymousType(target, newMapper);
+                    var newAliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(type.aliasTypeArguments, mapper);
+                    result = target.objectFlags & 4 /* Reference */ ? createDeferredTypeReference(type.target, type.node, newMapper, newAliasSymbol, newAliasTypeArguments) :
+                        target.objectFlags & 32 /* Mapped */ ? instantiateMappedType(target, newMapper, newAliasSymbol, newAliasTypeArguments) :
+                            instantiateAnonymousType(target, newMapper, newAliasSymbol, newAliasTypeArguments);
                     target.instantiations.set(id, result);
                 }
                 return result;
@@ -57605,7 +57611,7 @@ var ts;
             }
             return undefined;
         }
-        function instantiateMappedType(type, mapper) {
+        function instantiateMappedType(type, mapper, aliasSymbol, aliasTypeArguments) {
             // For a homomorphic mapped type { [P in keyof T]: X }, where T is some type variable, the mapping
             // operation depends on T as follows:
             // * If T is a primitive type no mapping is performed and the result is simply T.
@@ -57620,7 +57626,7 @@ var ts;
             if (typeVariable) {
                 var mappedTypeVariable = instantiateType(typeVariable, mapper);
                 if (typeVariable !== mappedTypeVariable) {
-                    return mapType(getReducedType(mappedTypeVariable), function (t) {
+                    return mapTypeWithAlias(getReducedType(mappedTypeVariable), function (t) {
                         if (t.flags & (3 /* AnyOrUnknown */ | 58982400 /* InstantiableNonPrimitive */ | 524288 /* Object */ | 2097152 /* Intersection */) && t !== wildcardType && t !== errorType) {
                             if (!type.declaration.nameType) {
                                 if (isArrayType(t)) {
@@ -57636,11 +57642,11 @@ var ts;
                             return instantiateAnonymousType(type, prependTypeMapping(typeVariable, t, mapper));
                         }
                         return t;
-                    });
+                    }, aliasSymbol, aliasTypeArguments);
                 }
             }
             // If the constraint type of the instantiation is the wildcard type, return the wildcard type.
-            return instantiateType(getConstraintTypeFromMappedType(type), mapper) === wildcardType ? wildcardType : instantiateAnonymousType(type, mapper);
+            return instantiateType(getConstraintTypeFromMappedType(type), mapper) === wildcardType ? wildcardType : instantiateAnonymousType(type, mapper, aliasSymbol, aliasTypeArguments);
         }
         function getModifiedReadonlyState(state, modifiers) {
             return modifiers & 1 /* IncludeReadonly */ ? true : modifiers & 2 /* ExcludeReadonly */ ? false : state;
@@ -57687,7 +57693,7 @@ var ts;
                 strictNullChecks && modifiers & 8 /* ExcludeOptional */ && isOptional ? getTypeWithFacts(propType, 524288 /* NEUndefined */) :
                     propType;
         }
-        function instantiateAnonymousType(type, mapper) {
+        function instantiateAnonymousType(type, mapper, aliasSymbol, aliasTypeArguments) {
             var result = createObjectType(type.objectFlags | 64 /* Instantiated */, type.symbol);
             if (type.objectFlags & 32 /* Mapped */) {
                 result.declaration = type.declaration;
@@ -57700,29 +57706,29 @@ var ts;
             }
             result.target = type;
             result.mapper = mapper;
-            result.aliasSymbol = type.aliasSymbol;
-            result.aliasTypeArguments = instantiateTypes(type.aliasTypeArguments, mapper);
+            result.aliasSymbol = aliasSymbol || type.aliasSymbol;
+            result.aliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(type.aliasTypeArguments, mapper);
             return result;
         }
-        function getConditionalTypeInstantiation(type, mapper) {
+        function getConditionalTypeInstantiation(type, mapper, aliasSymbol, aliasTypeArguments) {
             var root = type.root;
             if (root.outerTypeParameters) {
                 // We are instantiating a conditional type that has one or more type parameters in scope. Apply the
                 // mapper to the type parameters to produce the effective list of type arguments, and compute the
                 // instantiation cache key from the type IDs of the type arguments.
                 var typeArguments = ts.map(root.outerTypeParameters, function (t) { return getMappedType(t, mapper); });
-                var id = getTypeListId(typeArguments);
+                var id = getTypeListId(typeArguments) + (aliasSymbol ? "@" + getSymbolId(aliasSymbol) : "");
                 var result = root.instantiations.get(id);
                 if (!result) {
                     var newMapper = createTypeMapper(root.outerTypeParameters, typeArguments);
-                    result = instantiateConditionalType(root, newMapper);
+                    result = instantiateConditionalType(root, newMapper, aliasSymbol, aliasTypeArguments);
                     root.instantiations.set(id, result);
                 }
                 return result;
             }
             return type;
         }
-        function instantiateConditionalType(root, mapper) {
+        function instantiateConditionalType(root, mapper, aliasSymbol, aliasTypeArguments) {
             // Check if we have a conditional type where the check type is a naked type parameter. If so,
             // the conditional type is distributive over union types and when T is instantiated to a union
             // type A | B, we produce (A extends U ? X : Y) | (B extends U ? X : Y).
@@ -57730,13 +57736,16 @@ var ts;
                 var checkType_1 = root.checkType;
                 var instantiatedType = getMappedType(checkType_1, mapper);
                 if (checkType_1 !== instantiatedType && instantiatedType.flags & (1048576 /* Union */ | 131072 /* Never */)) {
-                    return mapType(instantiatedType, function (t) { return getConditionalType(root, prependTypeMapping(checkType_1, t, mapper)); });
+                    return mapTypeWithAlias(instantiatedType, function (t) { return getConditionalType(root, prependTypeMapping(checkType_1, t, mapper)); }, aliasSymbol, aliasTypeArguments);
                 }
             }
-            return getConditionalType(root, mapper);
+            return getConditionalType(root, mapper, aliasSymbol, aliasTypeArguments);
         }
         function instantiateType(type, mapper) {
-            if (!(type && mapper && couldContainTypeVariables(type))) {
+            return type && mapper ? instantiateTypeWithAlias(type, mapper, /*aliasSymbol*/ undefined, /*aliasTypeArguments*/ undefined) : type;
+        }
+        function instantiateTypeWithAlias(type, mapper, aliasSymbol, aliasTypeArguments) {
+            if (!couldContainTypeVariables(type)) {
                 return type;
             }
             if (instantiationDepth === 50 || instantiationCount >= 5000000) {
@@ -57750,11 +57759,11 @@ var ts;
             totalInstantiationCount++;
             instantiationCount++;
             instantiationDepth++;
-            var result = instantiateTypeWorker(type, mapper);
+            var result = instantiateTypeWorker(type, mapper, aliasSymbol, aliasTypeArguments);
             instantiationDepth--;
             return result;
         }
-        function instantiateTypeWorker(type, mapper) {
+        function instantiateTypeWorker(type, mapper, aliasSymbol, aliasTypeArguments) {
             var flags = type.flags;
             if (flags & 262144 /* TypeParameter */) {
                 return getMappedType(type, mapper);
@@ -57762,12 +57771,12 @@ var ts;
             if (flags & 524288 /* Object */) {
                 var objectFlags = type.objectFlags;
                 if (objectFlags & (4 /* Reference */ | 16 /* Anonymous */ | 32 /* Mapped */)) {
-                    if (objectFlags & 4 /* Reference */ && !(type.node)) {
+                    if (objectFlags & 4 /* Reference */ && !type.node) {
                         var resolvedTypeArguments = type.resolvedTypeArguments;
                         var newTypeArguments = instantiateTypes(resolvedTypeArguments, mapper);
                         return newTypeArguments !== resolvedTypeArguments ? createNormalizedTypeReference(type.target, newTypeArguments) : type;
                     }
-                    return getObjectTypeInstantiation(type, mapper);
+                    return getObjectTypeInstantiation(type, mapper, aliasSymbol, aliasTypeArguments);
                 }
                 return type;
             }
@@ -57775,10 +57784,14 @@ var ts;
                 var origin = type.flags & 1048576 /* Union */ ? type.origin : undefined;
                 var types = origin && origin.flags & 3145728 /* UnionOrIntersection */ ? origin.types : type.types;
                 var newTypes = instantiateTypes(types, mapper);
-                return newTypes === types ? type :
-                    flags & 2097152 /* Intersection */ || origin && origin.flags & 2097152 /* Intersection */ ?
-                        getIntersectionType(newTypes, type.aliasSymbol, instantiateTypes(type.aliasTypeArguments, mapper)) :
-                        getUnionType(newTypes, 1 /* Literal */, type.aliasSymbol, instantiateTypes(type.aliasTypeArguments, mapper));
+                if (newTypes === types && aliasSymbol === type.aliasSymbol) {
+                    return type;
+                }
+                var newAliasSymbol = aliasSymbol || type.aliasSymbol;
+                var newAliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(type.aliasTypeArguments, mapper);
+                return flags & 2097152 /* Intersection */ || origin && origin.flags & 2097152 /* Intersection */ ?
+                    getIntersectionType(newTypes, newAliasSymbol, newAliasTypeArguments) :
+                    getUnionType(newTypes, 1 /* Literal */, newAliasSymbol, newAliasTypeArguments);
             }
             if (flags & 4194304 /* Index */) {
                 return getIndexType(instantiateType(type.type, mapper));
@@ -57790,10 +57803,12 @@ var ts;
                 return getStringMappingType(type.symbol, instantiateType(type.type, mapper));
             }
             if (flags & 8388608 /* IndexedAccess */) {
-                return getIndexedAccessType(instantiateType(type.objectType, mapper), instantiateType(type.indexType, mapper), type.noUncheckedIndexedAccessCandidate, /*accessNode*/ undefined, type.aliasSymbol, instantiateTypes(type.aliasTypeArguments, mapper));
+                var newAliasSymbol = aliasSymbol || type.aliasSymbol;
+                var newAliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(type.aliasTypeArguments, mapper);
+                return getIndexedAccessType(instantiateType(type.objectType, mapper), instantiateType(type.indexType, mapper), type.noUncheckedIndexedAccessCandidate, /*accessNode*/ undefined, newAliasSymbol, newAliasTypeArguments);
             }
             if (flags & 16777216 /* Conditional */) {
-                return getConditionalTypeInstantiation(type, combineTypeMappers(type.mapper, mapper));
+                return getConditionalTypeInstantiation(type, combineTypeMappers(type.mapper, mapper), aliasSymbol, aliasTypeArguments);
             }
             if (flags & 33554432 /* Substitution */) {
                 var maybeVariable = instantiateType(type.baseType, mapper);
@@ -63436,6 +63451,11 @@ var ts;
             }
             return changed ? mappedTypes && getUnionType(mappedTypes, noReductions ? 0 /* None */ : 1 /* Literal */) : type;
         }
+        function mapTypeWithAlias(type, mapper, aliasSymbol, aliasTypeArguments) {
+            return type.flags & 1048576 /* Union */ && aliasSymbol ?
+                getUnionType(ts.map(type.types, mapper), 1 /* Literal */, aliasSymbol, aliasTypeArguments) :
+                mapType(type, mapper);
+        }
         function getConstituentCount(type) {
             return type.flags & 3145728 /* UnionOrIntersection */ ? type.types.length : 1;
         }
@@ -63582,10 +63602,15 @@ var ts;
                         return getExplicitThisType(node);
                     case 105 /* SuperKeyword */:
                         return checkSuperExpression(node);
-                    case 201 /* PropertyAccessExpression */:
+                    case 201 /* PropertyAccessExpression */: {
                         var type = getTypeOfDottedName(node.expression, diagnostic);
-                        var prop = type && getPropertyOfType(type, node.name.escapedText);
-                        return prop && getExplicitTypeOfSymbol(prop, diagnostic);
+                        if (type) {
+                            var name = node.name;
+                            var prop = getPropertyOfType(type, ts.isPrivateIdentifier(name) ? ts.getSymbolNameForPrivateIdentifier(type.symbol, name.escapedText) : name.escapedText);
+                            return prop && getExplicitTypeOfSymbol(prop, diagnostic);
+                        }
+                        return undefined;
+                    }
                     case 207 /* ParenthesizedExpression */:
                         return getTypeOfDottedName(node.expression, diagnostic);
                 }
@@ -71250,14 +71275,33 @@ var ts;
             rightType = checkNonNullType(rightType, right);
             // TypeScript 1.0 spec (April 2014): 4.15.5
             // The in operator requires the left operand to be of type Any, the String primitive type, or the Number primitive type,
-            // and the right operand to be of type Any, an object type, or a type parameter type.
+            // and the right operand to be
+            //
+            //   1. assignable to the non-primitive type,
+            //   2. an unconstrained type parameter,
+            //   3. a union or intersection including one or more type parameters, whose constituents are all assignable to the
+            //      the non-primitive type, or are unconstrainted type parameters, or have constraints assignable to the
+            //      non-primitive type, or
+            //   4. a type parameter whose constraint is
+            //      i. an object type,
+            //     ii. the non-primitive type, or
+            //    iii. a union or intersection with at least one constituent assignable to an object or non-primitive type.
+            //
+            // The divergent behavior for type parameters and unions containing type parameters is a workaround for type
+            // parameters not being narrowable. If the right operand is a concrete type, we can error if there is any chance
+            // it is a primitive. But if the operand is a type parameter, it cannot be narrowed, so we don't issue an error
+            // unless *all* instantiations would result in an error.
