README

React prop types, ported to Twig.

Installation

With Composer:

composer require guym4c/twig-prop-types

Usage

This package makes guym4c/prop-types accessible in Twig. For documentation on how to use the prop types themselves, refer to that package.

Props in the Twig sense refers to the current context. You can use the only keyword in Twig to stop the context scope being inherited.

$twigEnv->addExtension(new Guym4c\TwigProps\PropTypesExtension($twigEnv, $bypass));

The extension constructor requires the current Twig environment and a flag to bypass the prop checker. You will probably want to prevent the validator from running in production, to avoid any performance issues. (This will not prevent default prop values being set.)

Validation

To validate your props, put the following at the top of a template file:

{{
    props({
        optionalNumber: PropTypes.number(),
        aString: PropTypes.string().isRequired(),
        anObject: PropTypes.instanceof('An.Instance.Of.This.Class'),
        heey: PropTypes.shape({
            maca: PropTypes.string().isRequired(),
            rena: PropTypes.string().isRequired(),
        }),
    })
}}

Twig-specific differences

When giving a fully-qualified classname when checking for an instance type, you may use dots instead of backslashes to simplify string escaping issues, and the leading backslash or dot is optional.

Advanced

You may pass additional properties to the constructor:

public function __construct(
    Twig\Environment $view,
    bool $bypass,
    string $typesGlobal = 'PropTypes',
    array $exclude = [],
    bool $allowExtraProperties = false
) {

• $twigEnv: the current Twig environment
• $bypass:
• $typesGlobal (optional): a custom name for the PropTypes global
• $exclude (optional): context variables to exclude from validation. Variables prefixed with an underscore _ (and the types global) are automatically excluded
• $allowExtraProperties (optional): Whether prop validation should fail if unexpected unexcluded extra props are found in the context (false by default)

Default values

If required, you must set default values of required props after the props() call to ensure that required props fail correctly if not provided.

{{
    props({
        someProp: PropTypes.string(),
    })  
    ~
    defaults({
        someProp: 'foo',
    })
}}

The props() and defaults() calls are separated by the Twig concatenate operator (~) so that they may be called in the same {{ output block }} without throwing an error. Both of these functions never return a value, so it is safe to do so.