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@polkadot/util

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"use strict"; Object.defineProperty(exports, "__esModule", { value: true }); exports.assert = assert; exports.assertReturn = assertReturn; exports.assertUnreachable = assertUnreachable; const function_js_1 = require("./is/function.js"); /** * @name assert * @summary Checks for a valid test, if not Error is thrown. * @description * Checks that `test` is a truthy value. If value is falsy (`null`, `undefined`, `false`, ...), it throws an Error with the supplied `message`. When `test` passes, `true` is returned. * @example * <BR> * * ```javascript * const { assert } from '@polkadot/util'; * * assert(true, 'True should be true'); // passes * assert(false, 'False should not be true'); // Error thrown * assert(false, () => 'message'); // Error with 'message' * ``` */ function assert(condition, message) { if (!condition) { throw new Error((0, function_js_1.isFunction)(message) ? message() : message); } } /** * @name assertReturn * @description Returns when the value is not undefined/null, otherwise throws assertion error */ function assertReturn(value, message) { assert(value !== undefined && value !== null, message); return value; } /** * @name assertUnreachable * @description An assertion helper that ensures all codepaths are followed */ function assertUnreachable(x) { throw new Error(`This codepath should be unreachable. Unhandled input: ${x}`); }