+            //
             // The result is always of the Boolean primitive type.
             if (!(allTypesAssignableToKind(leftType, 402653316 /* StringLike */ | 296 /* NumberLike */ | 12288 /* ESSymbolLike */) ||
                 isTypeAssignableToKind(leftType, 4194304 /* Index */ | 134217728 /* TemplateLiteral */ | 268435456 /* StringMapping */ | 262144 /* TypeParameter */))) {
                 error(left, ts.Diagnostics.The_left_hand_side_of_an_in_expression_must_be_of_type_any_string_number_or_symbol);
             }
-            if (!allTypesAssignableToKind(rightType, 67108864 /* NonPrimitive */ | 58982400 /* InstantiableNonPrimitive */)) {
-                error(right, ts.Diagnostics.The_right_hand_side_of_an_in_expression_must_be_of_type_any_an_object_type_or_a_type_parameter);
+            var rightTypeConstraint = getConstraintOfType(rightType);
+            if (!allTypesAssignableToKind(rightType, 67108864 /* NonPrimitive */ | 58982400 /* InstantiableNonPrimitive */) ||
+                rightTypeConstraint && (isTypeAssignableToKind(rightType, 3145728 /* UnionOrIntersection */) && !allTypesAssignableToKind(rightTypeConstraint, 67108864 /* NonPrimitive */ | 58982400 /* InstantiableNonPrimitive */) ||
+                    !maybeTypeOfKind(rightTypeConstraint, 67108864 /* NonPrimitive */ | 58982400 /* InstantiableNonPrimitive */ | 524288 /* Object */))) {
+                error(right, ts.Diagnostics.The_right_hand_side_of_an_in_expression_must_not_be_a_primitive);
             }
             return booleanType;
         }

lib/tsserverlibrary.js

@@ -8173,7 +8173,7 @@ var ts;
         The_left_hand_side_of_an_instanceof_expression_must_be_of_type_any_an_object_type_or_a_type_parameter: diag(2358, ts.DiagnosticCategory.Error, "The_left_hand_side_of_an_instanceof_expression_must_be_of_type_any_an_object_type_or_a_type_paramete_2358", "The left-hand side of an 'instanceof' expression must be of type 'any', an object type or a type parameter."),
         The_right_hand_side_of_an_instanceof_expression_must_be_of_type_any_or_of_a_type_assignable_to_the_Function_interface_type: diag(2359, ts.DiagnosticCategory.Error, "The_right_hand_side_of_an_instanceof_expression_must_be_of_type_any_or_of_a_type_assignable_to_the_F_2359", "The right-hand side of an 'instanceof' expression must be of type 'any' or of a type assignable to the 'Function' interface type."),
         The_left_hand_side_of_an_in_expression_must_be_of_type_any_string_number_or_symbol: diag(2360, ts.DiagnosticCategory.Error, "The_left_hand_side_of_an_in_expression_must_be_of_type_any_string_number_or_symbol_2360", "The left-hand side of an 'in' expression must be of type 'any', 'string', 'number', or 'symbol'."),
-        The_right_hand_side_of_an_in_expression_must_be_of_type_any_an_object_type_or_a_type_parameter: diag(2361, ts.DiagnosticCategory.Error, "The_right_hand_side_of_an_in_expression_must_be_of_type_any_an_object_type_or_a_type_parameter_2361", "The right-hand side of an 'in' expression must be of type 'any', an object type or a type parameter."),
+        The_right_hand_side_of_an_in_expression_must_not_be_a_primitive: diag(2361, ts.DiagnosticCategory.Error, "The_right_hand_side_of_an_in_expression_must_not_be_a_primitive_2361", "The right-hand side of an 'in' expression must not be a primitive."),
         The_left_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_bigint_or_an_enum_type: diag(2362, ts.DiagnosticCategory.Error, "The_left_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_bigint_or_an_enum_type_2362", "The left-hand side of an arithmetic operation must be of type 'any', 'number', 'bigint' or an enum type."),
         The_right_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_bigint_or_an_enum_type: diag(2363, ts.DiagnosticCategory.Error, "The_right_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_bigint_or_an_enum_type_2363", "The right-hand side of an arithmetic operation must be of type 'any', 'number', 'bigint' or an enum type."),
         The_left_hand_side_of_an_assignment_expression_must_be_a_variable_or_a_property_access: diag(2364, ts.DiagnosticCategory.Error, "The_left_hand_side_of_an_assignment_expression_must_be_a_variable_or_a_property_access_2364", "The left-hand side of an assignment expression must be a variable or a property access."),
@@ -54880,15 +54880,18 @@ var ts;
             type.resolvedTypeArguments = source.resolvedTypeArguments;
             return type;
         }
-        function createDeferredTypeReference(target, node, mapper) {
-            var aliasSymbol = getAliasSymbolForTypeNode(node);
-            var aliasTypeArguments = getTypeArgumentsForAliasSymbol(aliasSymbol);
+        function createDeferredTypeReference(target, node, mapper, aliasSymbol, aliasTypeArguments) {
+            if (!aliasSymbol) {
+                aliasSymbol = getAliasSymbolForTypeNode(node);
+                var localAliasTypeArguments = getTypeArgumentsForAliasSymbol(aliasSymbol);
+                aliasTypeArguments = mapper ? instantiateTypes(localAliasTypeArguments, mapper) : localAliasTypeArguments;
+            }
             var type = createObjectType(4 /* Reference */, target.symbol);
             type.target = target;
             type.node = node;
             type.mapper = mapper;
             type.aliasSymbol = aliasSymbol;
-            type.aliasTypeArguments = mapper ? instantiateTypes(aliasTypeArguments, mapper) : aliasTypeArguments;
+            type.aliasTypeArguments = aliasTypeArguments;
             return type;
         }
         function getTypeArguments(type) {
@@ -54953,17 +54956,17 @@ var ts;
             }
             return checkNoTypeArguments(node, symbol) ? type : errorType;
         }
-        function getTypeAliasInstantiation(symbol, typeArguments) {
+        function getTypeAliasInstantiation(symbol, typeArguments, aliasSymbol, aliasTypeArguments) {
             var type = getDeclaredTypeOfSymbol(symbol);
             if (type === intrinsicMarkerType && intrinsicTypeKinds.has(symbol.escapedName) && typeArguments && typeArguments.length === 1) {
                 return getStringMappingType(symbol, typeArguments[0]);
             }
             var links = getSymbolLinks(symbol);
             var typeParameters = links.typeParameters;
-            var id = getTypeListId(typeArguments);
+            var id = getTypeListId(typeArguments) + (aliasSymbol ? "@" + getSymbolId(aliasSymbol) : "");
             var instantiation = links.instantiations.get(id);
             if (!instantiation) {
-                links.instantiations.set(id, instantiation = instantiateType(type, createTypeMapper(typeParameters, fillMissingTypeArguments(typeArguments, typeParameters, getMinTypeArgumentCount(typeParameters), ts.isInJSFile(symbol.valueDeclaration)))));
+                links.instantiations.set(id, instantiation = instantiateTypeWithAlias(type, createTypeMapper(typeParameters, fillMissingTypeArguments(typeArguments, typeParameters, getMinTypeArgumentCount(typeParameters), ts.isInJSFile(symbol.valueDeclaration))), aliasSymbol, aliasTypeArguments));
             }
             return instantiation;
         }
@@ -54984,7 +54987,8 @@ var ts;
                         ts.Diagnostics.Generic_type_0_requires_between_1_and_2_type_arguments, symbolToString(symbol), minTypeArgumentCount, typeParameters.length);
                     return errorType;
                 }
-                return getTypeAliasInstantiation(symbol, typeArgumentsFromTypeReferenceNode(node));
+                var aliasSymbol = getAliasSymbolForTypeNode(node);
+                return getTypeAliasInstantiation(symbol, typeArgumentsFromTypeReferenceNode(node), aliasSymbol, getTypeArgumentsForAliasSymbol(aliasSymbol));
             }
             return checkNoTypeArguments(node, symbol) ? type : errorType;
         }
@@ -56086,7 +56090,7 @@ var ts;
             var result = createType(2097152 /* Intersection */);
             result.objectFlags = getPropagatingFlagsOfTypes(types, /*excludeKinds*/ 98304 /* Nullable */);
             result.types = types;
-            result.aliasSymbol = aliasSymbol; // See comment in `getUnionTypeFromSortedList`.
+            result.aliasSymbol = aliasSymbol;
             result.aliasTypeArguments = aliasTypeArguments;
             return result;
         }
@@ -56928,7 +56932,7 @@ var ts;
             }
             return type;
         }
-        function getConditionalType(root, mapper) {
+        function getConditionalType(root, mapper, aliasSymbol, aliasTypeArguments) {
             var result;
             var extraTypes;
             // We loop here for an immediately nested conditional type in the false position, effectively treating
@@ -56995,8 +56999,8 @@ var ts;
                 result.extendsType = extendsType;
                 result.mapper = mapper;
                 result.combinedMapper = combinedMapper;
-                result.aliasSymbol = root.aliasSymbol;
-                result.aliasTypeArguments = instantiateTypes(root.aliasTypeArguments, mapper); // TODO: GH#18217
+                result.aliasSymbol = aliasSymbol || root.aliasSymbol;
+                result.aliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(root.aliasTypeArguments, mapper); // TODO: GH#18217
                 break;
             }
             return extraTypes ? getUnionType(ts.append(extraTypes, result)) : result;
@@ -57712,7 +57716,7 @@ var ts;
             }
             return result;
         }
-        function getObjectTypeInstantiation(type, mapper) {
+        function getObjectTypeInstantiation(type, mapper, aliasSymbol, aliasTypeArguments) {
             var declaration = type.objectFlags & 4 /* Reference */ ? type.node : type.symbol.declarations[0];
             var links = getNodeLinks(declaration);
             var target = type.objectFlags & 4 /* Reference */ ? links.resolvedType :
@@ -57740,17 +57744,19 @@ var ts;
                 // instantiation cache key from the type IDs of the type arguments.
                 var combinedMapper_1 = combineTypeMappers(type.mapper, mapper);
                 var typeArguments = ts.map(typeParameters, function (t) { return getMappedType(t, combinedMapper_1); });
-                var id = getTypeListId(typeArguments);
+                var newAliasSymbol = aliasSymbol || type.aliasSymbol;
+                var id = getTypeListId(typeArguments) + (newAliasSymbol ? "@" + getSymbolId(newAliasSymbol) : "");
                 if (!target.instantiations) {
                     target.instantiations = new ts.Map();
-                    target.instantiations.set(getTypeListId(typeParameters), target);
+                    target.instantiations.set(getTypeListId(typeParameters) + (target.aliasSymbol ? "@" + getSymbolId(target.aliasSymbol) : ""), target);
                 }
                 var result = target.instantiations.get(id);
                 if (!result) {
                     var newMapper = createTypeMapper(typeParameters, typeArguments);
-                    result = target.objectFlags & 4 /* Reference */ ? createDeferredTypeReference(type.target, type.node, newMapper) :
-                        target.objectFlags & 32 /* Mapped */ ? instantiateMappedType(target, newMapper) :
-                            instantiateAnonymousType(target, newMapper);
+                    var newAliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(type.aliasTypeArguments, mapper);
+                    result = target.objectFlags & 4 /* Reference */ ? createDeferredTypeReference(type.target, type.node, newMapper, newAliasSymbol, newAliasTypeArguments) :
+                        target.objectFlags & 32 /* Mapped */ ? instantiateMappedType(target, newMapper, newAliasSymbol, newAliasTypeArguments) :
+                            instantiateAnonymousType(target, newMapper, newAliasSymbol, newAliasTypeArguments);
                     target.instantiations.set(id, result);
                 }
                 return result;
@@ -57799,7 +57805,7 @@ var ts;
             }
             return undefined;
         }
-        function instantiateMappedType(type, mapper) {
+        function instantiateMappedType(type, mapper, aliasSymbol, aliasTypeArguments) {
             // For a homomorphic mapped type { [P in keyof T]: X }, where T is some type variable, the mapping
             // operation depends on T as follows:
             // * If T is a primitive type no mapping is performed and the result is simply T.
@@ -57814,7 +57820,7 @@ var ts;
             if (typeVariable) {
                 var mappedTypeVariable = instantiateType(typeVariable, mapper);
                 if (typeVariable !== mappedTypeVariable) {
-                    return mapType(getReducedType(mappedTypeVariable), function (t) {
+                    return mapTypeWithAlias(getReducedType(mappedTypeVariable), function (t) {
                         if (t.flags & (3 /* AnyOrUnknown */ | 58982400 /* InstantiableNonPrimitive */ | 524288 /* Object */ | 2097152 /* Intersection */) && t !== wildcardType && t !== errorType) {
                             if (!type.declaration.nameType) {
                                 if (isArrayType(t)) {
@@ -57830,11 +57836,11 @@ var ts;
                             return instantiateAnonymousType(type, prependTypeMapping(typeVariable, t, mapper));
                         }
                         return t;
-                    });
+                    }, aliasSymbol, aliasTypeArguments);
                 }
             }
             // If the constraint type of the instantiation is the wildcard type, return the wildcard type.
-            return instantiateType(getConstraintTypeFromMappedType(type), mapper) === wildcardType ? wildcardType : instantiateAnonymousType(type, mapper);
+            return instantiateType(getConstraintTypeFromMappedType(type), mapper) === wildcardType ? wildcardType : instantiateAnonymousType(type, mapper, aliasSymbol, aliasTypeArguments);
         }
         function getModifiedReadonlyState(state, modifiers) {
             return modifiers & 1 /* IncludeReadonly */ ? true : modifiers & 2 /* ExcludeReadonly */ ? false : state;
@@ -57881,7 +57887,7 @@ var ts;
                 strictNullChecks && modifiers & 8 /* ExcludeOptional */ && isOptional ? getTypeWithFacts(propType, 524288 /* NEUndefined */) :
                     propType;
         }
-        function instantiateAnonymousType(type, mapper) {
+        function instantiateAnonymousType(type, mapper, aliasSymbol, aliasTypeArguments) {
             var result = createObjectType(type.objectFlags | 64 /* Instantiated */, type.symbol);
             if (type.objectFlags & 32 /* Mapped */) {
                 result.declaration = type.declaration;
@@ -57894,29 +57900,29 @@ var ts;
             }
             result.target = type;
             result.mapper = mapper;
-            result.aliasSymbol = type.aliasSymbol;
-            result.aliasTypeArguments = instantiateTypes(type.aliasTypeArguments, mapper);
+            result.aliasSymbol = aliasSymbol || type.aliasSymbol;
+            result.aliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(type.aliasTypeArguments, mapper);
             return result;
         }
-        function getConditionalTypeInstantiation(type, mapper) {
+        function getConditionalTypeInstantiation(type, mapper, aliasSymbol, aliasTypeArguments) {
             var root = type.root;
             if (root.outerTypeParameters) {
                 // We are instantiating a conditional type that has one or more type parameters in scope. Apply the
                 // mapper to the type parameters to produce the effective list of type arguments, and compute the
                 // instantiation cache key from the type IDs of the type arguments.
                 var typeArguments = ts.map(root.outerTypeParameters, function (t) { return getMappedType(t, mapper); });
-                var id = getTypeListId(typeArguments);
+                var id = getTypeListId(typeArguments) + (aliasSymbol ? "@" + getSymbolId(aliasSymbol) : "");
                 var result = root.instantiations.get(id);
                 if (!result) {
                     var newMapper = createTypeMapper(root.outerTypeParameters, typeArguments);
-                    result = instantiateConditionalType(root, newMapper);
+                    result = instantiateConditionalType(root, newMapper, aliasSymbol, aliasTypeArguments);
                     root.instantiations.set(id, result);
                 }
                 return result;
             }
             return type;
         }
-        function instantiateConditionalType(root, mapper) {
+        function instantiateConditionalType(root, mapper, aliasSymbol, aliasTypeArguments) {
             // Check if we have a conditional type where the check type is a naked type parameter. If so,
             // the conditional type is distributive over union types and when T is instantiated to a union
             // type A | B, we produce (A extends U ? X : Y) | (B extends U ? X : Y).
