@typescript-eslint/eslint-plugin
Version:
TypeScript plugin for ESLint
119 lines (118 loc) • 4.73 kB
JavaScript
;
var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
if (k2 === undefined) k2 = k;
var desc = Object.getOwnPropertyDescriptor(m, k);
if (!desc || ("get" in desc ? !m.__esModule : desc.writable || desc.configurable)) {
desc = { enumerable: true, get: function() { return m[k]; } };
}
Object.defineProperty(o, k2, desc);
}) : (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 () {
var ownKeys = function(o) {
ownKeys = Object.getOwnPropertyNames || function (o) {
var ar = [];
for (var k in o) if (Object.prototype.hasOwnProperty.call(o, k)) ar[ar.length] = k;
return ar;
};
return ownKeys(o);
};
return function (mod) {
if (mod && mod.__esModule) return mod;
var result = {};
if (mod != null) for (var k = ownKeys(mod), i = 0; i < k.length; i++) if (k[i] !== "default") __createBinding(result, mod, k[i]);
__setModuleDefault(result, mod);
return result;
};
})();
Object.defineProperty(exports, "__esModule", { value: true });
exports.findTruthinessAssertedArgument = findTruthinessAssertedArgument;
exports.findTypeGuardAssertedArgument = findTypeGuardAssertedArgument;
const utils_1 = require("@typescript-eslint/utils");
const ts = __importStar(require("typescript"));
/**
* Inspect a call expression to see if it's a call to an assertion function.
* If it is, return the node of the argument that is asserted.
*/
function findTruthinessAssertedArgument(services, node) {
// If the call looks like `assert(expr1, expr2, ...c, d, e, f)`, then we can
// only care if `expr1` or `expr2` is asserted, since anything that happens
// within or after a spread argument is out of scope to reason about.
const checkableArguments = [];
for (const argument of node.arguments) {
if (argument.type === utils_1.AST_NODE_TYPES.SpreadElement) {
break;
}
checkableArguments.push(argument);
}
// nothing to do
if (checkableArguments.length === 0) {
return undefined;
}
const checker = services.program.getTypeChecker();
const tsNode = services.esTreeNodeToTSNodeMap.get(node);
const signature = checker.getResolvedSignature(tsNode);
if (signature == null) {
return undefined;
}
const firstTypePredicateResult = checker.getTypePredicateOfSignature(signature);
if (firstTypePredicateResult == null) {
return undefined;
}
const { kind, parameterIndex, type } = firstTypePredicateResult;
if (!(kind === ts.TypePredicateKind.AssertsIdentifier && type == null)) {
return undefined;
}
return checkableArguments.at(parameterIndex);
}
/**
* Inspect a call expression to see if it's a call to an assertion function.
* If it is, return the node of the argument that is asserted and other useful info.
*/
function findTypeGuardAssertedArgument(services, node) {
// If the call looks like `assert(expr1, expr2, ...c, d, e, f)`, then we can
// only care if `expr1` or `expr2` is asserted, since anything that happens
// within or after a spread argument is out of scope to reason about.
const checkableArguments = [];
for (const argument of node.arguments) {
if (argument.type === utils_1.AST_NODE_TYPES.SpreadElement) {
break;
}
checkableArguments.push(argument);
}
// nothing to do
if (checkableArguments.length === 0) {
return undefined;
}
const checker = services.program.getTypeChecker();
const tsNode = services.esTreeNodeToTSNodeMap.get(node);
const callSignature = checker.getResolvedSignature(tsNode);
if (callSignature == null) {
return undefined;
}
const typePredicateInfo = checker.getTypePredicateOfSignature(callSignature);
if (typePredicateInfo == null) {
return undefined;
}
const { kind, parameterIndex, type } = typePredicateInfo;
if (!((kind === ts.TypePredicateKind.AssertsIdentifier ||
kind === ts.TypePredicateKind.Identifier) &&
type != null)) {
return undefined;
}
if (parameterIndex >= checkableArguments.length) {
return undefined;
}
return {
argument: checkableArguments[parameterIndex],
asserts: kind === ts.TypePredicateKind.AssertsIdentifier,
type,
};
}