| "use strict"; |
| var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) { |
| if (k2 === undefined) k2 = k; |
| Object.defineProperty(o, k2, { enumerable: true, get: function() { return m[k]; } }); |
| }) : (function(o, m, k, k2) { |
| if (k2 === undefined) k2 = k; |
| o[k2] = m[k]; |
| })); |
| var __setModuleDefault = (this && this.__setModuleDefault) || (Object.create ? (function(o, v) { |
| Object.defineProperty(o, "default", { enumerable: true, value: v }); |
| }) : function(o, v) { |
| o["default"] = v; |
| }); |
| var __importStar = (this && this.__importStar) || function (mod) { |
| if (mod && mod.__esModule) return mod; |
| var result = {}; |
| if (mod != null) for (var k in mod) if (k !== "default" && Object.prototype.hasOwnProperty.call(mod, k)) __createBinding(result, mod, k); |
| __setModuleDefault(result, mod); |
| return result; |
| }; |
| Object.defineProperty(exports, "__esModule", { value: true }); |
| const utils_1 = require("@typescript-eslint/utils"); |
| const tsutils = __importStar(require("tsutils")); |
| const ts = __importStar(require("typescript")); |
| const util = __importStar(require("../util")); |
| exports.default = util.createRule({ |
| name: 'no-misused-promises', |
| meta: { |
| docs: { |
| description: 'Avoid using promises in places not designed to handle them', |
| recommended: 'error', |
| requiresTypeChecking: true, |
| }, |
| messages: { |
| voidReturn: 'Promise returned in function argument where a void return was expected.', |
| conditional: 'Expected non-Promise value in a boolean conditional.', |
| }, |
| schema: [ |
| { |
| type: 'object', |
| properties: { |
| checksConditionals: { |
| type: 'boolean', |
| }, |
| checksVoidReturn: { |
| type: 'boolean', |
| }, |
| }, |
| }, |
| ], |
| type: 'problem', |
| }, |
| defaultOptions: [ |
| { |
| checksConditionals: true, |
| checksVoidReturn: true, |
| }, |
| ], |
| create(context, [{ checksConditionals, checksVoidReturn }]) { |
| const parserServices = util.getParserServices(context); |
| const checker = parserServices.program.getTypeChecker(); |
| const checkedNodes = new Set(); |
| const conditionalChecks = { |
| ConditionalExpression: checkTestConditional, |
| DoWhileStatement: checkTestConditional, |
| ForStatement: checkTestConditional, |
| IfStatement: checkTestConditional, |
| LogicalExpression: checkConditional, |
| 'UnaryExpression[operator="!"]'(node) { |
| checkConditional(node.argument, true); |
| }, |
| WhileStatement: checkTestConditional, |
| }; |
| const voidReturnChecks = { |
| CallExpression: checkArguments, |
| NewExpression: checkArguments, |
| }; |
| function checkTestConditional(node) { |
| if (node.test) { |
| checkConditional(node.test, true); |
| } |
| } |
| /** |
| * This function analyzes the type of a node and checks if it is a Promise in a boolean conditional. |
| * It uses recursion when checking nested logical operators. |
| * @param node The AST node to check. |
| * @param isTestExpr Whether the node is a descendant of a test expression. |
| */ |
| function checkConditional(node, isTestExpr = false) { |
| // prevent checking the same node multiple times |
| if (checkedNodes.has(node)) { |
| return; |
| } |
| checkedNodes.add(node); |
| if (node.type === utils_1.AST_NODE_TYPES.LogicalExpression) { |
| // ignore the left operand for nullish coalescing expressions not in a context of a test expression |
| if (node.operator !== '??' || isTestExpr) { |
| checkConditional(node.left, isTestExpr); |
| } |
| // we ignore the right operand when not in a context of a test expression |
| if (isTestExpr) { |
| checkConditional(node.right, isTestExpr); |
| } |
| return; |
| } |
| const tsNode = parserServices.esTreeNodeToTSNodeMap.get(node); |
| if (isAlwaysThenable(checker, tsNode)) { |
| context.report({ |
| messageId: 'conditional', |
| node, |
| }); |
| } |
| } |
| function checkArguments(node) { |
| const tsNode = parserServices.esTreeNodeToTSNodeMap.get(node); |
| const voidParams = voidFunctionParams(checker, tsNode); |
| if (voidParams.size === 0) { |
| return; |
| } |
| for (const [index, argument] of node.arguments.entries()) { |
| if (!voidParams.has(index)) { |
| continue; |
| } |
| const tsNode = parserServices.esTreeNodeToTSNodeMap.get(argument); |
| if (returnsThenable(checker, tsNode)) { |
| context.report({ |