@@ -57924,13 +57930,16 @@ var ts;
                 var checkType_1 = root.checkType;
                 var instantiatedType = getMappedType(checkType_1, mapper);
                 if (checkType_1 !== instantiatedType && instantiatedType.flags & (1048576 /* Union */ | 131072 /* Never */)) {
-                    return mapType(instantiatedType, function (t) { return getConditionalType(root, prependTypeMapping(checkType_1, t, mapper)); });
+                    return mapTypeWithAlias(instantiatedType, function (t) { return getConditionalType(root, prependTypeMapping(checkType_1, t, mapper)); }, aliasSymbol, aliasTypeArguments);
                 }
             }
-            return getConditionalType(root, mapper);
+            return getConditionalType(root, mapper, aliasSymbol, aliasTypeArguments);
         }
         function instantiateType(type, mapper) {
-            if (!(type && mapper && couldContainTypeVariables(type))) {
+            return type && mapper ? instantiateTypeWithAlias(type, mapper, /*aliasSymbol*/ undefined, /*aliasTypeArguments*/ undefined) : type;
+        }
+        function instantiateTypeWithAlias(type, mapper, aliasSymbol, aliasTypeArguments) {
+            if (!couldContainTypeVariables(type)) {
                 return type;
             }
             if (instantiationDepth === 50 || instantiationCount >= 5000000) {
@@ -57944,11 +57953,11 @@ var ts;
             totalInstantiationCount++;
             instantiationCount++;
             instantiationDepth++;
-            var result = instantiateTypeWorker(type, mapper);
+            var result = instantiateTypeWorker(type, mapper, aliasSymbol, aliasTypeArguments);
             instantiationDepth--;
             return result;
         }
-        function instantiateTypeWorker(type, mapper) {
+        function instantiateTypeWorker(type, mapper, aliasSymbol, aliasTypeArguments) {
             var flags = type.flags;
             if (flags & 262144 /* TypeParameter */) {
                 return getMappedType(type, mapper);
@@ -57956,12 +57965,12 @@ var ts;
             if (flags & 524288 /* Object */) {
                 var objectFlags = type.objectFlags;
                 if (objectFlags & (4 /* Reference */ | 16 /* Anonymous */ | 32 /* Mapped */)) {
-                    if (objectFlags & 4 /* Reference */ && !(type.node)) {
+                    if (objectFlags & 4 /* Reference */ && !type.node) {
                         var resolvedTypeArguments = type.resolvedTypeArguments;
                         var newTypeArguments = instantiateTypes(resolvedTypeArguments, mapper);
                         return newTypeArguments !== resolvedTypeArguments ? createNormalizedTypeReference(type.target, newTypeArguments) : type;
                     }
-                    return getObjectTypeInstantiation(type, mapper);
+                    return getObjectTypeInstantiation(type, mapper, aliasSymbol, aliasTypeArguments);
                 }
                 return type;
             }
@@ -57969,10 +57978,14 @@ var ts;
                 var origin = type.flags & 1048576 /* Union */ ? type.origin : undefined;
                 var types = origin && origin.flags & 3145728 /* UnionOrIntersection */ ? origin.types : type.types;
                 var newTypes = instantiateTypes(types, mapper);
-                return newTypes === types ? type :
-                    flags & 2097152 /* Intersection */ || origin && origin.flags & 2097152 /* Intersection */ ?
-                        getIntersectionType(newTypes, type.aliasSymbol, instantiateTypes(type.aliasTypeArguments, mapper)) :
-                        getUnionType(newTypes, 1 /* Literal */, type.aliasSymbol, instantiateTypes(type.aliasTypeArguments, mapper));
+                if (newTypes === types && aliasSymbol === type.aliasSymbol) {
+                    return type;
+                }
+                var newAliasSymbol = aliasSymbol || type.aliasSymbol;
+                var newAliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(type.aliasTypeArguments, mapper);
+                return flags & 2097152 /* Intersection */ || origin && origin.flags & 2097152 /* Intersection */ ?
+                    getIntersectionType(newTypes, newAliasSymbol, newAliasTypeArguments) :
+                    getUnionType(newTypes, 1 /* Literal */, newAliasSymbol, newAliasTypeArguments);
             }
             if (flags & 4194304 /* Index */) {
                 return getIndexType(instantiateType(type.type, mapper));
@@ -57984,10 +57997,12 @@ var ts;
                 return getStringMappingType(type.symbol, instantiateType(type.type, mapper));
             }
             if (flags & 8388608 /* IndexedAccess */) {
-                return getIndexedAccessType(instantiateType(type.objectType, mapper), instantiateType(type.indexType, mapper), type.noUncheckedIndexedAccessCandidate, /*accessNode*/ undefined, type.aliasSymbol, instantiateTypes(type.aliasTypeArguments, mapper));
+                var newAliasSymbol = aliasSymbol || type.aliasSymbol;
+                var newAliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(type.aliasTypeArguments, mapper);
+                return getIndexedAccessType(instantiateType(type.objectType, mapper), instantiateType(type.indexType, mapper), type.noUncheckedIndexedAccessCandidate, /*accessNode*/ undefined, newAliasSymbol, newAliasTypeArguments);
             }
             if (flags & 16777216 /* Conditional */) {
-                return getConditionalTypeInstantiation(type, combineTypeMappers(type.mapper, mapper));
+                return getConditionalTypeInstantiation(type, combineTypeMappers(type.mapper, mapper), aliasSymbol, aliasTypeArguments);
             }
             if (flags & 33554432 /* Substitution */) {
                 var maybeVariable = instantiateType(type.baseType, mapper);
@@ -63630,6 +63645,11 @@ var ts;
             }
             return changed ? mappedTypes && getUnionType(mappedTypes, noReductions ? 0 /* None */ : 1 /* Literal */) : type;
         }
+        function mapTypeWithAlias(type, mapper, aliasSymbol, aliasTypeArguments) {
+            return type.flags & 1048576 /* Union */ && aliasSymbol ?
+                getUnionType(ts.map(type.types, mapper), 1 /* Literal */, aliasSymbol, aliasTypeArguments) :
+                mapType(type, mapper);
+        }
         function getConstituentCount(type) {
             return type.flags & 3145728 /* UnionOrIntersection */ ? type.types.length : 1;
         }
@@ -63776,10 +63796,15 @@ var ts;
                         return getExplicitThisType(node);
                     case 105 /* SuperKeyword */:
                         return checkSuperExpression(node);
-                    case 201 /* PropertyAccessExpression */:
+                    case 201 /* PropertyAccessExpression */: {
                         var type = getTypeOfDottedName(node.expression, diagnostic);
-                        var prop = type && getPropertyOfType(type, node.name.escapedText);
-                        return prop && getExplicitTypeOfSymbol(prop, diagnostic);
+                        if (type) {
+                            var name = node.name;
+                            var prop = getPropertyOfType(type, ts.isPrivateIdentifier(name) ? ts.getSymbolNameForPrivateIdentifier(type.symbol, name.escapedText) : name.escapedText);
+                            return prop && getExplicitTypeOfSymbol(prop, diagnostic);
+                        }
+                        return undefined;
+                    }
                     case 207 /* ParenthesizedExpression */:
                         return getTypeOfDottedName(node.expression, diagnostic);
                 }
@@ -71444,14 +71469,33 @@ var ts;
             rightType = checkNonNullType(rightType, right);
             // TypeScript 1.0 spec (April 2014): 4.15.5
             // The in operator requires the left operand to be of type Any, the String primitive type, or the Number primitive type,
-            // and the right operand to be of type Any, an object type, or a type parameter type.
+            // and the right operand to be
+            //
+            //   1. assignable to the non-primitive type,
+            //   2. an unconstrained type parameter,
+            //   3. a union or intersection including one or more type parameters, whose constituents are all assignable to the
+            //      the non-primitive type, or are unconstrainted type parameters, or have constraints assignable to the
+            //      non-primitive type, or
+            //   4. a type parameter whose constraint is
+            //      i. an object type,
+            //     ii. the non-primitive type, or
+            //    iii. a union or intersection with at least one constituent assignable to an object or non-primitive type.
+            //
+            // The divergent behavior for type parameters and unions containing type parameters is a workaround for type
+            // parameters not being narrowable. If the right operand is a concrete type, we can error if there is any chance
+            // it is a primitive. But if the operand is a type parameter, it cannot be narrowed, so we don't issue an error
+            // unless *all* instantiations would result in an error.
+            //
             // The result is always of the Boolean primitive type.
             if (!(allTypesAssignableToKind(leftType, 402653316 /* StringLike */ | 296 /* NumberLike */ | 12288 /* ESSymbolLike */) ||
                 isTypeAssignableToKind(leftType, 4194304 /* Index */ | 134217728 /* TemplateLiteral */ | 268435456 /* StringMapping */ | 262144 /* TypeParameter */))) {
                 error(left, ts.Diagnostics.The_left_hand_side_of_an_in_expression_must_be_of_type_any_string_number_or_symbol);
             }
-            if (!allTypesAssignableToKind(rightType, 67108864 /* NonPrimitive */ | 58982400 /* InstantiableNonPrimitive */)) {
-                error(right, ts.Diagnostics.The_right_hand_side_of_an_in_expression_must_be_of_type_any_an_object_type_or_a_type_parameter);
+            var rightTypeConstraint = getConstraintOfType(rightType);
+            if (!allTypesAssignableToKind(rightType, 67108864 /* NonPrimitive */ | 58982400 /* InstantiableNonPrimitive */) ||
+                rightTypeConstraint && (isTypeAssignableToKind(rightType, 3145728 /* UnionOrIntersection */) && !allTypesAssignableToKind(rightTypeConstraint, 67108864 /* NonPrimitive */ | 58982400 /* InstantiableNonPrimitive */) ||
+                    !maybeTypeOfKind(rightTypeConstraint, 67108864 /* NonPrimitive */ | 58982400 /* InstantiableNonPrimitive */ | 524288 /* Object */))) {
+                error(right, ts.Diagnostics.The_right_hand_side_of_an_in_expression_must_not_be_a_primitive);
             }
             return booleanType;
         }

lib/typescript.js

@@ -8173,7 +8173,7 @@ var ts;
         The_left_hand_side_of_an_instanceof_expression_must_be_of_type_any_an_object_type_or_a_type_parameter: diag(2358, ts.DiagnosticCategory.Error, "The_left_hand_side_of_an_instanceof_expression_must_be_of_type_any_an_object_type_or_a_type_paramete_2358", "The left-hand side of an 'instanceof' expression must be of type 'any', an object type or a type parameter."),
         The_right_hand_side_of_an_instanceof_expression_must_be_of_type_any_or_of_a_type_assignable_to_the_Function_interface_type: diag(2359, ts.DiagnosticCategory.Error, "The_right_hand_side_of_an_instanceof_expression_must_be_of_type_any_or_of_a_type_assignable_to_the_F_2359", "The right-hand side of an 'instanceof' expression must be of type 'any' or of a type assignable to the 'Function' interface type."),
         The_left_hand_side_of_an_in_expression_must_be_of_type_any_string_number_or_symbol: diag(2360, ts.DiagnosticCategory.Error, "The_left_hand_side_of_an_in_expression_must_be_of_type_any_string_number_or_symbol_2360", "The left-hand side of an 'in' expression must be of type 'any', 'string', 'number', or 'symbol'."),
-        The_right_hand_side_of_an_in_expression_must_be_of_type_any_an_object_type_or_a_type_parameter: diag(2361, ts.DiagnosticCategory.Error, "The_right_hand_side_of_an_in_expression_must_be_of_type_any_an_object_type_or_a_type_parameter_2361", "The right-hand side of an 'in' expression must be of type 'any', an object type or a type parameter."),
+        The_right_hand_side_of_an_in_expression_must_not_be_a_primitive: diag(2361, ts.DiagnosticCategory.Error, "The_right_hand_side_of_an_in_expression_must_not_be_a_primitive_2361", "The right-hand side of an 'in' expression must not be a primitive."),
         The_left_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_bigint_or_an_enum_type: diag(2362, ts.DiagnosticCategory.Error, "The_left_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_bigint_or_an_enum_type_2362", "The left-hand side of an arithmetic operation must be of type 'any', 'number', 'bigint' or an enum type."),
         The_right_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_bigint_or_an_enum_type: diag(2363, ts.DiagnosticCategory.Error, "The_right_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_bigint_or_an_enum_type_2363", "The right-hand side of an arithmetic operation must be of type 'any', 'number', 'bigint' or an enum type."),
         The_left_hand_side_of_an_assignment_expression_must_be_a_variable_or_a_property_access: diag(2364, ts.DiagnosticCategory.Error, "The_left_hand_side_of_an_assignment_expression_must_be_a_variable_or_a_property_access_2364", "The left-hand side of an assignment expression must be a variable or a property access."),
@@ -54880,15 +54880,18 @@ var ts;
             type.resolvedTypeArguments = source.resolvedTypeArguments;
             return type;
         }
-        function createDeferredTypeReference(target, node, mapper) {
-            var aliasSymbol = getAliasSymbolForTypeNode(node);
-            var aliasTypeArguments = getTypeArgumentsForAliasSymbol(aliasSymbol);
+        function createDeferredTypeReference(target, node, mapper, aliasSymbol, aliasTypeArguments) {
+            if (!aliasSymbol) {
+                aliasSymbol = getAliasSymbolForTypeNode(node);
+                var localAliasTypeArguments = getTypeArgumentsForAliasSymbol(aliasSymbol);
+                aliasTypeArguments = mapper ? instantiateTypes(localAliasTypeArguments, mapper) : localAliasTypeArguments;
+            }
             var type = createObjectType(4 /* Reference */, target.symbol);
             type.target = target;
             type.node = node;
             type.mapper = mapper;
             type.aliasSymbol = aliasSymbol;
-            type.aliasTypeArguments = mapper ? instantiateTypes(aliasTypeArguments, mapper) : aliasTypeArguments;
+            type.aliasTypeArguments = aliasTypeArguments;
             return type;
         }
         function getTypeArguments(type) {
@@ -54953,17 +54956,17 @@ var ts;
             }
             return checkNoTypeArguments(node, symbol) ? type : errorType;
         }
-        function getTypeAliasInstantiation(symbol, typeArguments) {
+        function getTypeAliasInstantiation(symbol, typeArguments, aliasSymbol, aliasTypeArguments) {
             var type = getDeclaredTypeOfSymbol(symbol);
             if (type === intrinsicMarkerType && intrinsicTypeKinds.has(symbol.escapedName) && typeArguments && typeArguments.length === 1) {
                 return getStringMappingType(symbol, typeArguments[0]);
             }
             var links = getSymbolLinks(symbol);
             var typeParameters = links.typeParameters;
-            var id = getTypeListId(typeArguments);
+            var id = getTypeListId(typeArguments) + (aliasSymbol ? "@" + getSymbolId(aliasSymbol) : "");
             var instantiation = links.instantiations.get(id);
             if (!instantiation) {
-                links.instantiations.set(id, instantiation = instantiateType(type, createTypeMapper(typeParameters, fillMissingTypeArguments(typeArguments, typeParameters, getMinTypeArgumentCount(typeParameters), ts.isInJSFile(symbol.valueDeclaration)))));
+                links.instantiations.set(id, instantiation = instantiateTypeWithAlias(type, createTypeMapper(typeParameters, fillMissingTypeArguments(typeArguments, typeParameters, getMinTypeArgumentCount(typeParameters), ts.isInJSFile(symbol.valueDeclaration))), aliasSymbol, aliasTypeArguments));
             }
             return instantiation;
         }
@@ -54984,7 +54987,8 @@ var ts;
                         ts.Diagnostics.Generic_type_0_requires_between_1_and_2_type_arguments, symbolToString(symbol), minTypeArgumentCount, typeParameters.length);
                     return errorType;
                 }
-                return getTypeAliasInstantiation(symbol, typeArgumentsFromTypeReferenceNode(node));
+                var aliasSymbol = getAliasSymbolForTypeNode(node);
+                return getTypeAliasInstantiation(symbol, typeArgumentsFromTypeReferenceNode(node), aliasSymbol, getTypeArgumentsForAliasSymbol(aliasSymbol));
             }
             return checkNoTypeArguments(node, symbol) ? type : errorType;
         }
@@ -56086,7 +56090,7 @@ var ts;
             var result = createType(2097152 /* Intersection */);
             result.objectFlags = getPropagatingFlagsOfTypes(types, /*excludeKinds*/ 98304 /* Nullable */);
             result.types = types;
-            result.aliasSymbol = aliasSymbol; // See comment in `getUnionTypeFromSortedList`.
