feat: Set max height on a Select component

Is your feature request related to a problem? Please describe. I have a select component where the number of input elements is dynamic. It can be as few as 2 or 3 elements or even a few dozen. The problem is that if I don't set a height on a select component and I have lots of elements to display, the selection starts in the middle of the list.

If I set a fixed height, this fixes my problem for big lists:

However, for short lists, I get a UI that is too big:

Describe the solution you'd like My ideal UI would be what survey does by default:

For huh I would maybe imagine a .MaxHeight() method so that the small list would still fit the contents, but the big list would be contained within the MaxHeight value.

// Select is a form select field.
type Select[T comparable] struct {
    value    *T
    key      string
    viewport viewport.Model

    // customization
    title           string
    description     string
    options         []Option[T]
    filteredOptions []Option[T]
    height          int
+   maxHeight       int

...

+ func (s *Select[T]) MaxHeight(height int) *Select[T] {
+   s.maxHeight = height
+   s.updateViewportHeight()
+   return s
+ }

func (s *Select[T]) updateViewportHeight() {
    // If no height is set size the viewport to the number of options.
-   if s.height <= 0 {
-       s.viewport.Height = len(s.options)
-       return
-   }
+   if s.height <= 0 {
+       s.viewport.Height = min(len(s.options), s.maxHeight)
+       return
+   }

    // Wait until the theme has appied.
    if s.theme == nil {
        return
    }

    const minHeight = 1
-   s.viewport.Height = max(minHeight, s.height-
-       lipgloss.Height(s.titleView())-
-       lipgloss.Height(s.descriptionView()))
+   s.viewport.Height = max(minHeight, min(s.height-
+       lipgloss.Height(s.titleView())-
+       lipgloss.Height(s.descriptionView()), s.maxHeight))
}

This would result in the desired UI state:

Describe alternatives you've considered Have the .Height() method shrink to fit the contents by default and add a parameter to .Height() to allow users to make it a fixed height if they want.

Additional context Here's how I'm currently using the Select component:

// PromptSelect launches the selection UI
func PromptSelect(message string, options []string) (string, error) {
    var result string
    form := huh.NewForm(
        huh.NewGroup(
            huh.NewSelect[string]().
                Title(message).
                Height(10).
                Options(huh.NewOptions(options...)...).
                Value(&result),
        ),
    ).WithKeyMap(NewKeyMap())

    err := form.Run()
    if err != nil {
        return "", ExitUserSelectionError{Err: err}
    }
    return result, nil
}

charmbracelet / huh

feat: Set max height on a Select component #113