Form::Fieldset, Form::Header, Text::Display, Form:SuperSelect, Form::TextInput: small type fixes

[shleewhite]

📌 Summary

If merged, this PR would fix some type issues found while converting the forms routes to TypeScript.

• Form::Fieldset: export an array of the layout options
• Form::Header::Title: fix the type of the exported array of available tags
• Form::TextInput: fix the type of the exported array of available input types
• Text::Display: fix the type of the exported array of available text sizes

It also fixes a type issue with the @resultCountMessage argument for the Form::SuperSelect::Single and Form::SuperSelect::Multiple.

Before the fix, the type for @resultCountMessage was ((resultCount: number) => string) & string because the type was inherited from PowerSelectSignature['Args'] and also set in the interface, see:

This made it so the type was never correct if you set it to a string or a function.

The fix was to omit the arg from being inherited and only setting the type in the interface, see:

This type error happened because our custom after options component expects a string (link), while the actual power select component expects a function.

To resolve this, I just made different getters for each that return either a string or a function and then can be passed to the right place.

🔗 External links

Jira ticket: HDS-5101

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👀 Component checklist

• Percy was checked for any visual regression
• A changelog entry was added via Changesets if needed (see templates here)

💬 Please consider using conventional comments when reviewing this PR.

📋 PCI review checklist

• If applicable, I've documented a plan to revert these changes if they require more than reverting the pull request.
• If applicable, I've worked with GRC to document the impact of any changes to security controls.
  Examples of changes to controls include access controls, encryption, logging, etc.
• If applicable, I've worked with GRC to ensure compliance due to a significant change to the in-scope PCI environment.
  Examples include changes to operating systems, ports, protocols, services, cryptography-related components, PII processing code, etc.

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[Copilot]

Pull Request Overview

This PR fixes TypeScript typing issues across several form and text components and refines the @resultCountMessage argument in the single/multiple super-select components to cleanly accept either a string or a function.

• Export and cast enums’ values arrays to their proper literal types (HdsTextSizes[], HdsFormTextInputTypes[], HdsFormHeaderTitleTags[], HdsFormFieldsetLayouts[]).
• Omit the inherited resultCountMessage from PowerSelectSignature and redefine it as a union of string or function in both single and multiple super-select bases.
• Update Handlebars templates to wire up only the function variant to PowerSelect and add the corresponding changeset.

Reviewed Changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
packages/components/src/components/hds/text/display.ts	Cast AVAILABLE_SIZES to HdsTextSizes[]
packages/components/src/components/hds/form/text-input/base.ts	Typed TYPES as HdsFormTextInputTypes[]
packages/components/src/components/hds/form/super-select/single/base.ts	Omit and redefine resultCountMessage in the single base signature and add getters
packages/components/src/components/hds/form/super-select/single/base.hbs	Wire up function variant of resultCountMessage to PowerSelect
packages/components/src/components/hds/form/super-select/multiple/base.ts	Same signature and getters adjustments for multiple base
packages/components/src/components/hds/form/super-select/multiple/base.hbs	Wire up function variant of resultCountMessage to PowerSelect
packages/components/src/components/hds/form/header/title.ts	Typed AVAILABLE_TAGS as HdsFormHeaderTitleTags[]
packages/components/src/components/hds/form/fieldset/index.ts	Export typed LAYOUT_TYPES for fieldset layouts
.changeset/fresh-horses-wink.md	Added changeset entry for the super-select fix

Comments suppressed due to low confidence (3)

packages/components/src/components/hds/form/fieldset/index.ts:24

• [nitpick] To align with existing constants like AVAILABLE_SIZES and AVAILABLE_TAGS, consider renaming LAYOUT_TYPES to AVAILABLE_LAYOUTS or AVAILABLE_LAYOUT_TYPES for consistency.

export const LAYOUT_TYPES: HdsFormFieldsetLayouts[] = Object.values(

packages/components/src/components/hds/form/super-select/single/base.ts:57

• Consider adding unit tests to cover both the string and function cases for resultCountMessageFunction in the single super-select component to ensure this branching logic is verified.

  get resultCountMessageFunction() {

packages/components/src/components/hds/form/super-select/multiple/base.ts:68

• Add tests for the resultCountMessageFunction getter in the multiple super-select to validate that it correctly returns a function or undefined as intended.

  get resultCountMessageFunction() {

[dchyun]

A few minor / non-blocking comments but lgtm!

[didoo]

left a couple of comments