+            result.aliasSymbol = aliasSymbol;
             result.aliasTypeArguments = aliasTypeArguments;
             return result;
         }
@@ -56928,7 +56932,7 @@ var ts;
             }
             return type;
         }
-        function getConditionalType(root, mapper) {
+        function getConditionalType(root, mapper, aliasSymbol, aliasTypeArguments) {
             var result;
             var extraTypes;
             // We loop here for an immediately nested conditional type in the false position, effectively treating
@@ -56995,8 +56999,8 @@ var ts;
                 result.extendsType = extendsType;
                 result.mapper = mapper;
                 result.combinedMapper = combinedMapper;
-                result.aliasSymbol = root.aliasSymbol;
-                result.aliasTypeArguments = instantiateTypes(root.aliasTypeArguments, mapper); // TODO: GH#18217
+                result.aliasSymbol = aliasSymbol || root.aliasSymbol;
+                result.aliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(root.aliasTypeArguments, mapper); // TODO: GH#18217
                 break;
             }
             return extraTypes ? getUnionType(ts.append(extraTypes, result)) : result;
@@ -57712,7 +57716,7 @@ var ts;
             }
             return result;
         }
-        function getObjectTypeInstantiation(type, mapper) {
+        function getObjectTypeInstantiation(type, mapper, aliasSymbol, aliasTypeArguments) {
             var declaration = type.objectFlags & 4 /* Reference */ ? type.node : type.symbol.declarations[0];
             var links = getNodeLinks(declaration);
             var target = type.objectFlags & 4 /* Reference */ ? links.resolvedType :
@@ -57740,17 +57744,19 @@ var ts;
                 // instantiation cache key from the type IDs of the type arguments.
                 var combinedMapper_1 = combineTypeMappers(type.mapper, mapper);
                 var typeArguments = ts.map(typeParameters, function (t) { return getMappedType(t, combinedMapper_1); });
-                var id = getTypeListId(typeArguments);
+                var newAliasSymbol = aliasSymbol || type.aliasSymbol;
+                var id = getTypeListId(typeArguments) + (newAliasSymbol ? "@" + getSymbolId(newAliasSymbol) : "");
                 if (!target.instantiations) {
                     target.instantiations = new ts.Map();
-                    target.instantiations.set(getTypeListId(typeParameters), target);
+                    target.instantiations.set(getTypeListId(typeParameters) + (target.aliasSymbol ? "@" + getSymbolId(target.aliasSymbol) : ""), target);
                 }
                 var result = target.instantiations.get(id);
                 if (!result) {
                     var newMapper = createTypeMapper(typeParameters, typeArguments);
-                    result = target.objectFlags & 4 /* Reference */ ? createDeferredTypeReference(type.target, type.node, newMapper) :
-                        target.objectFlags & 32 /* Mapped */ ? instantiateMappedType(target, newMapper) :
-                            instantiateAnonymousType(target, newMapper);
+                    var newAliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(type.aliasTypeArguments, mapper);
+                    result = target.objectFlags & 4 /* Reference */ ? createDeferredTypeReference(type.target, type.node, newMapper, newAliasSymbol, newAliasTypeArguments) :
+                        target.objectFlags & 32 /* Mapped */ ? instantiateMappedType(target, newMapper, newAliasSymbol, newAliasTypeArguments) :
+                            instantiateAnonymousType(target, newMapper, newAliasSymbol, newAliasTypeArguments);
                     target.instantiations.set(id, result);
                 }
                 return result;
@@ -57799,7 +57805,7 @@ var ts;
             }
             return undefined;
         }
-        function instantiateMappedType(type, mapper) {
+        function instantiateMappedType(type, mapper, aliasSymbol, aliasTypeArguments) {
             // For a homomorphic mapped type { [P in keyof T]: X }, where T is some type variable, the mapping
             // operation depends on T as follows:
             // * If T is a primitive type no mapping is performed and the result is simply T.
@@ -57814,7 +57820,7 @@ var ts;
             if (typeVariable) {
                 var mappedTypeVariable = instantiateType(typeVariable, mapper);
                 if (typeVariable !== mappedTypeVariable) {
-                    return mapType(getReducedType(mappedTypeVariable), function (t) {
+                    return mapTypeWithAlias(getReducedType(mappedTypeVariable), function (t) {
                         if (t.flags & (3 /* AnyOrUnknown */ | 58982400 /* InstantiableNonPrimitive */ | 524288 /* Object */ | 2097152 /* Intersection */) && t !== wildcardType && t !== errorType) {
                             if (!type.declaration.nameType) {
                                 if (isArrayType(t)) {
@@ -57830,11 +57836,11 @@ var ts;
                             return instantiateAnonymousType(type, prependTypeMapping(typeVariable, t, mapper));
                         }
                         return t;
-                    });
+                    }, aliasSymbol, aliasTypeArguments);
                 }
             }
             // If the constraint type of the instantiation is the wildcard type, return the wildcard type.
-            return instantiateType(getConstraintTypeFromMappedType(type), mapper) === wildcardType ? wildcardType : instantiateAnonymousType(type, mapper);
+            return instantiateType(getConstraintTypeFromMappedType(type), mapper) === wildcardType ? wildcardType : instantiateAnonymousType(type, mapper, aliasSymbol, aliasTypeArguments);
         }
         function getModifiedReadonlyState(state, modifiers) {
             return modifiers & 1 /* IncludeReadonly */ ? true : modifiers & 2 /* ExcludeReadonly */ ? false : state;
@@ -57881,7 +57887,7 @@ var ts;
                 strictNullChecks && modifiers & 8 /* ExcludeOptional */ && isOptional ? getTypeWithFacts(propType, 524288 /* NEUndefined */) :
                     propType;
         }
-        function instantiateAnonymousType(type, mapper) {
+        function instantiateAnonymousType(type, mapper, aliasSymbol, aliasTypeArguments) {
             var result = createObjectType(type.objectFlags | 64 /* Instantiated */, type.symbol);
             if (type.objectFlags & 32 /* Mapped */) {
                 result.declaration = type.declaration;
@@ -57894,29 +57900,29 @@ var ts;
             }
             result.target = type;
             result.mapper = mapper;
-            result.aliasSymbol = type.aliasSymbol;
-            result.aliasTypeArguments = instantiateTypes(type.aliasTypeArguments, mapper);
+            result.aliasSymbol = aliasSymbol || type.aliasSymbol;
+            result.aliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(type.aliasTypeArguments, mapper);
             return result;
         }
-        function getConditionalTypeInstantiation(type, mapper) {
+        function getConditionalTypeInstantiation(type, mapper, aliasSymbol, aliasTypeArguments) {
             var root = type.root;
             if (root.outerTypeParameters) {
                 // We are instantiating a conditional type that has one or more type parameters in scope. Apply the
                 // mapper to the type parameters to produce the effective list of type arguments, and compute the
                 // instantiation cache key from the type IDs of the type arguments.
                 var typeArguments = ts.map(root.outerTypeParameters, function (t) { return getMappedType(t, mapper); });
-                var id = getTypeListId(typeArguments);
+                var id = getTypeListId(typeArguments) + (aliasSymbol ? "@" + getSymbolId(aliasSymbol) : "");
                 var result = root.instantiations.get(id);
                 if (!result) {
                     var newMapper = createTypeMapper(root.outerTypeParameters, typeArguments);
-                    result = instantiateConditionalType(root, newMapper);
+                    result = instantiateConditionalType(root, newMapper, aliasSymbol, aliasTypeArguments);
                     root.instantiations.set(id, result);
                 }
                 return result;
             }
             return type;
         }
-        function instantiateConditionalType(root, mapper) {
+        function instantiateConditionalType(root, mapper, aliasSymbol, aliasTypeArguments) {
             // Check if we have a conditional type where the check type is a naked type parameter. If so,
             // the conditional type is distributive over union types and when T is instantiated to a union
             // type A | B, we produce (A extends U ? X : Y) | (B extends U ? X : Y).
@@ -57924,13 +57930,16 @@ var ts;
                 var checkType_1 = root.checkType;
                 var instantiatedType = getMappedType(checkType_1, mapper);
                 if (checkType_1 !== instantiatedType && instantiatedType.flags & (1048576 /* Union */ | 131072 /* Never */)) {
-                    return mapType(instantiatedType, function (t) { return getConditionalType(root, prependTypeMapping(checkType_1, t, mapper)); });
+                    return mapTypeWithAlias(instantiatedType, function (t) { return getConditionalType(root, prependTypeMapping(checkType_1, t, mapper)); }, aliasSymbol, aliasTypeArguments);
                 }
             }
-            return getConditionalType(root, mapper);
+            return getConditionalType(root, mapper, aliasSymbol, aliasTypeArguments);
         }
         function instantiateType(type, mapper) {
-            if (!(type && mapper && couldContainTypeVariables(type))) {
+            return type && mapper ? instantiateTypeWithAlias(type, mapper, /*aliasSymbol*/ undefined, /*aliasTypeArguments*/ undefined) : type;
+        }
+        function instantiateTypeWithAlias(type, mapper, aliasSymbol, aliasTypeArguments) {
+            if (!couldContainTypeVariables(type)) {
                 return type;
             }
             if (instantiationDepth === 50 || instantiationCount >= 5000000) {
@@ -57944,11 +57953,11 @@ var ts;
             totalInstantiationCount++;
             instantiationCount++;
             instantiationDepth++;
-            var result = instantiateTypeWorker(type, mapper);
+            var result = instantiateTypeWorker(type, mapper, aliasSymbol, aliasTypeArguments);
             instantiationDepth--;
             return result;
         }
-        function instantiateTypeWorker(type, mapper) {
+        function instantiateTypeWorker(type, mapper, aliasSymbol, aliasTypeArguments) {
             var flags = type.flags;
             if (flags & 262144 /* TypeParameter */) {
                 return getMappedType(type, mapper);
@@ -57956,12 +57965,12 @@ var ts;
             if (flags & 524288 /* Object */) {
                 var objectFlags = type.objectFlags;
                 if (objectFlags & (4 /* Reference */ | 16 /* Anonymous */ | 32 /* Mapped */)) {
-                    if (objectFlags & 4 /* Reference */ && !(type.node)) {
+                    if (objectFlags & 4 /* Reference */ && !type.node) {
                         var resolvedTypeArguments = type.resolvedTypeArguments;
                         var newTypeArguments = instantiateTypes(resolvedTypeArguments, mapper);
                         return newTypeArguments !== resolvedTypeArguments ? createNormalizedTypeReference(type.target, newTypeArguments) : type;
                     }
-                    return getObjectTypeInstantiation(type, mapper);
+                    return getObjectTypeInstantiation(type, mapper, aliasSymbol, aliasTypeArguments);
                 }
                 return type;
             }
@@ -57969,10 +57978,14 @@ var ts;
                 var origin = type.flags & 1048576 /* Union */ ? type.origin : undefined;
                 var types = origin && origin.flags & 3145728 /* UnionOrIntersection */ ? origin.types : type.types;
                 var newTypes = instantiateTypes(types, mapper);
-                return newTypes === types ? type :
-                    flags & 2097152 /* Intersection */ || origin && origin.flags & 2097152 /* Intersection */ ?
