What causes "noUiSlider: 'padding' option must be a positive number." in Dogfalo/materialize?

Pass a non-negative number: padding: 10.

Dogfalo/materialize · error · Error

noUiSlider: 'padding' option must be a positive number.

Error message

noUiSlider: 'padding' option must be a positive number.

What it means

Thrown by testPadding when parsed.padding < 0, after getMargin converted the input to a percentage. padding must shrink the selectable region, so a negative input (which would expand it) is rejected. This check runs only after the linear-range check passes, so it is reached solely on linear sliders with a numeric padding.

Source

Thrown at extras/noUiSlider/nouislider.js:641

    function testPadding ( parsed, entry ) {

        if ( !isNumeric(entry) ){
            throw new Error("noUiSlider: 'padding' option must be numeric.");
        }

        if ( entry === 0 ) {
            return;
        }

        parsed.padding = parsed.spectrum.getMargin(entry);

        if ( !parsed.padding ) {
            throw new Error("noUiSlider: 'padding' option is only supported on linear sliders.");
        }

        if ( parsed.padding < 0 ) {
            throw new Error("noUiSlider: 'padding' option must be a positive number.");
        }

        if ( parsed.padding >= 50 ) {
            throw new Error("noUiSlider: 'padding' option must be less than half the range.");
        }
    }

    function testDirection ( parsed, entry ) {

        // Set direction as a numerical value for easy parsing.
        // Invert connection for RTL sliders, so that the proper
        // handles get the connect/background classes.
        switch ( entry ) {
            case 'ltr':
                parsed.dir = 0;
                break;
            case 'rtl':
                parsed.dir = 1;

View on GitHub (pinned to 824e78248b)

Solutions

Pass a non-negative number: padding: 10.
Clamp the computed value: Math.max(0, value).
Use 0 (or omit padding) to disable.

Example fix

// before
padding: -5
// after
padding: Math.max(0, p)

Defensive patterns

Strategy: validation

Validate before calling

if (opts.padding != null && opts.padding < 0) {
  throw new Error('padding must be non-negative');
}
// or clamp: opts.padding = Math.max(0, Number(opts.padding));

Try / catch

try { noUiSlider.create(el, opts); }
catch (e) { if (/padding' option must be a positive number/.test(e.message)) { opts.padding = Math.abs(opts.padding); /* retry */ } else throw e; }

Prevention

Clamp computed padding with Math.max(0, value) before passing it in.
Validate sign at the config boundary, especially for derived values.
Treat negative padding as a bug in the upstream calculation, not a feature.

When it happens

Trigger: padding: -10, a computed padding that goes negative, or padding: -0.0001 from rounding error.

Common situations: Subtracting a margin from a base value and going negative, a sign error in computation, or feeding an unclamped user input straight through.

Related errors

AI-assisted analysis of Dogfalo/materialize@824e78248b (2026-08-13). Data as JSON: /api/errors/f18cfc5328ffa7ad. Report an issue: GitHub.