PropTypes.oneOf relies upon stringification when using Symbols

[aweary]

Original issue: facebook/react#9181

[deadratfink]

Hi, is there any chance that this can be fixed quickly? I still experience this error when passing a Symbol instance to a oneOf PropType. This is in factoryWithTypeCheckers.js -> line 289 ->

return new PropTypeError('Invalid ' + location + ' `' + propFullName + '` of value `' + propValue + '` ' + ('supplied to `' + componentName + '`, expected one of ' + valuesString + '.'));

which can be fixed easily by JSON.stringify around propValue:

return new PropTypeError('Invalid ' + location + ' `' + propFullName + '` of value `' + JSON.stringify(propValue) + '` ' + ('supplied to `' + componentName + '`, expected one of ' + valuesString + '.'));

STACKTRACE:

  console.log node_modules/check-prop-types/index.js:47
    TypeError: Cannot convert a Symbol value to a string
        at validate (.../node_modules/prop-types/factoryWithTypeCheckers.js:289:93)
        at checkType (.../node_modules/prop-types/factoryWithTypeCheckers.js:198:16)
        at checkPropTypes (.../node_modules/check-prop-types/index.js:37:44)
        at ReactComponentTest.expectPropTypes (...)
        at ReactComponentTest.expectPropTypesOfComponent (...)
        at Object.it (...)
        at Object.asyncFn (.../node_modules/jest-jasmine2/build/jasmine-async.js:68:30)
        at resolve (.../node_modules/jest-jasmine2/build/queueRunner.js:38:12)
        at new Promise (<anonymous>)
        at mapper (.../node_modules/jest-jasmine2/build/queueRunner.js:31:21)
        at Promise.resolve.then.el (.../node_modules/p-map/index.js:46:16)
        at <anonymous>
        at process._tickCallback (internal/process/next_tick.js:188:7)

[ljharb]

Using JSON is a bad idea because symbols stringify to null. Wrapping propValue in String() should be sufficient.

[deadratfink]

OK, looks like this depends on the environment running on, I just tried on Node.js 8.x during unit tests where I got

Failed prop type: Invalid prop `env` of value `42` supplied to `App.env`, expected one of ["development","shared","stage","production","test","storybook"].

when I provide Symbol(42) to the env property. As you can see the 42 is printed by JSON.stringify.

Of course, this should work out for the other environments:

• ... + String(propValue) + ... or
• ... + (typeof propValue === 'symbol' ? propValue.toString() : propValue) + ...

Anyway, hope this gets fixed soon 😃