How it works

Usage

import * as React from 'react'
import * as t from 'io-ts'
import { props } from 'prop-types-ts'
// define the runtime types
const AlertType = t.keyof(
 {
 success: true,
 warning: true,
 info: true
 },
 'AlertType'
)
const RuntimeProps = t.interface(
 {
 type: AlertType
 },
 'Props'
)
// extract the static type
export type Props = t.TypeOf<typeof RuntimeProps>
// same as type Props = { type: 'success' | 'warning' | 'info' }
@props(RuntimeProps)
export default class Alert extends React.Component<Props, void> {
 render() {
 return <div>{this.props.children}</div>
 }
}

Without decorators

import { getPropTypes } from 'prop-types-ts'
...
export default class Alert extends React.Component<Props, void> {
 static propTypes = getPropTypes(RuntimeProps)
 render() {
 return <div>{this.props.children}</div>
 }
}

Errors on console

<Alert type="foo" /> // => Invalid value "foo" supplied to : Props/type: AlertType

<Alert type="info" foo="bar" /> // => Invalid additional prop(s): ["foo"]

Excess Property Checks

@props(RuntimeProps, { strict: false })
export default class Alert extends React.Component<Props, void> {
 ...
}

Pre-defined types

Type checking children

@props(RuntimeProps, { children: t.string })
export default class Alert extends React.Component<Props, void> {
 ...
}
<Alert type="info">{1}</Alert>// => Invalid value 1 supplied to children: string
<Alert type="info">hello</Alert>// no errors

import { props, ReactChild } from 'prop-types-ts'
@props(RuntimeProps, { children: t.tuple([t.string, ReactChild]) })
export default class Alert extends React.Component<Props, void> {
 ...
}
<Alert type="info">hello</Alert>// => Invalid value "hello" supplied to children: [string, ReactChild]
<Alert type="info">hello <b>world</b></Alert> // no errors

import * as t from 'io-ts'
import { props, ReactElement } from 'prop-types-ts'
const JSXButton = t.refinement(ReactElement, e => e.type === 'button', 'JSXButton')
@props(RuntimeProps, { children: JSXButton })
export default class Alert extends React.Component<Props, void> {
 ...
}
<Alert type="info">hello</Alert>// => Invalid value "hello" supplied to children: JSXButton
<Alert type="info"><button>Click me</button></Alert> // no errors

TypeScript compatibility