Function renderRow

src/ui/diff/renderRows.tsx:1348–1731

Render one diff row.

(
  row: DiffRow,
  width: number,
  lineNumberDigits: number,
  showLineNumbers: boolean,
  showHunkHeaders: boolean,
  wrapLines: boolean,
  codeHorizontalOffset: number,
  theme: AppTheme,
  selected: boolean,
  copySelectedRowRange: CopySelectedRowRange | undefined,
  copySelectedSide: "left" | "right" | undefined,
  anchorId?: string,
  noteGuideSide?: "old" | "new",
  showAddNoteBadge = false,
  onHoverRow?: (rowKey: string) => void,
  onStartUserNoteAtHunk?: (hunkIndex: number, target?: UserNoteLineTarget) => void,
  onToggleGap?: (gapKey: string) => void,
)

/** Render one diff row. */
function renderRow(
  row: DiffRow,
  width: number,
  lineNumberDigits: number,
  showLineNumbers: boolean,
  showHunkHeaders: boolean,
  wrapLines: boolean,
  codeHorizontalOffset: number,
  theme: AppTheme,
  selected: boolean,
  copySelectedRowRange: CopySelectedRowRange | undefined,
  copySelectedSide: "left" | "right" | undefined,
  anchorId?: string,
  noteGuideSide?: "old" | "new",
  showAddNoteBadge = false,
  onHoverRow?: (rowKey: string) => void,
  onStartUserNoteAtHunk?: (hunkIndex: number, target?: UserNoteLineTarget) => void,
  onToggleGap?: (gapKey: string) => void,
) {
  const hasCopySelection = !!copySelectedRowRange;
  const reserveAddNoteColumn = Boolean(onStartUserNoteAtHunk);

  // For split rows, the user's drag is anchored to one column-half of the diff. Apply the
  // selection-highlight blend only to that side so it is clear which file (A or B) the
  // selection represents.
  const hasLeftSelection = hasCopySelection && copySelectedSide !== "right";
  const hasRightSelection = hasCopySelection && copySelectedSide !== "left";
  let baseRow: ReactNode;

  if (row.type === "collapsed") {
    baseRow = renderHeaderRow(
      row,
      width,
      theme,
      selected || hasCopySelection,
      anchorId,
      showAddNoteBadge,
      onHoverRow,
      onStartUserNoteAtHunk,
      onToggleGap,
    );
  } else if (row.type === "hunk-header") {
    baseRow = showHunkHeaders
      ? renderHeaderRow(
          row,
          width,
          theme,
          selected || hasCopySelection,
          anchorId,
          showAddNoteBadge,
          onHoverRow,
          onStartUserNoteAtHunk,
        )
      : null;
  } else if (row.type === "split-line") {
    const guideOnOldSide = noteGuideSide === "old";
    const guideOnNewSide = noteGuideSide === "new";
    const addNoteTarget: UserNoteLineTarget | undefined =