Addons / Knobs - When type is Number using the number knob, throws an error on delete and field is null

Describe the bug You have a knob, the prop type is Number and the default is number(‘something’, 0). If the user deletes the 0 (or all digits in the field), an error is thrown in the console because the value cannot be null

vendors~main.5317d89c4b17337a8714.bundle.js:103113 Warning: `value` prop on `input` should not be null. Consider using an empty string to clear the component or `undefined` for uncontrolled components.

To Reproduce Steps to reproduce the behavior:

1. Set a prop using a knob in a story

      hello: {
        type: Number,
        default: number('hello', 0),
      },

1. Use it in the template
2. Run the Storybook
3. Navigate to the story, delete the value in that knob field
4. See error in console

Expected behavior Either accept null (since it’s a valid value for Number) or on delete set back the default value or 0. I dunno whatever makes sense to you.

System:

Environment Info:

  System:
    OS: macOS 10.15.2
    CPU: (16) x64 Intel(R) Core(TM) i9-9880H CPU @ 2.30GHz
  Binaries:
    Node: 10.5.0 - ~/.nvm/versions/node/v10.5.0/bin/node
    npm: 6.1.0 - ~/.nvm/versions/node/v10.5.0/bin/npm
  Browsers:
    Chrome: 79.0.3945.117
    Firefox: 71.0
    Safari: 13.0.4
  npmPackages:
    @storybook/addon-a11y: ^5.0.3 => 5.1.9
    @storybook/addon-cssresources: ^5.0.11 => 5.1.9
    @storybook/addon-knobs: ^5.1.8 => 5.1.9
    @storybook/addon-notes: ^5.1.8 => 5.1.9
    @storybook/addon-viewport: ^5.1.8 => 5.1.9
    @storybook/theming: ^5.1.8 => 5.1.9
    @storybook/vue: ^5.2.8 => 5.2.8

Extra Right now to bypass that limitation, I use a String that I parse as a Number in the template…

[poblouin]

still an issue

[stale[bot]]

Hey there, it’s me again! I am going close this issue to help our maintainers focus on the current development roadmap instead. If the issue mentioned is still a concern, please open a new ticket and mention this old one. Cheers and thanks for using Storybook!