Rework AST to be more type safe and allow mutation

Package.resolved

@@ -15,8 +15,8 @@
         "repositoryURL": "https://github.com/apple/swift-nio.git",
         "state": {
           "branch": null,
-          "revision": "120acb15c39aa3217e9888e515de160378fbcc1e",
-          "version": "2.18.0"
+          "revision": "154f1d32366449dcccf6375a173adf4ed2a74429",
+          "version": "2.38.0"
         }
       }
     ]

Package.swift

@@ -7,7 +7,7 @@ let package = Package(
         .library(name: "GraphQL", targets: ["GraphQL"]),
     ],
     dependencies: [
-        .package(url: "https://github.com/apple/swift-nio.git", .upToNextMajor(from: "2.10.1")),
+        .package(url: "https://github.com/apple/swift-nio.git", .upToNextMajor(from: "2.38.0")),
         .package(url: "https://github.com/apple/swift-collections", .upToNextMajor(from: "1.0.0")),
     ],
     targets: [

Sources/GraphQL/Execution/Execute.swift

@@ -359,23 +359,21 @@ func buildExecutionContext(
 
     for definition in documentAST.definitions {
         switch definition {
-        case let definition as OperationDefinition:
+        case .executableDefinition(.operation(let definition)):
             guard !(operationName == nil && possibleOperation != nil) else {
                 throw GraphQLError(
                     message: "Must provide operation name if query contains multiple operations."
                 )
             }
-
+            
             if operationName == nil || definition.name?.value == operationName {
                 possibleOperation = definition
             }
-
-        case let definition as FragmentDefinition:
+        case .executableDefinition(.fragment(let definition)):
             fragments[definition.name.value] = definition
-
         default:
             throw GraphQLError(
-                message: "GraphQL cannot execute a request containing a \(definition.kind).",
+                message: "GraphQL cannot execute a request containing a \(type(of: definition)).",
                 nodes: [definition]
             )
         }
@@ -502,7 +500,7 @@ func collectFields(
 
     for selection in selectionSet.selections {
         switch selection {
-        case let field as Field:
+        case .field(let field):
             let shouldInclude = try shouldIncludeNode(
                 exeContext: exeContext,
                 directives: field.directives
@@ -519,7 +517,7 @@ func collectFields(
             }
 
             fields[name]?.append(field)
-        case let inlineFragment as InlineFragment:
+        case .inlineFragment(let inlineFragment):
             let shouldInclude = try shouldIncludeNode(
                 exeContext: exeContext,
                 directives: inlineFragment.directives
@@ -542,43 +540,41 @@ func collectFields(
                 fields: &fields,
                 visitedFragmentNames: &visitedFragmentNames
             )
-        case let fragmentSpread as FragmentSpread:
+        case .fragmentSpread(let fragmentSpread):
             let fragmentName = fragmentSpread.name.value
-
+            
             let shouldInclude = try shouldIncludeNode(
                 exeContext: exeContext,
                 directives: fragmentSpread.directives
             )
-
+            
             guard visitedFragmentNames[fragmentName] == nil && shouldInclude else {
                 continue
             }
-
+            
             visitedFragmentNames[fragmentName] = true
-
+            
             guard let fragment = exeContext.fragments[fragmentName] else {
                 continue
             }
-
+            
             let fragmentConditionMatches = try doesFragmentConditionMatch(
                 exeContext: exeContext,
                 fragment: fragment,
                 type: runtimeType
             )
-
+            
             guard fragmentConditionMatches else {
                 continue
             }
-
+            
             try collectFields(
                 exeContext: exeContext,
                 runtimeType: runtimeType,
                 selectionSet: fragment.selectionSet,
                 fields: &fields,
                 visitedFragmentNames: &visitedFragmentNames
             )
-        default:
-            break
         }
     }
 
@@ -629,15 +625,15 @@ func doesFragmentConditionMatch(
         return true
     }
 
-    guard let conditionalType = typeFromAST(schema: exeContext.schema, inputTypeAST: typeConditionAST) else {
+    guard let conditionalType = typeFromAST(schema: exeContext.schema, inputTypeAST: .namedType(typeConditionAST)) else {
         return true
     }
 
     if let conditionalType = conditionalType as? GraphQLObjectType, conditionalType.name == type.name {
         return true
     }
 
-    if let abstractType = conditionalType as? GraphQLAbstractType {
+    if let abstractType = conditionalType as? (any GraphQLAbstractType) {
         return exeContext.schema.isSubType(
             abstractType: abstractType,
             maybeSubType: type
@@ -765,7 +761,7 @@ func resolveOrError(
 // in the execution context.
 func completeValueCatchingError(
     exeContext: ExecutionContext,
-    returnType: GraphQLType,
+    returnType: any GraphQLType,
     fieldASTs: [Field],
     info: GraphQLResolveInfo,
     path: IndexPath,
@@ -817,7 +813,7 @@ func completeValueCatchingError(
 // location information.
 func completeValueWithLocatedError(
     exeContext: ExecutionContext,
-    returnType: GraphQLType,
+    returnType: any GraphQLType,
     fieldASTs: [Field],
     info: GraphQLResolveInfo,
     path: IndexPath,
@@ -867,7 +863,7 @@ func completeValueWithLocatedError(
  */
 func completeValue(
     exeContext: ExecutionContext,
-    returnType: GraphQLType,
+    returnType: any GraphQLType,
     fieldASTs: [Field],
     info: GraphQLResolveInfo,
     path: IndexPath,
@@ -916,13 +912,13 @@ func completeValue(
 
