UNPKG

@toreda/strong-types

Version:

Better TypeScript code in fewer lines.

78 lines (69 loc) 2.33 kB
/** * MIT License * * Copyright (c) 2019 - 2021 Toreda, Inc. * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * The above copyright notice and this permission notice shall be included in all * copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. * */ import {BaseObject} from '../base/object'; import {Rule} from '../rule'; import {RuleFn} from '../rule/fn'; import {RuleMods} from '../rule/mods'; import {RuleNode} from '../rule/node'; import {RuleNodeType} from '../rule/node/type'; /** * Type signature for hasProperty validators used in rule chains. * * @category Validators */ export type HasProperty<CallerT> = (propName: string) => CallerT; /** * * @param o * @param propName * @returns * * @category Validators */ export function hasProperty(o: unknown, propName: string): boolean { if (typeof o === 'undefined' || o === null) { return false; } const obj = o as BaseObject; return typeof obj[propName] !== 'undefined'; } /** * * @param caller * @param rule * @param mods * @returns * * @category Validator Factory Functions */ export function hasPropertyMake<CallerT>(caller: CallerT, rule: Rule, mods: RuleMods): HasProperty<CallerT> { return (propName: string): CallerT => { const fn: RuleFn<unknown> = (obj: unknown) => { return hasProperty(obj, propName); }; const node = new RuleNode<unknown>('HAS_PROPERTY', RuleNodeType.CMP, fn, mods); rule.add(node); return caller; }; }