| messageId: 'voidReturn', |
| node: argument, |
| }); |
| } |
| } |
| } |
| return Object.assign(Object.assign({}, (checksConditionals ? conditionalChecks : {})), (checksVoidReturn ? voidReturnChecks : {})); |
| }, |
| }); |
| // Variation on the thenable check which requires all forms of the type (read: |
| // alternates in a union) to be thenable. Otherwise, you might be trying to |
| // check if something is defined or undefined and get caught because one of the |
| // branches is thenable. |
| function isAlwaysThenable(checker, node) { |
| const type = checker.getTypeAtLocation(node); |
| for (const subType of tsutils.unionTypeParts(checker.getApparentType(type))) { |
| const thenProp = subType.getProperty('then'); |
| // If one of the alternates has no then property, it is not thenable in all |
| // cases. |
| if (thenProp === undefined) { |
| return false; |
| } |
| // We walk through each variation of the then property. Since we know it |
| // exists at this point, we just need at least one of the alternates to |
| // be of the right form to consider it thenable. |
| const thenType = checker.getTypeOfSymbolAtLocation(thenProp, node); |
| let hasThenableSignature = false; |
| for (const subType of tsutils.unionTypeParts(thenType)) { |
| for (const signature of subType.getCallSignatures()) { |
| if (signature.parameters.length !== 0 && |
| isFunctionParam(checker, signature.parameters[0], node)) { |
| hasThenableSignature = true; |
| break; |
| } |
| } |
| // We only need to find one variant of the then property that has a |
| // function signature for it to be thenable. |
| if (hasThenableSignature) { |
| break; |
| } |
| } |
| // If no flavors of the then property are thenable, we don't consider the |
| // overall type to be thenable |
| if (!hasThenableSignature) { |
| return false; |
| } |
| } |
| // If all variants are considered thenable (i.e. haven't returned false), we |
| // consider the overall type thenable |
| return true; |
| } |
| function isFunctionParam(checker, param, node) { |
| const type = checker.getApparentType(checker.getTypeOfSymbolAtLocation(param, node)); |
| for (const subType of tsutils.unionTypeParts(type)) { |
| if (subType.getCallSignatures().length !== 0) { |
| return true; |
| } |
| } |
| return false; |
| } |
| // Get the positions of parameters which are void functions (and not also |
| // thenable functions). These are the candidates for the void-return check at |
| // the current call site. |
| function voidFunctionParams(checker, node) { |
| const voidReturnIndices = new Set(); |
| const thenableReturnIndices = new Set(); |
| const type = checker.getTypeAtLocation(node.expression); |
| for (const subType of tsutils.unionTypeParts(type)) { |
| // Standard function calls and `new` have two different types of signatures |
| const signatures = ts.isCallExpression(node) |
| ? subType.getCallSignatures() |
| : subType.getConstructSignatures(); |
| for (const signature of signatures) { |
| for (const [index, parameter] of signature.parameters.entries()) { |
| const type = checker.getTypeOfSymbolAtLocation(parameter, node.expression); |
| for (const subType of tsutils.unionTypeParts(type)) { |
| for (const signature of subType.getCallSignatures()) { |
| const returnType = signature.getReturnType(); |
| if (tsutils.isTypeFlagSet(returnType, ts.TypeFlags.Void)) { |
| voidReturnIndices.add(index); |
| } |
| else if (tsutils.isThenableType(checker, node.expression, returnType)) { |
| thenableReturnIndices.add(index); |
| } |
| } |
| } |
| } |
| } |
| } |
| // If a certain positional argument accepts both thenable and void returns, |
| // a promise-returning function is valid |
| for (const thenable of thenableReturnIndices) { |
| voidReturnIndices.delete(thenable); |
| } |
| return voidReturnIndices; |
| } |
| // Returns true if the expression is a function that returns a thenable |
| function returnsThenable(checker, node) { |
| const type = checker.getApparentType(checker.getTypeAtLocation(node)); |
| for (const subType of tsutils.unionTypeParts(type)) { |
| for (const signature of subType.getCallSignatures()) { |
| const returnType = signature.getReturnType(); |
| if (tsutils.isThenableType(checker, node, returnType)) { |
| return true; |
| } |
| } |
| } |
| return false; |
| } |
| //# sourceMappingURL=no-misused-promises.js.map |