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'use strict';
Object.defineProperty(exports, '__esModule', {
value: true,
});
exports.VariablesInAllowedPositionRule = VariablesInAllowedPositionRule;
var _inspect = require('../../jsutils/inspect.js');
var _GraphQLError = require('../../error/GraphQLError.js');
var _kinds = require('../../language/kinds.js');
var _definition = require('../../type/definition.js');
var _typeComparators = require('../../utilities/typeComparators.js');
var _typeFromAST = require('../../utilities/typeFromAST.js');
/**
* Variables in allowed position
*
* Variable usages must be compatible with the arguments they are passed to.
*
* See https://spec.graphql.org/draft/#sec-All-Variable-Usages-are-Allowed
*/
function VariablesInAllowedPositionRule(context) {
let varDefMap = Object.create(null);
return {
OperationDefinition: {
enter() {
varDefMap = Object.create(null);
},
leave(operation) {
const usages = context.getRecursiveVariableUsages(operation);
for (const { node, type, defaultValue } of usages) {
const varName = node.name.value;
const varDef = varDefMap[varName];
if (varDef && type) {
// A var type is allowed if it is the same or more strict (e.g. is
// a subtype of) than the expected type. It can be more strict if
// the variable type is non-null when the expected type is nullable.
// If both are list types, the variable item type can be more strict
// than the expected item type (contravariant).
const schema = context.getSchema();
const varType = (0, _typeFromAST.typeFromAST)(schema, varDef.type);
if (
varType &&
!allowedVariableUsage(
schema,
varType,
varDef.defaultValue,
type,
defaultValue,
)
) {
const varTypeStr = (0, _inspect.inspect)(varType);
const typeStr = (0, _inspect.inspect)(type);
context.reportError(
new _GraphQLError.GraphQLError(
`Variable "$${varName}" of type "${varTypeStr}" used in position expecting type "${typeStr}".`,
{
nodes: [varDef, node],
},
),
);
}
}
}
},
},
VariableDefinition(node) {
varDefMap[node.variable.name.value] = node;
},
};
}
/**
* Returns true if the variable is allowed in the location it was found,
* which includes considering if default values exist for either the variable
* or the location at which it is located.
*/
function allowedVariableUsage(
schema,
varType,
varDefaultValue,
locationType,
locationDefaultValue,
) {
if (
(0, _definition.isNonNullType)(locationType) &&
!(0, _definition.isNonNullType)(varType)
) {
const hasNonNullVariableDefaultValue =
varDefaultValue != null && varDefaultValue.kind !== _kinds.Kind.NULL;
const hasLocationDefaultValue = locationDefaultValue !== undefined;
if (!hasNonNullVariableDefaultValue && !hasLocationDefaultValue) {
return false;
}
const nullableLocationType = locationType.ofType;
return (0, _typeComparators.isTypeSubTypeOf)(
schema,
varType,
nullableLocationType,
);
}
return (0, _typeComparators.isTypeSubTypeOf)(schema, varType, locationType);
}