@graphql-tools/graphql
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Fork of GraphQL.js
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JavaScript
import { GraphQLError } from '../../error/GraphQLError.js';
import { isInputObjectType, isInterfaceType, isObjectType } from '../../type/definition.js';
/**
* Unique field definition names
*
* A GraphQL complex type is only valid if all its fields are uniquely named.
*/
export function UniqueFieldDefinitionNamesRule(context) {
const schema = context.getSchema();
const existingTypeMap = schema ? schema.getTypeMap() : Object.create(null);
const knownFieldNames = Object.create(null);
return {
InputObjectTypeDefinition: checkFieldUniqueness,
InputObjectTypeExtension: checkFieldUniqueness,
InterfaceTypeDefinition: checkFieldUniqueness,
InterfaceTypeExtension: checkFieldUniqueness,
ObjectTypeDefinition: checkFieldUniqueness,
ObjectTypeExtension: checkFieldUniqueness,
};
function checkFieldUniqueness(node) {
var _a;
const typeName = node.name.value;
if (!knownFieldNames[typeName]) {
knownFieldNames[typeName] = Object.create(null);
}
// FIXME: https://github.com/graphql/graphql-js/issues/2203
/* c8 ignore next */
const fieldNodes = (_a = node.fields) !== null && _a !== void 0 ? _a : [];
const fieldNames = knownFieldNames[typeName];
for (const fieldDef of fieldNodes) {
const fieldName = fieldDef.name.value;
if (hasField(existingTypeMap[typeName], fieldName)) {
context.reportError(new GraphQLError(`Field "${typeName}.${fieldName}" already exists in the schema. It cannot also be defined in this type extension.`, { nodes: fieldDef.name }));
}
else if (fieldNames[fieldName]) {
context.reportError(new GraphQLError(`Field "${typeName}.${fieldName}" can only be defined once.`, {
nodes: [fieldNames[fieldName], fieldDef.name],
}));
}
else {
fieldNames[fieldName] = fieldDef.name;
}
}
return false;
}
}
function hasField(type, fieldName) {
if (isObjectType(type) || isInterfaceType(type) || isInputObjectType(type)) {
return type.getFields()[fieldName] != null;
}
return false;
}