chore(divider): refactor with abstracted base class

[Rajdeepc]

Overview

This PR refactors the sp-divider component to separate its base logic from rendering code, following the technical specifications for the Swan migration preparation. This is a purely internal change with no customer impact.

Changes Made

File Structure Changes

• Renamed: packages/divider/src/Divider.ts → packages/divider/src/Divider.base.ts (using git mv)
• Created: New packages/divider/src/Divider.ts with rendering logic only

Code Separation

DividerBase (Abstract Base Class)

• Location: packages/divider/src/Divider.base.ts
• Contains:
  • Property declarations (vertical)
  • Lifecycle methods (firstUpdated, updated)
  • Behavioral logic (ARIA attribute management)
  • All base functionality except rendering

Divider (Concrete Class)

• Location: packages/divider/src/Divider.ts
• Contains:
  • Class that extends DividerBase
  • Rendering logic (render() method)
  • Styles import and declaration

Technical Implementation

Before

export class Divider extends SizedMixin(SpectrumElement, {
    validSizes: ['s', 'm', 'l'],
    noDefaultSize: true,
}) {
    public static override styles: CSSResultArray = [styles];
    @property({ type: Boolean, reflect: true })
    public vertical = false;
    
    protected override render(): TemplateResult {
        return html``;
    }
    
    protected override firstUpdated(changed: PropertyValues<this>): void {
        // ... logic
    }
    
    protected override updated(changed: PropertyValues<this>): void {
        // ... logic
    }
}

After

// Divider.base.ts
export abstract class DividerBase extends SizedMixin(SpectrumElement, {
    validSizes: ['s', 'm', 'l'],
    noDefaultSize: true,
}) {
    @property({ type: Boolean, reflect: true })
    public vertical = false;
    
    protected override firstUpdated(changed: PropertyValues<this>): void {
        // ... logic
    }
    
    protected override updated(changed: PropertyValues<this>): void {
        // ... logic
    }
}

// Divider.ts
export class Divider extends DividerBase {
    public static override styles: CSSResultArray = [styles];
    
    protected override render(): TemplateResult {
        return html``;
    }
}

Impact

Customer Impact

• None - This is a purely internal refactoring
• Public API remains identical
• No visual or behavioral changes
• No breaking changes

Developer Impact

• None - Existing imports and usage patterns continue to work
• import { Divider } from '@spectrum-web-components/divider' still works
• All existing component usage remains valid

Related issue(s)

• fixes 979

Screenshots (if appropriate)

---

Author's checklist

• I have read the CONTRIBUTING and PULL_REQUESTS documents.
• I have reviewed at the Accessibility Practices for this feature, see: Aria Practices
• I have added automated tests to cover my changes.
• I have included a well-written changeset if my change needs to be published.
• I have included updated documentation if my change required it.

---

Reviewer's checklist

• Includes a Github Issue with appropriate flag or Jira ticket number without a link
• Includes thoughtfully written changeset if changes suggested include patch, minor, or major features
• Automated tests cover all use cases and follow best practices for writing
• Validated on all supported browsers
• All VRTs are approved before the author can update Golden Hash

Manual review test cases

• Manual Testing

  • Component renders correctly in Storybook
  • All variants (horizontal/vertical) work as expected
  • All sizes (s, m, l) display properly
  • ARIA attributes are set correctly

• Automated Testing

  • All existing tests pass
  • No new tests needed (no functional changes)

Device review

• Did it pass in Desktop?
• Did it pass in (emulated) Mobile?
• Did it pass in (emulated) iPad?

Migration Preparation

This refactoring prepares the divider component for future migration to the Swan architecture by:

1. Separating concerns - Base logic vs. rendering logic
2. Preserving git history - Base logic in Divider.base.ts will carry forward
3. Maintaining compatibility - Public API unchanged
4. Following established patterns - Consistent with other component refactoring

Related

• Epic: Swan Migration Preparation - Component Refactoring
• Technical Notes: Follows specified refactoring process for base logic extraction

[changeset-bot]

⚠️ No Changeset found

Latest commit: 0e470ff

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

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[github-actions]

📚 Branch Preview

• Documentation Site
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🔍 Visual Regression Test Results

When a visual regression test fails (or has previously failed while working on this branch), its results can be found in the following URLs:

• Spectrum | Light | Medium | LTR
• Spectrum | Dark | Large | RTL
• Express | Light | Medium | LTR
• Express | Dark | Large | RTL
• Spectrum-two | Light | Medium | LTR
• Spectrum-two | Dark | Large | RTL
• High Contrast Mode | Medium | LTR

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[github-actions]

Tachometer results

Currently, no packages are changed by this PR...

[TarunAdobe]

do we not have to add the newly added Divider.Base.ts to exports in package.json?

"exports": {
      ....
      "./src/Divider.base.js": {
          "development": "./src/Divider.base.dev.js",
          "default": "./src/Divider.base.js"
      },
      ....
 }

[nikkimk]

Lonely ghost terminates matchmaker (LGTM)