@typescript-eslint/eslint-plugin
Version:
TypeScript plugin for ESLint
61 lines (60 loc) • 2.71 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;
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};
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};
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.isPossiblyTruthy = exports.isPossiblyFalsy = void 0;
const tsutils = __importStar(require("ts-api-utils"));
const ts = __importStar(require("typescript"));
const getValueOfLiteralType_1 = require("./getValueOfLiteralType");
// Truthiness utilities
const isTruthyLiteral = (type) => tsutils.isTrueLiteralType(type) ||
(type.isLiteral() && !!(0, getValueOfLiteralType_1.getValueOfLiteralType)(type));
const isPossiblyFalsy = (type) => tsutils
.unionTypeParts(type)
// Intersections like `string & {}` can also be possibly falsy,
// requiring us to look into the intersection.
.flatMap(type => tsutils.intersectionTypeParts(type))
// PossiblyFalsy flag includes literal values, so exclude ones that
// are definitely truthy
.filter(t => !isTruthyLiteral(t))
.some(type => tsutils.isTypeFlagSet(type, ts.TypeFlags.PossiblyFalsy));
exports.isPossiblyFalsy = isPossiblyFalsy;
const isPossiblyTruthy = (type) => tsutils
.unionTypeParts(type)
.map(type => tsutils.intersectionTypeParts(type))
.some(intersectionParts =>
// It is possible to define intersections that are always falsy,
// like `"" & { __brand: string }`.
intersectionParts.every(type => !tsutils.isFalsyType(type)));
exports.isPossiblyTruthy = isPossiblyTruthy;