-                        getIntersectionType(newTypes, type.aliasSymbol, instantiateTypes(type.aliasTypeArguments, mapper)) :
-                        getUnionType(newTypes, 1 /* Literal */, type.aliasSymbol, instantiateTypes(type.aliasTypeArguments, mapper));
+                if (newTypes === types && aliasSymbol === type.aliasSymbol) {
+                    return type;
+                }
+                var newAliasSymbol = aliasSymbol || type.aliasSymbol;
+                var newAliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(type.aliasTypeArguments, mapper);
+                return flags & 2097152 /* Intersection */ || origin && origin.flags & 2097152 /* Intersection */ ?
+                    getIntersectionType(newTypes, newAliasSymbol, newAliasTypeArguments) :
+                    getUnionType(newTypes, 1 /* Literal */, newAliasSymbol, newAliasTypeArguments);
             }
             if (flags & 4194304 /* Index */) {
                 return getIndexType(instantiateType(type.type, mapper));
@@ -57984,10 +57997,12 @@ var ts;
                 return getStringMappingType(type.symbol, instantiateType(type.type, mapper));
             }
             if (flags & 8388608 /* IndexedAccess */) {
-                return getIndexedAccessType(instantiateType(type.objectType, mapper), instantiateType(type.indexType, mapper), type.noUncheckedIndexedAccessCandidate, /*accessNode*/ undefined, type.aliasSymbol, instantiateTypes(type.aliasTypeArguments, mapper));
+                var newAliasSymbol = aliasSymbol || type.aliasSymbol;
+                var newAliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(type.aliasTypeArguments, mapper);
+                return getIndexedAccessType(instantiateType(type.objectType, mapper), instantiateType(type.indexType, mapper), type.noUncheckedIndexedAccessCandidate, /*accessNode*/ undefined, newAliasSymbol, newAliasTypeArguments);
             }
             if (flags & 16777216 /* Conditional */) {
-                return getConditionalTypeInstantiation(type, combineTypeMappers(type.mapper, mapper));
+                return getConditionalTypeInstantiation(type, combineTypeMappers(type.mapper, mapper), aliasSymbol, aliasTypeArguments);
             }
             if (flags & 33554432 /* Substitution */) {
                 var maybeVariable = instantiateType(type.baseType, mapper);
@@ -63630,6 +63645,11 @@ var ts;
             }
             return changed ? mappedTypes && getUnionType(mappedTypes, noReductions ? 0 /* None */ : 1 /* Literal */) : type;
         }
+        function mapTypeWithAlias(type, mapper, aliasSymbol, aliasTypeArguments) {
+            return type.flags & 1048576 /* Union */ && aliasSymbol ?
+                getUnionType(ts.map(type.types, mapper), 1 /* Literal */, aliasSymbol, aliasTypeArguments) :
+                mapType(type, mapper);
+        }
         function getConstituentCount(type) {
             return type.flags & 3145728 /* UnionOrIntersection */ ? type.types.length : 1;
         }
@@ -63776,10 +63796,15 @@ var ts;
                         return getExplicitThisType(node);
                     case 105 /* SuperKeyword */:
                         return checkSuperExpression(node);
-                    case 201 /* PropertyAccessExpression */:
+                    case 201 /* PropertyAccessExpression */: {
                         var type = getTypeOfDottedName(node.expression, diagnostic);
-                        var prop = type && getPropertyOfType(type, node.name.escapedText);
-                        return prop && getExplicitTypeOfSymbol(prop, diagnostic);
+                        if (type) {
+                            var name = node.name;
+                            var prop = getPropertyOfType(type, ts.isPrivateIdentifier(name) ? ts.getSymbolNameForPrivateIdentifier(type.symbol, name.escapedText) : name.escapedText);
+                            return prop && getExplicitTypeOfSymbol(prop, diagnostic);
+                        }
+                        return undefined;
+                    }
                     case 207 /* ParenthesizedExpression */:
                         return getTypeOfDottedName(node.expression, diagnostic);
                 }
@@ -71444,14 +71469,33 @@ var ts;
             rightType = checkNonNullType(rightType, right);
             // TypeScript 1.0 spec (April 2014): 4.15.5
             // The in operator requires the left operand to be of type Any, the String primitive type, or the Number primitive type,
-            // and the right operand to be of type Any, an object type, or a type parameter type.
+            // and the right operand to be
+            //
+            //   1. assignable to the non-primitive type,
+            //   2. an unconstrained type parameter,
+            //   3. a union or intersection including one or more type parameters, whose constituents are all assignable to the
+            //      the non-primitive type, or are unconstrainted type parameters, or have constraints assignable to the
+            //      non-primitive type, or
+            //   4. a type parameter whose constraint is
+            //      i. an object type,
+            //     ii. the non-primitive type, or
+            //    iii. a union or intersection with at least one constituent assignable to an object or non-primitive type.
+            //
+            // The divergent behavior for type parameters and unions containing type parameters is a workaround for type
+            // parameters not being narrowable. If the right operand is a concrete type, we can error if there is any chance
+            // it is a primitive. But if the operand is a type parameter, it cannot be narrowed, so we don't issue an error
+            // unless *all* instantiations would result in an error.
+            //
             // The result is always of the Boolean primitive type.
             if (!(allTypesAssignableToKind(leftType, 402653316 /* StringLike */ | 296 /* NumberLike */ | 12288 /* ESSymbolLike */) ||
                 isTypeAssignableToKind(leftType, 4194304 /* Index */ | 134217728 /* TemplateLiteral */ | 268435456 /* StringMapping */ | 262144 /* TypeParameter */))) {
                 error(left, ts.Diagnostics.The_left_hand_side_of_an_in_expression_must_be_of_type_any_string_number_or_symbol);
             }
-            if (!allTypesAssignableToKind(rightType, 67108864 /* NonPrimitive */ | 58982400 /* InstantiableNonPrimitive */)) {
-                error(right, ts.Diagnostics.The_right_hand_side_of_an_in_expression_must_be_of_type_any_an_object_type_or_a_type_parameter);
+            var rightTypeConstraint = getConstraintOfType(rightType);
+            if (!allTypesAssignableToKind(rightType, 67108864 /* NonPrimitive */ | 58982400 /* InstantiableNonPrimitive */) ||
+                rightTypeConstraint && (isTypeAssignableToKind(rightType, 3145728 /* UnionOrIntersection */) && !allTypesAssignableToKind(rightTypeConstraint, 67108864 /* NonPrimitive */ | 58982400 /* InstantiableNonPrimitive */) ||
+                    !maybeTypeOfKind(rightTypeConstraint, 67108864 /* NonPrimitive */ | 58982400 /* InstantiableNonPrimitive */ | 524288 /* Object */))) {
+                error(right, ts.Diagnostics.The_right_hand_side_of_an_in_expression_must_not_be_a_primitive);
             }
             return booleanType;
         }

lib/typescriptServices.js

@@ -8173,7 +8173,7 @@ var ts;
         The_left_hand_side_of_an_instanceof_expression_must_be_of_type_any_an_object_type_or_a_type_parameter: diag(2358, ts.DiagnosticCategory.Error, "The_left_hand_side_of_an_instanceof_expression_must_be_of_type_any_an_object_type_or_a_type_paramete_2358", "The left-hand side of an 'instanceof' expression must be of type 'any', an object type or a type parameter."),
         The_right_hand_side_of_an_instanceof_expression_must_be_of_type_any_or_of_a_type_assignable_to_the_Function_interface_type: diag(2359, ts.DiagnosticCategory.Error, "The_right_hand_side_of_an_instanceof_expression_must_be_of_type_any_or_of_a_type_assignable_to_the_F_2359", "The right-hand side of an 'instanceof' expression must be of type 'any' or of a type assignable to the 'Function' interface type."),
         The_left_hand_side_of_an_in_expression_must_be_of_type_any_string_number_or_symbol: diag(2360, ts.DiagnosticCategory.Error, "The_left_hand_side_of_an_in_expression_must_be_of_type_any_string_number_or_symbol_2360", "The left-hand side of an 'in' expression must be of type 'any', 'string', 'number', or 'symbol'."),
-        The_right_hand_side_of_an_in_expression_must_be_of_type_any_an_object_type_or_a_type_parameter: diag(2361, ts.DiagnosticCategory.Error, "The_right_hand_side_of_an_in_expression_must_be_of_type_any_an_object_type_or_a_type_parameter_2361", "The right-hand side of an 'in' expression must be of type 'any', an object type or a type parameter."),
+        The_right_hand_side_of_an_in_expression_must_not_be_a_primitive: diag(2361, ts.DiagnosticCategory.Error, "The_right_hand_side_of_an_in_expression_must_not_be_a_primitive_2361", "The right-hand side of an 'in' expression must not be a primitive."),
         The_left_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_bigint_or_an_enum_type: diag(2362, ts.DiagnosticCategory.Error, "The_left_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_bigint_or_an_enum_type_2362", "The left-hand side of an arithmetic operation must be of type 'any', 'number', 'bigint' or an enum type."),
         The_right_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_bigint_or_an_enum_type: diag(2363, ts.DiagnosticCategory.Error, "The_right_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_bigint_or_an_enum_type_2363", "The right-hand side of an arithmetic operation must be of type 'any', 'number', 'bigint' or an enum type."),
         The_left_hand_side_of_an_assignment_expression_must_be_a_variable_or_a_property_access: diag(2364, ts.DiagnosticCategory.Error, "The_left_hand_side_of_an_assignment_expression_must_be_a_variable_or_a_property_access_2364", "The left-hand side of an assignment expression must be a variable or a property access."),
@@ -54880,15 +54880,18 @@ var ts;
             type.resolvedTypeArguments = source.resolvedTypeArguments;
             return type;
         }
-        function createDeferredTypeReference(target, node, mapper) {
-            var aliasSymbol = getAliasSymbolForTypeNode(node);
-            var aliasTypeArguments = getTypeArgumentsForAliasSymbol(aliasSymbol);
+        function createDeferredTypeReference(target, node, mapper, aliasSymbol, aliasTypeArguments) {
+            if (!aliasSymbol) {
+                aliasSymbol = getAliasSymbolForTypeNode(node);
+                var localAliasTypeArguments = getTypeArgumentsForAliasSymbol(aliasSymbol);
+                aliasTypeArguments = mapper ? instantiateTypes(localAliasTypeArguments, mapper) : localAliasTypeArguments;
+            }
             var type = createObjectType(4 /* Reference */, target.symbol);
             type.target = target;
             type.node = node;
             type.mapper = mapper;
             type.aliasSymbol = aliasSymbol;
-            type.aliasTypeArguments = mapper ? instantiateTypes(aliasTypeArguments, mapper) : aliasTypeArguments;
+            type.aliasTypeArguments = aliasTypeArguments;
             return type;
         }
         function getTypeArguments(type) {
@@ -54953,17 +54956,17 @@ var ts;
             }
             return checkNoTypeArguments(node, symbol) ? type : errorType;
         }
-        function getTypeAliasInstantiation(symbol, typeArguments) {
+        function getTypeAliasInstantiation(symbol, typeArguments, aliasSymbol, aliasTypeArguments) {
             var type = getDeclaredTypeOfSymbol(symbol);
             if (type === intrinsicMarkerType && intrinsicTypeKinds.has(symbol.escapedName) && typeArguments && typeArguments.length === 1) {
                 return getStringMappingType(symbol, typeArguments[0]);
             }
             var links = getSymbolLinks(symbol);
             var typeParameters = links.typeParameters;
-            var id = getTypeListId(typeArguments);
+            var id = getTypeListId(typeArguments) + (aliasSymbol ? "@" + getSymbolId(aliasSymbol) : "");
             var instantiation = links.instantiations.get(id);
             if (!instantiation) {
-                links.instantiations.set(id, instantiation = instantiateType(type, createTypeMapper(typeParameters, fillMissingTypeArguments(typeArguments, typeParameters, getMinTypeArgumentCount(typeParameters), ts.isInJSFile(symbol.valueDeclaration)))));
+                links.instantiations.set(id, instantiation = instantiateTypeWithAlias(type, createTypeMapper(typeParameters, fillMissingTypeArguments(typeArguments, typeParameters, getMinTypeArgumentCount(typeParameters), ts.isInJSFile(symbol.valueDeclaration))), aliasSymbol, aliasTypeArguments));
             }
             return instantiation;
         }
@@ -54984,7 +54987,8 @@ var ts;
                         ts.Diagnostics.Generic_type_0_requires_between_1_and_2_type_arguments, symbolToString(symbol), minTypeArgumentCount, typeParameters.length);
                     return errorType;
                 }
-                return getTypeAliasInstantiation(symbol, typeArgumentsFromTypeReferenceNode(node));
+                var aliasSymbol = getAliasSymbolForTypeNode(node);
+                return getTypeAliasInstantiation(symbol, typeArgumentsFromTypeReferenceNode(node), aliasSymbol, getTypeArgumentsForAliasSymbol(aliasSymbol));
             }
             return checkNoTypeArguments(node, symbol) ? type : errorType;
         }
@@ -56086,7 +56090,7 @@ var ts;
             var result = createType(2097152 /* Intersection */);
             result.objectFlags = getPropagatingFlagsOfTypes(types, /*excludeKinds*/ 98304 /* Nullable */);
             result.types = types;
-            result.aliasSymbol = aliasSymbol; // See comment in `getUnionTypeFromSortedList`.
