The warning for uncontrolled -> controlled inputs is confusing

[vcarl]

Do you want to request a feature or report a bug?

Bug? Mild DX improvement.

What is the current behavior?

Creating an input with an undefined or null value, then later passing a string value, triggers a warning about controlled inputs.

A component is changing an uncontrolled input of type undefined to be controlled. Input elements should not switch from uncontrolled to controlled (or vice versa)

It's my experience in Reactiflux that this warning is unclear to developers with less familiarity with React, or at least with the "controlled" and "uncontrolled" terms.

[bvaughn]

FWIW the full warning text is:

A component is changing an uncontrolled input of type %s to be controlled. Input elements should not switch from uncontrolled to controlled (or vice versa). Decide between using a controlled or uncontrolled input element for the lifetime of the component. More info: https://fb.me/react-controlled-components

I agree that developers may be unfamiliar with the terms "controlled" and "uncontrolled" but that's why we link to the documentation explaining what those terms mean 😄

[vcarl]

True, but I still think the lede of "you didn't give it a value, then you did" is pretty buried. This warning feels like it gets asked about more frequently than any other.

[markerikson]

fwiw, I can vouch that this comes up fairly often.

I would suggest adding a sentence like "This is likely caused by value={something} changing from undefined to a defined value".

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contribution.

[markerikson]

definitely not stale - #17390 is in progress.

[vcarl]

#17070 as well

[sammy007]

This warning must be removed it does not makes sense and only leads to tons of stupid empty field definitions just to get rid of it. If react is implemented the way it can't handle that it must be abandoned as dumb and poorly implemented library.