Module diff_view 

A diff view over ashlar_diff::FileDiffs: unified or split, virtualized, syntax-coloured per file language, with word-level emphasis, collapsed unchanged ranges, a sticky file header, line selection and hunk navigation.

A frame costs O(visible rows). The row model (files, hunk headers, lines, collapsed ranges) is built once per (revision, mode, expansion) and kept by the view. Lexer states run lazily within each hunk, so jumping to the end of a long diff highlights one hunk, not the whole diff. Row galleys are cached and rebuilt only when the model, the theme or the font changes.

let out = DiffView::new("review.diff", state, files, revision).mode(DiffMode::Split).show(ui);
for line in &out.selected_lines {
    // comment on `line.file`, `line.new_no`…
}

Lines wider than the view scroll sideways (both sides of a split together): the horizontal wheel (Shift+wheel) over the view, or a drag on the thin bar along its bottom.

Input: click selects a row, Shift-click and Shift+arrows extend, ⌘-click toggles. N / F7 moves to the next hunk, P / Shift+F7 to the previous one. Clicking (or Enter on) a collapsed range shows EXPAND_STEP more lines, Alt-click shows all of them. Clicking a file header (or Enter on it) folds the file; clicking the sticky header jumps to its file.

Automation (visible rows only, indices 0-based): <id>.file.<f> (file header), <id>.file.<f>.hunk.<h> (hunk header), <id>.file.<f>.hunk.<h>.line.<k> (line k of the hunk; in split mode the left line, else the right), <id>.file.<f>.gap.<g> (collapsed range), <id>.file.<f>.gap.<g>.line.<n> (expanded line, n its new line number) and <id>.header (the sticky header). AccessKit: the view is a read-only document; file and hunk headers are headings, collapsed ranges buttons, lines paragraphs labelled “added 12: text”.

Structs

DiffLabels

Words the view shows (localized by the app).

DiffResponse

What the view reports this frame.

DiffView

A diff view. See the module docs.

DiffViewState

The view’s state, kept by the app: selection, expanded ranges, folded files.

SelectedLine

One selected line.

Enums

DiffMode

How lines are laid out.

Constants

EXPAND_STEP

Lines one click on a collapsed range reveals.

MAX_SELECTED_LINES

Most entries DiffResponse::selected_lines lists.