+            result.aliasSymbol = aliasSymbol;
             result.aliasTypeArguments = aliasTypeArguments;
             return result;
         }
@@ -56928,7 +56932,7 @@ var ts;
             }
             return type;
         }
-        function getConditionalType(root, mapper) {
+        function getConditionalType(root, mapper, aliasSymbol, aliasTypeArguments) {
             var result;
             var extraTypes;
             // We loop here for an immediately nested conditional type in the false position, effectively treating
@@ -56995,8 +56999,8 @@ var ts;
                 result.extendsType = extendsType;
                 result.mapper = mapper;
                 result.combinedMapper = combinedMapper;
-                result.aliasSymbol = root.aliasSymbol;
-                result.aliasTypeArguments = instantiateTypes(root.aliasTypeArguments, mapper); // TODO: GH#18217
+                result.aliasSymbol = aliasSymbol || root.aliasSymbol;
+                result.aliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(root.aliasTypeArguments, mapper); // TODO: GH#18217
                 break;
             }
             return extraTypes ? getUnionType(ts.append(extraTypes, result)) : result;
@@ -57712,7 +57716,7 @@ var ts;
             }
             return result;
         }
-        function getObjectTypeInstantiation(type, mapper) {
+        function getObjectTypeInstantiation(type, mapper, aliasSymbol, aliasTypeArguments) {
             var declaration = type.objectFlags & 4 /* Reference */ ? type.node : type.symbol.declarations[0];
             var links = getNodeLinks(declaration);
             var target = type.objectFlags & 4 /* Reference */ ? links.resolvedType :
@@ -57740,17 +57744,19 @@ var ts;
                 // instantiation cache key from the type IDs of the type arguments.
                 var combinedMapper_1 = combineTypeMappers(type.mapper, mapper);
                 var typeArguments = ts.map(typeParameters, function (t) { return getMappedType(t, combinedMapper_1); });
-                var id = getTypeListId(typeArguments);
+                var newAliasSymbol = aliasSymbol || type.aliasSymbol;
+                var id = getTypeListId(typeArguments) + (newAliasSymbol ? "@" + getSymbolId(newAliasSymbol) : "");
                 if (!target.instantiations) {
                     target.instantiations = new ts.Map();
-                    target.instantiations.set(getTypeListId(typeParameters), target);
+                    target.instantiations.set(getTypeListId(typeParameters) + (target.aliasSymbol ? "@" + getSymbolId(target.aliasSymbol) : ""), target);
                 }
                 var result = target.instantiations.get(id);
                 if (!result) {
                     var newMapper = createTypeMapper(typeParameters, typeArguments);
-                    result = target.objectFlags & 4 /* Reference */ ? createDeferredTypeReference(type.target, type.node, newMapper) :
-                        target.objectFlags & 32 /* Mapped */ ? instantiateMappedType(target, newMapper) :
-                            instantiateAnonymousType(target, newMapper);
+                    var newAliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(type.aliasTypeArguments, mapper);
+                    result = target.objectFlags & 4 /* Reference */ ? createDeferredTypeReference(type.target, type.node, newMapper, newAliasSymbol, newAliasTypeArguments) :
+                        target.objectFlags & 32 /* Mapped */ ? instantiateMappedType(target, newMapper, newAliasSymbol, newAliasTypeArguments) :
+                            instantiateAnonymousType(target, newMapper, newAliasSymbol, newAliasTypeArguments);
                     target.instantiations.set(id, result);
                 }
                 return result;
@@ -57799,7 +57805,7 @@ var ts;
             }
             return undefined;
         }
-        function instantiateMappedType(type, mapper) {
+        function instantiateMappedType(type, mapper, aliasSymbol, aliasTypeArguments) {
             // For a homomorphic mapped type { [P in keyof T]: X }, where T is some type variable, the mapping
             // operation depends on T as follows:
             // * If T is a primitive type no mapping is performed and the result is simply T.
@@ -57814,7 +57820,7 @@ var ts;
             if (typeVariable) {
                 var mappedTypeVariable = instantiateType(typeVariable, mapper);
                 if (typeVariable !== mappedTypeVariable) {
-                    return mapType(getReducedType(mappedTypeVariable), function (t) {
+                    return mapTypeWithAlias(getReducedType(mappedTypeVariable), function (t) {
                         if (t.flags & (3 /* AnyOrUnknown */ | 58982400 /* InstantiableNonPrimitive */ | 524288 /* Object */ | 2097152 /* Intersection */) && t !== wildcardType && t !== errorType) {
                             if (!type.declaration.nameType) {
                                 if (isArrayType(t)) {
@@ -57830,11 +57836,11 @@ var ts;
                             return instantiateAnonymousType(type, prependTypeMapping(typeVariable, t, mapper));
                         }
                         return t;
-                    });
+                    }, aliasSymbol, aliasTypeArguments);
                 }
             }
             // If the constraint type of the instantiation is the wildcard type, return the wildcard type.
-            return instantiateType(getConstraintTypeFromMappedType(type), mapper) === wildcardType ? wildcardType : instantiateAnonymousType(type, mapper);
+            return instantiateType(getConstraintTypeFromMappedType(type), mapper) === wildcardType ? wildcardType : instantiateAnonymousType(type, mapper, aliasSymbol, aliasTypeArguments);
         }
         function getModifiedReadonlyState(state, modifiers) {
             return modifiers & 1 /* IncludeReadonly */ ? true : modifiers & 2 /* ExcludeReadonly */ ? false : state;
@@ -57881,7 +57887,7 @@ var ts;
                 strictNullChecks && modifiers & 8 /* ExcludeOptional */ && isOptional ? getTypeWithFacts(propType, 524288 /* NEUndefined */) :
                     propType;
         }
-        function instantiateAnonymousType(type, mapper) {
+        function instantiateAnonymousType(type, mapper, aliasSymbol, aliasTypeArguments) {
             var result = createObjectType(type.objectFlags | 64 /* Instantiated */, type.symbol);
             if (type.objectFlags & 32 /* Mapped */) {
                 result.declaration = type.declaration;
@@ -57894,29 +57900,29 @@ var ts;
             }
             result.target = type;
             result.mapper = mapper;
-            result.aliasSymbol = type.aliasSymbol;
-            result.aliasTypeArguments = instantiateTypes(type.aliasTypeArguments, mapper);
+            result.aliasSymbol = aliasSymbol || type.aliasSymbol;
+            result.aliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(type.aliasTypeArguments, mapper);
             return result;
         }
-        function getConditionalTypeInstantiation(type, mapper) {
+        function getConditionalTypeInstantiation(type, mapper, aliasSymbol, aliasTypeArguments) {
             var root = type.root;
             if (root.outerTypeParameters) {
                 // We are instantiating a conditional type that has one or more type parameters in scope. Apply the
                 // mapper to the type parameters to produce the effective list of type arguments, and compute the
                 // instantiation cache key from the type IDs of the type arguments.
                 var typeArguments = ts.map(root.outerTypeParameters, function (t) { return getMappedType(t, mapper); });
-                var id = getTypeListId(typeArguments);
+                var id = getTypeListId(typeArguments) + (aliasSymbol ? "@" + getSymbolId(aliasSymbol) : "");
                 var result = root.instantiations.get(id);
                 if (!result) {
                     var newMapper = createTypeMapper(root.outerTypeParameters, typeArguments);
-                    result = instantiateConditionalType(root, newMapper);
+                    result = instantiateConditionalType(root, newMapper, aliasSymbol, aliasTypeArguments);
                     root.instantiations.set(id, result);
                 }
                 return result;
             }
             return type;
         }
-        function instantiateConditionalType(root, mapper) {
+        function instantiateConditionalType(root, mapper, aliasSymbol, aliasTypeArguments) {
             // Check if we have a conditional type where the check type is a naked type parameter. If so,
             // the conditional type is distributive over union types and when T is instantiated to a union
             // type A | B, we produce (A extends U ? X : Y) | (B extends U ? X : Y).
@@ -57924,13 +57930,16 @@ var ts;
                 var checkType_1 = root.checkType;
                 var instantiatedType = getMappedType(checkType_1, mapper);
                 if (checkType_1 !== instantiatedType && instantiatedType.flags & (1048576 /* Union */ | 131072 /* Never */)) {
-                    return mapType(instantiatedType, function (t) { return getConditionalType(root, prependTypeMapping(checkType_1, t, mapper)); });
+                    return mapTypeWithAlias(instantiatedType, function (t) { return getConditionalType(root, prependTypeMapping(checkType_1, t, mapper)); }, aliasSymbol, aliasTypeArguments);
                 }
             }
-            return getConditionalType(root, mapper);
+            return getConditionalType(root, mapper, aliasSymbol, aliasTypeArguments);
         }
         function instantiateType(type, mapper) {
-            if (!(type && mapper && couldContainTypeVariables(type))) {
+            return type && mapper ? instantiateTypeWithAlias(type, mapper, /*aliasSymbol*/ undefined, /*aliasTypeArguments*/ undefined) : type;
+        }
+        function instantiateTypeWithAlias(type, mapper, aliasSymbol, aliasTypeArguments) {
+            if (!couldContainTypeVariables(type)) {
                 return type;
             }
             if (instantiationDepth === 50 || instantiationCount >= 5000000) {
@@ -57944,11 +57953,11 @@ var ts;
             totalInstantiationCount++;
             instantiationCount++;
             instantiationDepth++;
-            var result = instantiateTypeWorker(type, mapper);
+            var result = instantiateTypeWorker(type, mapper, aliasSymbol, aliasTypeArguments);
             instantiationDepth--;
             return result;
         }
-        function instantiateTypeWorker(type, mapper) {
+        function instantiateTypeWorker(type, mapper, aliasSymbol, aliasTypeArguments) {
             var flags = type.flags;
             if (flags & 262144 /* TypeParameter */) {
                 return getMappedType(type, mapper);
@@ -57956,12 +57965,12 @@ var ts;
             if (flags & 524288 /* Object */) {
                 var objectFlags = type.objectFlags;
                 if (objectFlags & (4 /* Reference */ | 16 /* Anonymous */ | 32 /* Mapped */)) {
-                    if (objectFlags & 4 /* Reference */ && !(type.node)) {
+                    if (objectFlags & 4 /* Reference */ && !type.node) {
                         var resolvedTypeArguments = type.resolvedTypeArguments;
                         var newTypeArguments = instantiateTypes(resolvedTypeArguments, mapper);
                         return newTypeArguments !== resolvedTypeArguments ? createNormalizedTypeReference(type.target, newTypeArguments) : type;
                     }
-                    return getObjectTypeInstantiation(type, mapper);
+                    return getObjectTypeInstantiation(type, mapper, aliasSymbol, aliasTypeArguments);
                 }
                 return type;
             }
@@ -57969,10 +57978,14 @@ var ts;
                 var origin = type.flags & 1048576 /* Union */ ? type.origin : undefined;
                 var types = origin && origin.flags & 3145728 /* UnionOrIntersection */ ? origin.types : type.types;
                 var newTypes = instantiateTypes(types, mapper);
-                return newTypes === types ? type :
-                    flags & 2097152 /* Intersection */ || origin && origin.flags & 2097152 /* Intersection */ ?
-                        getIntersectionType(newTypes, type.aliasSymbol, instantiateTypes(type.aliasTypeArguments, mapper)) :
-                        getUnionType(newTypes, 1 /* Literal */, type.aliasSymbol, instantiateTypes(type.aliasTypeArguments, mapper));
+                if (newTypes === types && aliasSymbol === type.aliasSymbol) {
+                    return type;
+                }
+                var newAliasSymbol = aliasSymbol || type.aliasSymbol;
+                var newAliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(type.aliasTypeArguments, mapper);
+                return flags & 2097152 /* Intersection */ || origin && origin.flags & 2097152 /* Intersection */ ?
+                    getIntersectionType(newTypes, newAliasSymbol, newAliasTypeArguments) :
+                    getUnionType(newTypes, 1 /* Literal */, newAliasSymbol, newAliasTypeArguments);
             }
             if (flags & 4194304 /* Index */) {
                 return getIndexType(instantiateType(type.type, mapper));
@@ -57984,10 +57997,12 @@ var ts;
                 return getStringMappingType(type.symbol, instantiateType(type.type, mapper));
             }
             if (flags & 8388608 /* IndexedAccess */) {
-                return getIndexedAccessType(instantiateType(type.objectType, mapper), instantiateType(type.indexType, mapper), type.noUncheckedIndexedAccessCandidate, /*accessNode*/ undefined, type.aliasSymbol, instantiateTypes(type.aliasTypeArguments, mapper));
+                var newAliasSymbol = aliasSymbol || type.aliasSymbol;
+                var newAliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(type.aliasTypeArguments, mapper);
+                return getIndexedAccessType(instantiateType(type.objectType, mapper), instantiateType(type.indexType, mapper), type.noUncheckedIndexedAccessCandidate, /*accessNode*/ undefined, newAliasSymbol, newAliasTypeArguments);
             }
             if (flags & 16777216 /* Conditional */) {
-                return getConditionalTypeInstantiation(type, combineTypeMappers(type.mapper, mapper));
+                return getConditionalTypeInstantiation(type, combineTypeMappers(type.mapper, mapper), aliasSymbol, aliasTypeArguments);
             }
             if (flags & 33554432 /* Substitution */) {
                 var maybeVariable = instantiateType(type.baseType, mapper);
@@ -63630,6 +63645,11 @@ var ts;
             }
             return changed ? mappedTypes && getUnionType(mappedTypes, noReductions ? 0 /* None */ : 1 /* Literal */) : type;
         }
+        function mapTypeWithAlias(type, mapper, aliasSymbol, aliasTypeArguments) {
+            return type.flags & 1048576 /* Union */ && aliasSymbol ?
