io-ts-types/lib/withMessage.js

A collection of codecs and combinators for use with io-ts

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.withMessage = void 0;
var withValidate_1 = require("./withValidate");
var Either_1 = require("fp-ts/lib/Either");
/**
 * Returns a clone of the given codec that sets the given string as error messsage
 *
 * @example
 * import { withMessage } from 'io-ts-types/lib/withMessage'
 * import * as t from 'io-ts'
 * import { PathReporter } from 'io-ts/lib/PathReporter'
 * import { right } from 'fp-ts/lib/Either'
 *
 * const T = withMessage(t.number, () => 'Invalid number')
 *
 * assert.deepStrictEqual(T.decode(1), right(1))
 * assert.deepStrictEqual(PathReporter.report(T.decode(null)), ['Invalid number'])
 *
 * @since 0.4.3
 */
function withMessage(codec, message) {
    return withValidate_1.withValidate(codec, function (i, c) {
        return Either_1.mapLeft(function () { return [
            {
                value: i,
                context: c,
                message: message(i, c),
                actual: i
            }
        ]; })(codec.validate(i, c));
    });
}
exports.withMessage = withMessage;