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'use strict';
Object.defineProperty(exports, '__esModule', {
value: true,
});
exports.PossibleFragmentSpreadsRule = PossibleFragmentSpreadsRule;
var _inspect = require('../../jsutils/inspect.js');
var _GraphQLError = require('../../error/GraphQLError.js');
var _definition = require('../../type/definition.js');
var _typeComparators = require('../../utilities/typeComparators.js');
var _typeFromAST = require('../../utilities/typeFromAST.js');
/** @category Validation Rules */
/**
* Possible fragment spread
*
* A fragment spread is only valid if the type condition could ever possibly
* be true: if there is a non-empty intersection of the possible parent types,
* and possible types which pass the type condition.
* @param context - The validation context used while checking the document.
* @returns A visitor that reports validation errors for this rule.
* @example
* ```ts
* import { buildSchema, parse, validate } from 'graphql';
* import { PossibleFragmentSpreadsRule } from 'graphql/validation';
*
* const schema = buildSchema(`
* type Query {
* dog: Dog
* }
*
* type Dog {
* barkVolume: Int
* }
*
* type Cat {
* meowVolume: Int
* }
* `);
*
* const invalidDocument = parse(`
* { dog { ... on Cat { meowVolume } } }
* `);
* const invalidErrors = validate(schema, invalidDocument, [PossibleFragmentSpreadsRule]);
*
* invalidErrors.length; // => 1
*
* const validDocument = parse(`
* { dog { ... on Dog { barkVolume } } }
* `);
* const validErrors = validate(schema, validDocument, [PossibleFragmentSpreadsRule]);
*
* validErrors; // => []
* ```
*/
function PossibleFragmentSpreadsRule(context) {
return {
InlineFragment(node) {
const fragType = context.getType();
const parentType = context.getParentType();
if (
(0, _definition.isCompositeType)(fragType) &&
(0, _definition.isCompositeType)(parentType) &&
!(0, _typeComparators.doTypesOverlap)(
context.getSchema(),
fragType,
parentType,
)
) {
const parentTypeStr = (0, _inspect.inspect)(parentType);
const fragTypeStr = (0, _inspect.inspect)(fragType);
context.reportError(
new _GraphQLError.GraphQLError(
`Fragment cannot be spread here as objects of type "${parentTypeStr}" can never be of type "${fragTypeStr}".`,
{
nodes: node,
},
),
);
}
},
FragmentSpread(node) {
const fragName = node.name.value;
const fragType = getFragmentType(context, fragName);
const parentType = context.getParentType();
if (
fragType &&
parentType &&
!(0, _typeComparators.doTypesOverlap)(
context.getSchema(),
fragType,
parentType,
)
) {
const parentTypeStr = (0, _inspect.inspect)(parentType);
const fragTypeStr = (0, _inspect.inspect)(fragType);
context.reportError(
new _GraphQLError.GraphQLError(
`Fragment "${fragName}" cannot be spread here as objects of type "${parentTypeStr}" can never be of type "${fragTypeStr}".`,
{
nodes: node,
},
),
);
}
},
};
}
function getFragmentType(context, name) {
const frag = context.getFragment(name);
if (frag) {
const type = (0, _typeFromAST.typeFromAST)(
context.getSchema(),
frag.typeCondition,
);
if ((0, _definition.isCompositeType)(type)) {
return type;
}
}
}