+                getUnionType(ts.map(type.types, mapper), 1 /* Literal */, aliasSymbol, aliasTypeArguments) :
+                mapType(type, mapper);
+        }
         function getConstituentCount(type) {
             return type.flags & 3145728 /* UnionOrIntersection */ ? type.types.length : 1;
         }
@@ -63776,10 +63796,15 @@ var ts;
                         return getExplicitThisType(node);
                     case 105 /* SuperKeyword */:
                         return checkSuperExpression(node);
-                    case 201 /* PropertyAccessExpression */:
+                    case 201 /* PropertyAccessExpression */: {
                         var type = getTypeOfDottedName(node.expression, diagnostic);
-                        var prop = type && getPropertyOfType(type, node.name.escapedText);
-                        return prop && getExplicitTypeOfSymbol(prop, diagnostic);
+                        if (type) {
+                            var name = node.name;
+                            var prop = getPropertyOfType(type, ts.isPrivateIdentifier(name) ? ts.getSymbolNameForPrivateIdentifier(type.symbol, name.escapedText) : name.escapedText);
+                            return prop && getExplicitTypeOfSymbol(prop, diagnostic);
+                        }
+                        return undefined;
+                    }
                     case 207 /* ParenthesizedExpression */:
                         return getTypeOfDottedName(node.expression, diagnostic);
                 }
@@ -71444,14 +71469,33 @@ var ts;
             rightType = checkNonNullType(rightType, right);
             // TypeScript 1.0 spec (April 2014): 4.15.5
             // The in operator requires the left operand to be of type Any, the String primitive type, or the Number primitive type,
-            // and the right operand to be of type Any, an object type, or a type parameter type.
+            // and the right operand to be
+            //
+            //   1. assignable to the non-primitive type,
+            //   2. an unconstrained type parameter,
+            //   3. a union or intersection including one or more type parameters, whose constituents are all assignable to the
+            //      the non-primitive type, or are unconstrainted type parameters, or have constraints assignable to the
+            //      non-primitive type, or
+            //   4. a type parameter whose constraint is
+            //      i. an object type,
+            //     ii. the non-primitive type, or
+            //    iii. a union or intersection with at least one constituent assignable to an object or non-primitive type.
+            //
+            // The divergent behavior for type parameters and unions containing type parameters is a workaround for type
+            // parameters not being narrowable. If the right operand is a concrete type, we can error if there is any chance
+            // it is a primitive. But if the operand is a type parameter, it cannot be narrowed, so we don't issue an error
+            // unless *all* instantiations would result in an error.
+            //
             // The result is always of the Boolean primitive type.
             if (!(allTypesAssignableToKind(leftType, 402653316 /* StringLike */ | 296 /* NumberLike */ | 12288 /* ESSymbolLike */) ||
                 isTypeAssignableToKind(leftType, 4194304 /* Index */ | 134217728 /* TemplateLiteral */ | 268435456 /* StringMapping */ | 262144 /* TypeParameter */))) {
                 error(left, ts.Diagnostics.The_left_hand_side_of_an_in_expression_must_be_of_type_any_string_number_or_symbol);
             }
-            if (!allTypesAssignableToKind(rightType, 67108864 /* NonPrimitive */ | 58982400 /* InstantiableNonPrimitive */)) {
-                error(right, ts.Diagnostics.The_right_hand_side_of_an_in_expression_must_be_of_type_any_an_object_type_or_a_type_parameter);
+            var rightTypeConstraint = getConstraintOfType(rightType);
+            if (!allTypesAssignableToKind(rightType, 67108864 /* NonPrimitive */ | 58982400 /* InstantiableNonPrimitive */) ||
+                rightTypeConstraint && (isTypeAssignableToKind(rightType, 3145728 /* UnionOrIntersection */) && !allTypesAssignableToKind(rightTypeConstraint, 67108864 /* NonPrimitive */ | 58982400 /* InstantiableNonPrimitive */) ||
+                    !maybeTypeOfKind(rightTypeConstraint, 67108864 /* NonPrimitive */ | 58982400 /* InstantiableNonPrimitive */ | 524288 /* Object */))) {
+                error(right, ts.Diagnostics.The_right_hand_side_of_an_in_expression_must_not_be_a_primitive);
             }
             return booleanType;
         }

lib/typingsInstaller.js

@@ -7968,7 +7968,7 @@ var ts;
         The_left_hand_side_of_an_instanceof_expression_must_be_of_type_any_an_object_type_or_a_type_parameter: diag(2358, ts.DiagnosticCategory.Error, "The_left_hand_side_of_an_instanceof_expression_must_be_of_type_any_an_object_type_or_a_type_paramete_2358", "The left-hand side of an 'instanceof' expression must be of type 'any', an object type or a type parameter."),
         The_right_hand_side_of_an_instanceof_expression_must_be_of_type_any_or_of_a_type_assignable_to_the_Function_interface_type: diag(2359, ts.DiagnosticCategory.Error, "The_right_hand_side_of_an_instanceof_expression_must_be_of_type_any_or_of_a_type_assignable_to_the_F_2359", "The right-hand side of an 'instanceof' expression must be of type 'any' or of a type assignable to the 'Function' interface type."),
         The_left_hand_side_of_an_in_expression_must_be_of_type_any_string_number_or_symbol: diag(2360, ts.DiagnosticCategory.Error, "The_left_hand_side_of_an_in_expression_must_be_of_type_any_string_number_or_symbol_2360", "The left-hand side of an 'in' expression must be of type 'any', 'string', 'number', or 'symbol'."),
-        The_right_hand_side_of_an_in_expression_must_be_of_type_any_an_object_type_or_a_type_parameter: diag(2361, ts.DiagnosticCategory.Error, "The_right_hand_side_of_an_in_expression_must_be_of_type_any_an_object_type_or_a_type_parameter_2361", "The right-hand side of an 'in' expression must be of type 'any', an object type or a type parameter."),
+        The_right_hand_side_of_an_in_expression_must_not_be_a_primitive: diag(2361, ts.DiagnosticCategory.Error, "The_right_hand_side_of_an_in_expression_must_not_be_a_primitive_2361", "The right-hand side of an 'in' expression must not be a primitive."),
         The_left_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_bigint_or_an_enum_type: diag(2362, ts.DiagnosticCategory.Error, "The_left_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_bigint_or_an_enum_type_2362", "The left-hand side of an arithmetic operation must be of type 'any', 'number', 'bigint' or an enum type."),
         The_right_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_bigint_or_an_enum_type: diag(2363, ts.DiagnosticCategory.Error, "The_right_hand_side_of_an_arithmetic_operation_must_be_of_type_any_number_bigint_or_an_enum_type_2363", "The right-hand side of an arithmetic operation must be of type 'any', 'number', 'bigint' or an enum type."),
         The_left_hand_side_of_an_assignment_expression_must_be_a_variable_or_a_property_access: diag(2364, ts.DiagnosticCategory.Error, "The_left_hand_side_of_an_assignment_expression_must_be_a_variable_or_a_property_access_2364", "The left-hand side of an assignment expression must be a variable or a property access."),
@@ -54675,15 +54675,18 @@ var ts;
             type.resolvedTypeArguments = source.resolvedTypeArguments;
             return type;
         }
-        function createDeferredTypeReference(target, node, mapper) {
-            var aliasSymbol = getAliasSymbolForTypeNode(node);
-            var aliasTypeArguments = getTypeArgumentsForAliasSymbol(aliasSymbol);
+        function createDeferredTypeReference(target, node, mapper, aliasSymbol, aliasTypeArguments) {
+            if (!aliasSymbol) {
+                aliasSymbol = getAliasSymbolForTypeNode(node);
+                var localAliasTypeArguments = getTypeArgumentsForAliasSymbol(aliasSymbol);
+                aliasTypeArguments = mapper ? instantiateTypes(localAliasTypeArguments, mapper) : localAliasTypeArguments;
+            }
             var type = createObjectType(4 /* Reference */, target.symbol);
             type.target = target;
             type.node = node;
             type.mapper = mapper;
             type.aliasSymbol = aliasSymbol;
-            type.aliasTypeArguments = mapper ? instantiateTypes(aliasTypeArguments, mapper) : aliasTypeArguments;
+            type.aliasTypeArguments = aliasTypeArguments;
             return type;
         }
         function getTypeArguments(type) {
@@ -54748,17 +54751,17 @@ var ts;
             }
             return checkNoTypeArguments(node, symbol) ? type : errorType;
         }
-        function getTypeAliasInstantiation(symbol, typeArguments) {
+        function getTypeAliasInstantiation(symbol, typeArguments, aliasSymbol, aliasTypeArguments) {
             var type = getDeclaredTypeOfSymbol(symbol);
             if (type === intrinsicMarkerType && intrinsicTypeKinds.has(symbol.escapedName) && typeArguments && typeArguments.length === 1) {
                 return getStringMappingType(symbol, typeArguments[0]);
             }
             var links = getSymbolLinks(symbol);
             var typeParameters = links.typeParameters;
-            var id = getTypeListId(typeArguments);
+            var id = getTypeListId(typeArguments) + (aliasSymbol ? "@" + getSymbolId(aliasSymbol) : "");
             var instantiation = links.instantiations.get(id);
             if (!instantiation) {
-                links.instantiations.set(id, instantiation = instantiateType(type, createTypeMapper(typeParameters, fillMissingTypeArguments(typeArguments, typeParameters, getMinTypeArgumentCount(typeParameters), ts.isInJSFile(symbol.valueDeclaration)))));
+                links.instantiations.set(id, instantiation = instantiateTypeWithAlias(type, createTypeMapper(typeParameters, fillMissingTypeArguments(typeArguments, typeParameters, getMinTypeArgumentCount(typeParameters), ts.isInJSFile(symbol.valueDeclaration))), aliasSymbol, aliasTypeArguments));
             }
             return instantiation;
         }
@@ -54779,7 +54782,8 @@ var ts;
                         ts.Diagnostics.Generic_type_0_requires_between_1_and_2_type_arguments, symbolToString(symbol), minTypeArgumentCount, typeParameters.length);
                     return errorType;
                 }
-                return getTypeAliasInstantiation(symbol, typeArgumentsFromTypeReferenceNode(node));
+                var aliasSymbol = getAliasSymbolForTypeNode(node);
+                return getTypeAliasInstantiation(symbol, typeArgumentsFromTypeReferenceNode(node), aliasSymbol, getTypeArgumentsForAliasSymbol(aliasSymbol));
             }
             return checkNoTypeArguments(node, symbol) ? type : errorType;
         }
@@ -55881,7 +55885,7 @@ var ts;
             var result = createType(2097152 /* Intersection */);
             result.objectFlags = getPropagatingFlagsOfTypes(types, /*excludeKinds*/ 98304 /* Nullable */);
             result.types = types;
-            result.aliasSymbol = aliasSymbol; // See comment in `getUnionTypeFromSortedList`.
+            result.aliasSymbol = aliasSymbol;
             result.aliasTypeArguments = aliasTypeArguments;
             return result;
         }
@@ -56723,7 +56727,7 @@ var ts;
             }
             return type;
         }
-        function getConditionalType(root, mapper) {
+        function getConditionalType(root, mapper, aliasSymbol, aliasTypeArguments) {
             var result;
             var extraTypes;
             // We loop here for an immediately nested conditional type in the false position, effectively treating
@@ -56790,8 +56794,8 @@ var ts;
                 result.extendsType = extendsType;
                 result.mapper = mapper;
                 result.combinedMapper = combinedMapper;
-                result.aliasSymbol = root.aliasSymbol;
-                result.aliasTypeArguments = instantiateTypes(root.aliasTypeArguments, mapper); // TODO: GH#18217
+                result.aliasSymbol = aliasSymbol || root.aliasSymbol;
+                result.aliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(root.aliasTypeArguments, mapper); // TODO: GH#18217
                 break;
             }
             return extraTypes ? getUnionType(ts.append(extraTypes, result)) : result;
@@ -57507,7 +57511,7 @@ var ts;
             }
             return result;
         }
-        function getObjectTypeInstantiation(type, mapper) {
+        function getObjectTypeInstantiation(type, mapper, aliasSymbol, aliasTypeArguments) {
             var declaration = type.objectFlags & 4 /* Reference */ ? type.node : type.symbol.declarations[0];
             var links = getNodeLinks(declaration);
             var target = type.objectFlags & 4 /* Reference */ ? links.resolvedType :
@@ -57535,17 +57539,19 @@ var ts;
                 // instantiation cache key from the type IDs of the type arguments.
                 var combinedMapper_1 = combineTypeMappers(type.mapper, mapper);
                 var typeArguments = ts.map(typeParameters, function (t) { return getMappedType(t, combinedMapper_1); });
-                var id = getTypeListId(typeArguments);
+                var newAliasSymbol = aliasSymbol || type.aliasSymbol;
+                var id = getTypeListId(typeArguments) + (newAliasSymbol ? "@" + getSymbolId(newAliasSymbol) : "");
                 if (!target.instantiations) {
                     target.instantiations = new ts.Map();
-                    target.instantiations.set(getTypeListId(typeParameters), target);
+                    target.instantiations.set(getTypeListId(typeParameters) + (target.aliasSymbol ? "@" + getSymbolId(target.aliasSymbol) : ""), target);
                 }
                 var result = target.instantiations.get(id);
                 if (!result) {
                     var newMapper = createTypeMapper(typeParameters, typeArguments);
-                    result = target.objectFlags & 4 /* Reference */ ? createDeferredTypeReference(type.target, type.node, newMapper) :
-                        target.objectFlags & 32 /* Mapped */ ? instantiateMappedType(target, newMapper) :
-                            instantiateAnonymousType(target, newMapper);
+                    var newAliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(type.aliasTypeArguments, mapper);
+                    result = target.objectFlags & 4 /* Reference */ ? createDeferredTypeReference(type.target, type.node, newMapper, newAliasSymbol, newAliasTypeArguments) :
+                        target.objectFlags & 32 /* Mapped */ ? instantiateMappedType(target, newMapper, newAliasSymbol, newAliasTypeArguments) :
+                            instantiateAnonymousType(target, newMapper, newAliasSymbol, newAliasTypeArguments);
                     target.instantiations.set(id, result);
                 }
                 return result;
@@ -57594,7 +57600,7 @@ var ts;
             }
             return undefined;
         }
-        function instantiateMappedType(type, mapper) {
+        function instantiateMappedType(type, mapper, aliasSymbol, aliasTypeArguments) {
             // For a homomorphic mapped type { [P in keyof T]: X }, where T is some type variable, the mapping
             // operation depends on T as follows:
             // * If T is a primitive type no mapping is performed and the result is simply T.
