Add toggle button for inline/side-by-side diff view

[Copilot]

VS Code's diff editor supports both inline and side-by-side rendering via the diffEditor.renderSideBySide setting, but lacked a UI toggle to switch between views.

Changes

Added ToggleDiffSideBySide action that:

• Toggles diffEditor.renderSideBySide configuration
• Appears in diff editor title bar with split-horizontal icon
• Button state reflects current mode via diffEditorInlineMode context key
• Accessible via command palette: "Diff Editor: Toggle Inline View"

Implementation

export class ToggleDiffSideBySide extends Action2 {
  constructor() {
    super({
      id: 'diffEditor.toggleDiffSideBySide',
      title: localize2('toggleDiffSideBySide', 'Toggle Inline View'),
      icon: Codicon.splitHorizontal,
      toggled: EditorContextKeys.diffEditorInlineMode.toNegated(),
      menu: {
        when: ContextKeyExpr.has('isInDiffEditor'),
        id: MenuId.EditorTitle,
        order: 21,
        group: 'navigation',
      },
    });
  }
}

Files modified:

• src/vs/editor/browser/widget/diffEditor/commands.ts - Added toggle action
• src/vs/editor/browser/widget/diffEditor/diffEditor.contribution.ts - Registered action

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Support for Inline Diff view in addition to Side by Side</issue_title>
<issue_description>This feature is requrest in jupyterlab, and I find it useful in jupyter for vscode as well, so I paste it here.

It would be great to be able to switch to an inline diff view in addition to the default side by side diff view.

Here is an example of this feature implemented in VS Code. Thanks!

</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Support for Inline Diff view in addition to Side by Side #227999

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