graphql

TypesSource
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import { isNode } from '../language/ast.mjs';
import { Kind } from '../language/kinds.mjs';
import { getEnterLeaveForKind } from '../language/visitor.mjs';
import {
getNamedType,
getNullableType,
isCompositeType,
isEnumType,
isInputObjectType,
isInputType,
isInterfaceType,
isListType,
isObjectType,
isOutputType,
} from '../type/definition.mjs';
import {
SchemaMetaFieldDef,
TypeMetaFieldDef,
TypeNameMetaFieldDef,
} from '../type/introspection.mjs';
import { typeFromAST } from './typeFromAST.mjs';
/**
* TypeInfo is a utility class which, given a GraphQL schema, can keep track
* of the current field and type definitions at any point in a GraphQL document
* AST during a recursive descent by calling `enter(node)` and `leave(node)`.
*/
export class TypeInfo {
constructor(
schema,
/**
* Initial type may be provided in rare cases to facilitate traversals
* beginning somewhere other than documents.
*/
initialType,
/** @deprecated will be removed in 17.0.0 */
getFieldDefFn,
) {
this._schema = schema;
this._typeStack = [];
this._parentTypeStack = [];
this._inputTypeStack = [];
this._fieldDefStack = [];
this._defaultValueStack = [];
this._directive = null;
this._argument = null;
this._enumValue = null;
this._getFieldDef =
getFieldDefFn !== null && getFieldDefFn !== void 0
? getFieldDefFn
: getFieldDef;
if (initialType) {
if (isInputType(initialType)) {
this._inputTypeStack.push(initialType);
}
if (isCompositeType(initialType)) {
this._parentTypeStack.push(initialType);
}
if (isOutputType(initialType)) {
this._typeStack.push(initialType);
}
}
}
get [Symbol.toStringTag]() {
return 'TypeInfo';
}
getType() {
if (this._typeStack.length > 0) {
return this._typeStack[this._typeStack.length - 1];
}
}
getParentType() {
if (this._parentTypeStack.length > 0) {
return this._parentTypeStack[this._parentTypeStack.length - 1];
}
}
getInputType() {
if (this._inputTypeStack.length > 0) {
return this._inputTypeStack[this._inputTypeStack.length - 1];
}
}
getParentInputType() {
if (this._inputTypeStack.length > 1) {
return this._inputTypeStack[this._inputTypeStack.length - 2];
}
}
getFieldDef() {
if (this._fieldDefStack.length > 0) {
return this._fieldDefStack[this._fieldDefStack.length - 1];
}
}
getDefaultValue() {
if (this._defaultValueStack.length > 0) {
return this._defaultValueStack[this._defaultValueStack.length - 1];
}
}
getDirective() {
return this._directive;
}
getArgument() {
return this._argument;
}
getEnumValue() {
return this._enumValue;
}
enter(node) {
const schema = this._schema; // Note: many of the types below are explicitly typed as "unknown" to drop
// any assumptions of a valid schema to ensure runtime types are properly
// checked before continuing since TypeInfo is used as part of validation
// which occurs before guarantees of schema and document validity.
switch (node.kind) {
case Kind.SELECTION_SET: {
const namedType = getNamedType(this.getType());
this._parentTypeStack.push(
isCompositeType(namedType) ? namedType : undefined,
);
break;
}
case Kind.FIELD: {
const parentType = this.getParentType();
let fieldDef;
let fieldType;
if (parentType) {
fieldDef = this._getFieldDef(schema, parentType, node);
if (fieldDef) {
fieldType = fieldDef.type;
}
}
this._fieldDefStack.push(fieldDef);
this._typeStack.push(isOutputType(fieldType) ? fieldType : undefined);
break;
}
case Kind.DIRECTIVE:
this._directive = schema.getDirective(node.name.value);
break;
case Kind.OPERATION_DEFINITION: {
const rootType = schema.getRootType(node.operation);
this._typeStack.push(isObjectType(rootType) ? rootType : undefined);
break;
}
case Kind.INLINE_FRAGMENT:
case Kind.FRAGMENT_DEFINITION: {
const typeConditionAST = node.typeCondition;
const outputType = typeConditionAST
? typeFromAST(schema, typeConditionAST)
: getNamedType(this.getType());
this._typeStack.push(isOutputType(outputType) ? outputType : undefined);
break;
}
case Kind.VARIABLE_DEFINITION: {
const inputType = typeFromAST(schema, node.type);
this._inputTypeStack.push(
isInputType(inputType) ? inputType : undefined,
);
break;
}
case Kind.ARGUMENT: {
var _this$getDirective;
let argDef;
let argType;
const fieldOrDirective =
(_this$getDirective = this.getDirective()) !== null &&
_this$getDirective !== void 0
? _this$getDirective
: this.getFieldDef();
if (fieldOrDirective) {
argDef = fieldOrDirective.args.find(
(arg) => arg.name === node.name.value,
);
if (argDef) {
argType = argDef.type;
}
}
this._argument = argDef;
this._defaultValueStack.push(argDef ? argDef.defaultValue : undefined);
this._inputTypeStack.push(isInputType(argType) ? argType : undefined);
break;
}
case Kind.LIST: {
const listType = getNullableType(this.getInputType());
const itemType = isListType(listType) ? listType.ofType : listType; // List positions never have a default value.