@@ -57609,7 +57615,7 @@ var ts;
             if (typeVariable) {
                 var mappedTypeVariable = instantiateType(typeVariable, mapper);
                 if (typeVariable !== mappedTypeVariable) {
-                    return mapType(getReducedType(mappedTypeVariable), function (t) {
+                    return mapTypeWithAlias(getReducedType(mappedTypeVariable), function (t) {
                         if (t.flags & (3 /* AnyOrUnknown */ | 58982400 /* InstantiableNonPrimitive */ | 524288 /* Object */ | 2097152 /* Intersection */) && t !== wildcardType && t !== errorType) {
                             if (!type.declaration.nameType) {
                                 if (isArrayType(t)) {
@@ -57625,11 +57631,11 @@ var ts;
                             return instantiateAnonymousType(type, prependTypeMapping(typeVariable, t, mapper));
                         }
                         return t;
-                    });
+                    }, aliasSymbol, aliasTypeArguments);
                 }
             }
             // If the constraint type of the instantiation is the wildcard type, return the wildcard type.
-            return instantiateType(getConstraintTypeFromMappedType(type), mapper) === wildcardType ? wildcardType : instantiateAnonymousType(type, mapper);
+            return instantiateType(getConstraintTypeFromMappedType(type), mapper) === wildcardType ? wildcardType : instantiateAnonymousType(type, mapper, aliasSymbol, aliasTypeArguments);
         }
         function getModifiedReadonlyState(state, modifiers) {
             return modifiers & 1 /* IncludeReadonly */ ? true : modifiers & 2 /* ExcludeReadonly */ ? false : state;
@@ -57676,7 +57682,7 @@ var ts;
                 strictNullChecks && modifiers & 8 /* ExcludeOptional */ && isOptional ? getTypeWithFacts(propType, 524288 /* NEUndefined */) :
                     propType;
         }
-        function instantiateAnonymousType(type, mapper) {
+        function instantiateAnonymousType(type, mapper, aliasSymbol, aliasTypeArguments) {
             var result = createObjectType(type.objectFlags | 64 /* Instantiated */, type.symbol);
             if (type.objectFlags & 32 /* Mapped */) {
                 result.declaration = type.declaration;
@@ -57689,29 +57695,29 @@ var ts;
             }
             result.target = type;
             result.mapper = mapper;
-            result.aliasSymbol = type.aliasSymbol;
-            result.aliasTypeArguments = instantiateTypes(type.aliasTypeArguments, mapper);
+            result.aliasSymbol = aliasSymbol || type.aliasSymbol;
+            result.aliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(type.aliasTypeArguments, mapper);
             return result;
         }
-        function getConditionalTypeInstantiation(type, mapper) {
+        function getConditionalTypeInstantiation(type, mapper, aliasSymbol, aliasTypeArguments) {
             var root = type.root;
             if (root.outerTypeParameters) {
                 // We are instantiating a conditional type that has one or more type parameters in scope. Apply the
                 // mapper to the type parameters to produce the effective list of type arguments, and compute the
                 // instantiation cache key from the type IDs of the type arguments.
                 var typeArguments = ts.map(root.outerTypeParameters, function (t) { return getMappedType(t, mapper); });
-                var id = getTypeListId(typeArguments);
+                var id = getTypeListId(typeArguments) + (aliasSymbol ? "@" + getSymbolId(aliasSymbol) : "");
                 var result = root.instantiations.get(id);
                 if (!result) {
                     var newMapper = createTypeMapper(root.outerTypeParameters, typeArguments);
-                    result = instantiateConditionalType(root, newMapper);
+                    result = instantiateConditionalType(root, newMapper, aliasSymbol, aliasTypeArguments);
                     root.instantiations.set(id, result);
                 }
                 return result;
             }
             return type;
         }
-        function instantiateConditionalType(root, mapper) {
+        function instantiateConditionalType(root, mapper, aliasSymbol, aliasTypeArguments) {
             // Check if we have a conditional type where the check type is a naked type parameter. If so,
             // the conditional type is distributive over union types and when T is instantiated to a union
             // type A | B, we produce (A extends U ? X : Y) | (B extends U ? X : Y).
@@ -57719,13 +57725,16 @@ var ts;
                 var checkType_1 = root.checkType;
                 var instantiatedType = getMappedType(checkType_1, mapper);
                 if (checkType_1 !== instantiatedType && instantiatedType.flags & (1048576 /* Union */ | 131072 /* Never */)) {
-                    return mapType(instantiatedType, function (t) { return getConditionalType(root, prependTypeMapping(checkType_1, t, mapper)); });
+                    return mapTypeWithAlias(instantiatedType, function (t) { return getConditionalType(root, prependTypeMapping(checkType_1, t, mapper)); }, aliasSymbol, aliasTypeArguments);
                 }
             }
-            return getConditionalType(root, mapper);
+            return getConditionalType(root, mapper, aliasSymbol, aliasTypeArguments);
         }
         function instantiateType(type, mapper) {
-            if (!(type && mapper && couldContainTypeVariables(type))) {
+            return type && mapper ? instantiateTypeWithAlias(type, mapper, /*aliasSymbol*/ undefined, /*aliasTypeArguments*/ undefined) : type;
+        }
+        function instantiateTypeWithAlias(type, mapper, aliasSymbol, aliasTypeArguments) {
+            if (!couldContainTypeVariables(type)) {
                 return type;
             }
             if (instantiationDepth === 50 || instantiationCount >= 5000000) {
@@ -57739,11 +57748,11 @@ var ts;
             totalInstantiationCount++;
             instantiationCount++;
             instantiationDepth++;
-            var result = instantiateTypeWorker(type, mapper);
+            var result = instantiateTypeWorker(type, mapper, aliasSymbol, aliasTypeArguments);
             instantiationDepth--;
             return result;
         }
-        function instantiateTypeWorker(type, mapper) {
+        function instantiateTypeWorker(type, mapper, aliasSymbol, aliasTypeArguments) {
             var flags = type.flags;
             if (flags & 262144 /* TypeParameter */) {
                 return getMappedType(type, mapper);
@@ -57751,12 +57760,12 @@ var ts;
             if (flags & 524288 /* Object */) {
                 var objectFlags = type.objectFlags;
                 if (objectFlags & (4 /* Reference */ | 16 /* Anonymous */ | 32 /* Mapped */)) {
-                    if (objectFlags & 4 /* Reference */ && !(type.node)) {
+                    if (objectFlags & 4 /* Reference */ && !type.node) {
                         var resolvedTypeArguments = type.resolvedTypeArguments;
                         var newTypeArguments = instantiateTypes(resolvedTypeArguments, mapper);
                         return newTypeArguments !== resolvedTypeArguments ? createNormalizedTypeReference(type.target, newTypeArguments) : type;
                     }
-                    return getObjectTypeInstantiation(type, mapper);
+                    return getObjectTypeInstantiation(type, mapper, aliasSymbol, aliasTypeArguments);
                 }
                 return type;
             }
@@ -57764,10 +57773,14 @@ var ts;
                 var origin = type.flags & 1048576 /* Union */ ? type.origin : undefined;
                 var types = origin && origin.flags & 3145728 /* UnionOrIntersection */ ? origin.types : type.types;
                 var newTypes = instantiateTypes(types, mapper);
-                return newTypes === types ? type :
-                    flags & 2097152 /* Intersection */ || origin && origin.flags & 2097152 /* Intersection */ ?
-                        getIntersectionType(newTypes, type.aliasSymbol, instantiateTypes(type.aliasTypeArguments, mapper)) :
-                        getUnionType(newTypes, 1 /* Literal */, type.aliasSymbol, instantiateTypes(type.aliasTypeArguments, mapper));
+                if (newTypes === types && aliasSymbol === type.aliasSymbol) {
+                    return type;
+                }
+                var newAliasSymbol = aliasSymbol || type.aliasSymbol;
+                var newAliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(type.aliasTypeArguments, mapper);
+                return flags & 2097152 /* Intersection */ || origin && origin.flags & 2097152 /* Intersection */ ?
+                    getIntersectionType(newTypes, newAliasSymbol, newAliasTypeArguments) :
+                    getUnionType(newTypes, 1 /* Literal */, newAliasSymbol, newAliasTypeArguments);
             }
             if (flags & 4194304 /* Index */) {
                 return getIndexType(instantiateType(type.type, mapper));
@@ -57779,10 +57792,12 @@ var ts;
                 return getStringMappingType(type.symbol, instantiateType(type.type, mapper));
             }
             if (flags & 8388608 /* IndexedAccess */) {
-                return getIndexedAccessType(instantiateType(type.objectType, mapper), instantiateType(type.indexType, mapper), type.noUncheckedIndexedAccessCandidate, /*accessNode*/ undefined, type.aliasSymbol, instantiateTypes(type.aliasTypeArguments, mapper));
+                var newAliasSymbol = aliasSymbol || type.aliasSymbol;
+                var newAliasTypeArguments = aliasSymbol ? aliasTypeArguments : instantiateTypes(type.aliasTypeArguments, mapper);
+                return getIndexedAccessType(instantiateType(type.objectType, mapper), instantiateType(type.indexType, mapper), type.noUncheckedIndexedAccessCandidate, /*accessNode*/ undefined, newAliasSymbol, newAliasTypeArguments);
             }
             if (flags & 16777216 /* Conditional */) {
-                return getConditionalTypeInstantiation(type, combineTypeMappers(type.mapper, mapper));
+                return getConditionalTypeInstantiation(type, combineTypeMappers(type.mapper, mapper), aliasSymbol, aliasTypeArguments);
             }
             if (flags & 33554432 /* Substitution */) {
                 var maybeVariable = instantiateType(type.baseType, mapper);
@@ -63425,6 +63440,11 @@ var ts;
             }
             return changed ? mappedTypes && getUnionType(mappedTypes, noReductions ? 0 /* None */ : 1 /* Literal */) : type;
         }
+        function mapTypeWithAlias(type, mapper, aliasSymbol, aliasTypeArguments) {
+            return type.flags & 1048576 /* Union */ && aliasSymbol ?
+                getUnionType(ts.map(type.types, mapper), 1 /* Literal */, aliasSymbol, aliasTypeArguments) :
+                mapType(type, mapper);
+        }
         function getConstituentCount(type) {
             return type.flags & 3145728 /* UnionOrIntersection */ ? type.types.length : 1;
         }
@@ -63571,10 +63591,15 @@ var ts;
                         return getExplicitThisType(node);
                     case 105 /* SuperKeyword */:
                         return checkSuperExpression(node);
-                    case 201 /* PropertyAccessExpression */:
+                    case 201 /* PropertyAccessExpression */: {
                         var type = getTypeOfDottedName(node.expression, diagnostic);
-                        var prop = type && getPropertyOfType(type, node.name.escapedText);
-                        return prop && getExplicitTypeOfSymbol(prop, diagnostic);
+                        if (type) {
+                            var name = node.name;
+                            var prop = getPropertyOfType(type, ts.isPrivateIdentifier(name) ? ts.getSymbolNameForPrivateIdentifier(type.symbol, name.escapedText) : name.escapedText);
+                            return prop && getExplicitTypeOfSymbol(prop, diagnostic);
+                        }
+                        return undefined;
+                    }
                     case 207 /* ParenthesizedExpression */:
                         return getTypeOfDottedName(node.expression, diagnostic);
                 }
@@ -71239,14 +71264,33 @@ var ts;
             rightType = checkNonNullType(rightType, right);
             // TypeScript 1.0 spec (April 2014): 4.15.5
             // The in operator requires the left operand to be of type Any, the String primitive type, or the Number primitive type,
-            // and the right operand to be of type Any, an object type, or a type parameter type.
+            // and the right operand to be
+            //
+            //   1. assignable to the non-primitive type,
+            //   2. an unconstrained type parameter,
+            //   3. a union or intersection including one or more type parameters, whose constituents are all assignable to the
+            //      the non-primitive type, or are unconstrainted type parameters, or have constraints assignable to the
+            //      non-primitive type, or
+            //   4. a type parameter whose constraint is
+            //      i. an object type,
+            //     ii. the non-primitive type, or
+            //    iii. a union or intersection with at least one constituent assignable to an object or non-primitive type.
+            //
+            // The divergent behavior for type parameters and unions containing type parameters is a workaround for type
+            // parameters not being narrowable. If the right operand is a concrete type, we can error if there is any chance
+            // it is a primitive. But if the operand is a type parameter, it cannot be narrowed, so we don't issue an error
+            // unless *all* instantiations would result in an error.
+            //
             // The result is always of the Boolean primitive type.
             if (!(allTypesAssignableToKind(leftType, 402653316 /* StringLike */ | 296 /* NumberLike */ | 12288 /* ESSymbolLike */) ||
                 isTypeAssignableToKind(leftType, 4194304 /* Index */ | 134217728 /* TemplateLiteral */ | 268435456 /* StringMapping */ | 262144 /* TypeParameter */))) {
                 error(left, ts.Diagnostics.The_left_hand_side_of_an_in_expression_must_be_of_type_any_string_number_or_symbol);
             }
-            if (!allTypesAssignableToKind(rightType, 67108864 /* NonPrimitive */ | 58982400 /* InstantiableNonPrimitive */)) {
-                error(right, ts.Diagnostics.The_right_hand_side_of_an_in_expression_must_be_of_type_any_an_object_type_or_a_type_parameter);
+            var rightTypeConstraint = getConstraintOfType(rightType);
+            if (!allTypesAssignableToKind(rightType, 67108864 /* NonPrimitive */ | 58982400 /* InstantiableNonPrimitive */) ||
+                rightTypeConstraint && (isTypeAssignableToKind(rightType, 3145728 /* UnionOrIntersection */) && !allTypesAssignableToKind(rightTypeConstraint, 67108864 /* NonPrimitive */ | 58982400 /* InstantiableNonPrimitive */) ||
+                    !maybeTypeOfKind(rightTypeConstraint, 67108864 /* NonPrimitive */ | 58982400 /* InstantiableNonPrimitive */ | 524288 /* Object */))) {
+                error(right, ts.Diagnostics.The_right_hand_side_of_an_in_expression_must_not_be_a_primitive);
             }
             return booleanType;
         }