Changed-file trees and diff context

Desktop Material can organize changed files by directory and remember how much surrounding text to reveal. Both features are presentation preferences: they do not modify repository files, Git patches, staging selection, or history.

Flat and tree file lists

The Flat and Tree control appears in Changes, commit History, and pull request changed-file lists. The choice is shared across those surfaces and is persisted locally. Flat preserves the source list order. Tree uses a stable, ordinal path sort and depth-first directory ordering.

Tree rows keep the original file objects and identifiers. Selecting, checking, opening, double-clicking, filtering, and invoking a context menu therefore act on the same file as in Flat mode. Directory rows are non-selectable. Nested file rows show a compact basename, while their full Git path remains the accessible row name and the target for every action.

Git paths are grouped only when they are relative, control-character-free, no longer than 4,096 characters, no deeper than 128 segments, and contain no empty, . or .. segment. A path outside those rules remains an ordinary root-level leaf. The view never resolves paths on disk, so directory grouping cannot escape the repository or turn a display path into a filesystem action.

Persisted diff context

Diff Options includes two preferences:

• Automatically expand whole-file context opens eligible text diffs with all available surrounding lines.
• Context expansion step changes manual hunk expansion to 20, 50, or 100 lines per action.

Automatic expansion is deliberately bounded to complete, expandable files of at most 2,000 lines and 512 KiB. Partial reads, large files, binary content, or files that the existing diff loader marks non-expandable stay collapsed and retain their manual controls. A storage error falls back to the current session; malformed or unsupported persisted values fall back to automatic expansion off and a 20-line step.

Changing automatic expansion on while an eligible diff is visible expands it immediately. Turning the preference off affects subsequent diffs and does not silently collapse the file currently being reviewed. The existing explicit collapse action remains available when the current diff owns a restorable expanded state.

Languages and accessibility

The controls and directory accessible names update live in English, playful Hong Kong-style Cantonese, and compact bilingual mode. Flat and Tree are real pressed-state buttons. Directory rows are skipped by keyboard selection, so arrow-key navigation, selected-file state, and assistive names continue to refer to actionable files.

Verification

Focused unit and UI tests cover deterministic nested ordering, unsafe-path fallback, source-index preservation for selection/context menu/double-click, preference persistence and malformed storage, automatic-expansion bounds, and live English/Cantonese/bilingual switching. Existing text-diff expansion tests continue to cover hunk merging, top/bottom expansion, and whole-file expansion.