             // If field type is a leaf type, Scalar or Enum, serialize to a valid value,
             // returning .null if serialization is not possible.
-            if let returnType = returnType as? GraphQLLeafType {
+            if let returnType = returnType as? any GraphQLLeafType {
                 return exeContext.eventLoopGroup.next().makeSucceededFuture(try completeLeafValue(returnType: returnType, result: r))
             }
 
             // If field type is an abstract type, Interface or Union, determine the
             // runtime Object type and complete for that type.
-            if let returnType = returnType as? GraphQLAbstractType {
+            if let returnType = returnType as? any GraphQLAbstractType {
                 return try completeAbstractValue(
                     exeContext: exeContext,
                     returnType: returnType,
@@ -999,7 +995,7 @@ func completeListValue(
  * Complete a Scalar or Enum by serializing to a valid value, returning
  * .null if serialization is not possible.
  */
-func completeLeafValue(returnType: GraphQLLeafType, result: Any?) throws -> Map {
+func completeLeafValue(returnType: any GraphQLLeafType, result: Any?) throws -> Map {
     guard let result = result else {
         return .null
     }
@@ -1023,7 +1019,7 @@ func completeLeafValue(returnType: GraphQLLeafType, result: Any?) throws -> Map
  */
 func completeAbstractValue(
     exeContext: ExecutionContext,
-    returnType: GraphQLAbstractType,
+    returnType: any GraphQLAbstractType,
     fieldASTs: [Field],
     info: GraphQLResolveInfo,
     path: IndexPath,
@@ -1046,7 +1042,7 @@ func completeAbstractValue(
     }
 
     // If resolveType returns a string, we assume it's a GraphQLObjectType name.
-    var runtimeType: GraphQLType?
+    var runtimeType: (any GraphQLType)?
 
     switch resolveResult {
     case .name(let name):
@@ -1143,7 +1139,7 @@ func defaultResolveType(
     value: Any,
     eventLoopGroup: EventLoopGroup,
     info: GraphQLResolveInfo,
-    abstractType: GraphQLAbstractType
+    abstractType: any GraphQLAbstractType
 ) throws -> TypeResolveResult? {
     let possibleTypes = info.schema.getPossibleTypes(abstractType: abstractType)
 

Sources/GraphQL/Execution/Values.swift

@@ -82,7 +82,7 @@ func getVariableValue(schema: GraphQLSchema, definitionAST: VariableDefinition,
     let type = typeFromAST(schema: schema, inputTypeAST: definitionAST.type)
     let variable = definitionAST.variable
 
-    guard let inputType = type as? GraphQLInputType else {
+    guard let inputType = type as? (any GraphQLInputType) else {
         throw GraphQLError(
             message:
             "Variable \"$\(variable.name.value)\" expected value of type " +
@@ -112,11 +112,11 @@ func getVariableValue(schema: GraphQLSchema, definitionAST: VariableDefinition,
 /**
  * Given a type and any value, return a runtime value coerced to match the type.
  */
-func coerceValue(value: Map, type: GraphQLInputType) throws -> Map {
+func coerceValue(value: Map, type: any GraphQLInputType) throws -> Map {
     if let nonNull = type as? GraphQLNonNull {
         // Note: we're not checking that the result of coerceValue is non-null.
         // We only call this function after calling validate.
-        guard let nonNullType = nonNull.ofType as? GraphQLInputType else {
+        guard let nonNullType = nonNull.ofType as? (any GraphQLInputType) else {
             throw GraphQLError(message: "NonNull must wrap an input type")
         }
         return try coerceValue(value: value, type: nonNullType)
@@ -127,7 +127,7 @@ func coerceValue(value: Map, type: GraphQLInputType) throws -> Map {
     }
 
     if let list = type as? GraphQLList {
-        guard let itemType = list.ofType as? GraphQLInputType else {
+        guard let itemType = list.ofType as? (any GraphQLInputType) else {
             throw GraphQLError(message: "Input list must wrap an input type")
         }
 
@@ -168,7 +168,7 @@ func coerceValue(value: Map, type: GraphQLInputType) throws -> Map {
         return .dictionary(object)
     }
 
-    if let leafType = type as? GraphQLLeafType {
+    if let leafType = type as? (any GraphQLLeafType) {
         return try leafType.parseValue(value: value)
     }