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| import * as parser from './query-parser.generated'; | |
| type CallNode = { | |
| type: 'Call'; | |
| method: string; | |
| arguments: ValueNode[]; | |
| }; | |
| type CallChainNode = { | |
| type: 'CallChain'; | |
| target: string; | |
| calls: CallNode[]; | |
| }; | |
| type ValueNode = CallChainNode | string | number | boolean | null | ValueNode[]; | |
| const FORBIDDEN_PROPERTY_NAMES = new Set(['__proto__', 'prototype', 'constructor']); | |
| function executeCallChain(node: CallChainNode, entryPoint: object): unknown { | |
| if (node.target !== 'Q') { | |
| throw new Error(`Unsupported query entry point ${node.target}; expected Q`); | |
| } | |
| let receiver: unknown = entryPoint; | |
| for (const call of node.calls) { | |
| if (FORBIDDEN_PROPERTY_NAMES.has(call.method)) { | |
| throw new Error(`Method ${call.method} is not allowed in a query expression`); | |
| } | |
| if ((typeof receiver !== 'object' && typeof receiver !== 'function') || receiver === null) { | |
| throw new Error(`Cannot call ${call.method} on a non-query value`); | |
| } | |
| const method = (receiver as Record<string, unknown>)[call.method]; | |
| if (typeof method !== 'function') { | |
| throw new Error(`Method ${call.method} is not available on the generated query API`); | |
| } | |
| const args = call.arguments.map(argument => | |
| typeof argument === 'object' && argument !== null && !Array.isArray(argument) | |
| ? executeCallChain(argument as CallChainNode, entryPoint) | |
| : argument, | |
| ); | |
| receiver = method.apply(receiver, args); | |
| } | |
| return receiver; | |
| } | |
| export class QueryParser { | |
| // The concrete return type is supplied by the generated entry point at runtime. | |
| // Keep `any` for source compatibility with existing generated Q facades. | |
| static parse(querySource: string, entryPoint: object): any { | |
| const ast = parser.parse(querySource, undefined) as CallChainNode; | |
| return executeCallChain(ast, entryPoint); | |
| } | |
| } | |