this._defaultValueStack.push(undefined);
this._inputTypeStack.push(isInputType(itemType) ? itemType : undefined);
break;
}
case Kind.OBJECT_FIELD: {
const objectType = getNamedType(this.getInputType());
let inputFieldType;
let inputField;
if (isInputObjectType(objectType)) {
inputField = objectType.getFields()[node.name.value];
if (inputField) {
inputFieldType = inputField.type;
}
}
this._defaultValueStack.push(
inputField ? inputField.defaultValue : undefined,
);
this._inputTypeStack.push(
isInputType(inputFieldType) ? inputFieldType : undefined,
);
break;
}
case Kind.ENUM: {
const enumType = getNamedType(this.getInputType());
let enumValue;
if (isEnumType(enumType)) {
enumValue = enumType.getValue(node.value);
}
this._enumValue = enumValue;
break;
}
default: // Ignore other nodes
}
}
leave(node) {
switch (node.kind) {
case Kind.SELECTION_SET:
this._parentTypeStack.pop();
break;
case Kind.FIELD:
this._fieldDefStack.pop();
this._typeStack.pop();
break;
case Kind.DIRECTIVE:
this._directive = null;
break;
case Kind.OPERATION_DEFINITION:
case Kind.INLINE_FRAGMENT:
case Kind.FRAGMENT_DEFINITION:
this._typeStack.pop();
break;
case Kind.VARIABLE_DEFINITION:
this._inputTypeStack.pop();
break;
case Kind.ARGUMENT:
this._argument = null;
this._defaultValueStack.pop();
this._inputTypeStack.pop();
break;
case Kind.LIST:
case Kind.OBJECT_FIELD:
this._defaultValueStack.pop();
this._inputTypeStack.pop();
break;
case Kind.ENUM:
this._enumValue = null;
break;
default: // Ignore other nodes
}
}
}
/**
* Not exactly the same as the executor's definition of getFieldDef, in this
* statically evaluated environment we do not always have an Object type,
* and need to handle Interface and Union types.
*/
function getFieldDef(schema, parentType, fieldNode) {
const name = fieldNode.name.value;
if (
name === SchemaMetaFieldDef.name &&
schema.getQueryType() === parentType
) {
return SchemaMetaFieldDef;
}
if (name === TypeMetaFieldDef.name && schema.getQueryType() === parentType) {
return TypeMetaFieldDef;
}
if (name === TypeNameMetaFieldDef.name && isCompositeType(parentType)) {
return TypeNameMetaFieldDef;
}
if (isObjectType(parentType) || isInterfaceType(parentType)) {
return parentType.getFields()[name];
}
}
/**
* Creates a new visitor instance which maintains a provided TypeInfo instance
* along with visiting visitor.
*/
export function visitWithTypeInfo(typeInfo, visitor) {
return {
enter(...args) {
const node = args[0];
typeInfo.enter(node);
const fn = getEnterLeaveForKind(visitor, node.kind).enter;
if (fn) {
const result = fn.apply(visitor, args);
if (result !== undefined) {
typeInfo.leave(node);
if (isNode(result)) {
typeInfo.enter(result);
}
}
return result;
}
},
leave(...args) {
const node = args[0];
const fn = getEnterLeaveForKind(visitor, node.kind).leave;
let result;
if (fn) {
result = fn.apply(visitor, args);
}
typeInfo.leave(node);
return result;
},
};
}